:root{font-family:PingFang SC,Microsoft YaHei,system-ui,sans-serif;color:#173f35;background:#f7f4ed;font-synthesis:none;--ink: #163f35;--ink-soft: #547067;--line: rgba(27, 76, 64, .16);--sage: #dce8df;--sage-deep: #789d8f;--gold: #b88a31;--shadow: 0 20px 60px rgba(47, 58, 49, .08)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;min-width:0;min-height:100vh;-webkit-font-smoothing:antialiased;background:#f7f4ed;overflow-x:hidden}button,a{font:inherit}button{color:inherit}a{color:inherit;text-decoration:none}button:focus-visible,a:focus-visible{outline:2px solid #2f7460;outline-offset:4px}.site-shell{width:100%;min-height:100vh;overflow:clip}.site-header{width:min(1320px,calc(100% - 80px));height:108px;margin:0 auto;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;position:relative;z-index:20}.wordmark{display:inline-flex;align-items:center;gap:13px}.wordmark-logo{width:64px;height:64px;flex:0 0 64px;overflow:hidden;border:1px solid rgba(41,82,70,.14);border-radius:18px;background:#f8f8f3;box-shadow:0 7px 20px #18392f17}.wordmark-logo img{display:block;width:100%;height:100%;object-fit:cover;object-position:50% 50%;transform:scale(1.08)}.wordmark-copy{display:inline-flex;flex-direction:column;gap:3px}.wordmark-copy strong{font-family:Songti SC,STSong,serif;font-size:30px;line-height:1;letter-spacing:.1em;font-weight:600}.wordmark-copy>span{font:8px Georgia,serif;line-height:1.2;letter-spacing:.14em;color:var(--ink-soft)}.site-header nav{display:flex;align-items:center;gap:30px;font-size:14px;color:#46665c}.site-header nav a:hover{color:var(--ink)}.nav-apply,.nav-login{border:0;background:none;cursor:pointer;padding:9px 0}.nav-login{border-bottom:1px solid var(--ink);color:var(--ink)!important}.menu-toggle{display:none;background:none;border:0;width:42px;height:42px;cursor:pointer}.menu-toggle span{display:block;width:23px;height:1px;background:var(--ink);margin:7px auto}.login-page{min-height:100dvh;padding:0 24px 56px;background:radial-gradient(circle at 84% 8%,rgba(204,181,122,.13),transparent 26%),var(--paper);color:var(--ink)}.login-page-header{width:min(1110px,100%);margin:0 auto;min-height:92px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between}.login-back{border:0;border-bottom:1px solid var(--ink);padding:8px 0;background:transparent;color:var(--ink);font:inherit;font-size:13px;cursor:pointer}.login-card{width:min(100%,430px);margin:clamp(72px,13vh,150px) auto 0;padding:42px;border:1px solid var(--line);border-radius:18px;background:#fffefac2;box-shadow:0 24px 72px #14372d17}.login-mark{width:52px;height:52px;display:grid;place-items:center;margin-bottom:27px;border:1px solid #d9d1c0;border-radius:50%;color:var(--ink);background:#f6f1e4}.login-card .eyebrow{margin:0 0 13px}.login-card h1{margin:0;font:600 clamp(32px,5vw,42px)/1.18 "Songti SC","STSong",serif;letter-spacing:.04em}.login-intro{margin:14px 0 32px;color:var(--ink-soft);font-size:14px;line-height:1.75}.login-card form{display:grid;gap:17px}.login-card label{display:grid;gap:8px;color:#46665c;font-size:13px}.login-card input{width:100%;height:50px;padding:0 14px;border:1px solid #d5d7cf;border-radius:9px;outline:none;background:#fffc;color:var(--ink);font:inherit;transition:border-color .15s ease,box-shadow .15s ease}.login-card input:focus{border-color:#6d9983;box-shadow:0 0 0 3px #4b80651a}.login-error{margin:-2px 0 0;color:#a14f42;font-size:13px;line-height:1.55}.login-submit{width:100%;min-height:52px;margin-top:7px;justify-content:center}.login-submit:disabled{cursor:wait;opacity:.68}.login-help{margin:27px 0 0;color:#7b867e;font-size:12px;line-height:1.7;text-align:center}.hero{width:min(1320px,calc(100% - 80px));margin:0 auto;padding:112px 0 106px}.eyebrow{margin:0 0 20px;text-transform:uppercase;letter-spacing:.18em;font-size:12px;color:#7c9189}.hero h1{margin:0;max-width:980px;font-family:Songti SC,STSong,serif;font-size:clamp(68px,7.2vw,112px);line-height:1.08;letter-spacing:-.035em;font-weight:500}.hero-rule{width:52px;height:1px;background:var(--gold);margin:46px 0 38px}.hero-copy{max-width:790px;font-size:17px;line-height:2;color:#405e55;margin:0 0 14px}.hero-copy.secondary{color:#687f77}.features-section{padding:84px 0 86px;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}.section-heading{width:min(1320px,calc(100% - 80px));margin:0 auto 40px;display:flex;align-items:flex-end;justify-content:space-between;gap:40px}.section-heading h2{margin:0;font-family:Songti SC,STSong,serif;font-size:clamp(34px,3.5vw,54px);font-weight:500;letter-spacing:-.02em}.rail-controls{display:flex;gap:10px}.rail-controls button{width:44px;height:44px;border:1px solid var(--line);border-radius:50%;background:#ffffff59;cursor:pointer;display:grid;place-items:center;transition:.2s ease}.rail-controls button:hover{background:var(--ink);color:#fff;border-color:var(--ink)}.feature-rail-shell{width:min(1320px,calc(100% - 80px));margin:0 auto;position:relative;overflow:hidden}.feature-rail-edge{position:absolute;z-index:4;top:0;bottom:0;width:72px;pointer-events:none}.feature-rail-edge-left{left:0;background:linear-gradient(90deg,#f7f4ed 8%,#f7f4ed00)}.feature-rail-edge-right{right:0;background:linear-gradient(270deg,#f7f4ed 8%,#f7f4ed00)}.feature-track{width:100%;display:flex;gap:20px;overflow-x:auto;scroll-snap-type:x mandatory;scrollbar-width:none;padding:22px 44px 38px;cursor:default;touch-action:auto;-webkit-user-select:none;user-select:none}.feature-track.pointer-scrolling{scroll-snap-type:none}.feature-track::-webkit-scrollbar{display:none}.feature-card{flex:0 0 clamp(260px,22vw,292px);min-height:468px;padding:0;border:1px solid rgba(30,72,61,.16);border-radius:18px;overflow:hidden;text-align:left;background:#fbf9f4;scroll-snap-align:center;cursor:pointer;transition:transform .34s ease,box-shadow .34s ease,border-color .34s ease,background .34s ease}.feature-card:hover,.feature-card.active{transform:translateY(-8px);box-shadow:0 24px 64px #22342d1c;border-color:#163f3557;background:#fffdf8}.feature-card.preview-only{cursor:default}.feature-card.preview-only:hover:not(.active){transform:none;box-shadow:none;border-color:#1e483d29;background:#fbf9f4}.feature-card.preview-only:hover:not(.active) .card-visual img{transform:scale(1.01);filter:saturate(.96) contrast(1.02)}.card-visual{height:306px;overflow:hidden;border-bottom:1px solid var(--line);background:#eeeade;position:relative}.card-visual img{display:block;width:100%;height:100%;object-fit:cover;transform:scale(1.01);filter:saturate(.96) contrast(1.02);transition:transform .75s cubic-bezier(.2,.7,.2,1),filter .4s ease}.feature-card:hover .card-visual img,.feature-card.active .card-visual img{transform:scale(1.055);filter:saturate(1.04) contrast(1.04)}.card-play{position:absolute;left:18px;bottom:18px;min-height:34px;padding:0 13px;border-radius:999px;display:inline-flex;align-items:center;gap:7px;background:#13372edb;color:#fff;font-size:11px;letter-spacing:.03em;opacity:0;transform:translateY(7px);transition:opacity .28s ease,transform .28s ease;-webkit-backdrop-filter:blur(9px);backdrop-filter:blur(9px)}.feature-card:hover .card-play,.feature-card:focus-visible .card-play,.feature-card.active .card-play{opacity:1;transform:translateY(0)}.card-copy{padding:19px 20px 23px}.card-title-row{min-height:43px;display:grid;grid-template-columns:auto minmax(0,1fr) auto;align-items:center;gap:12px}.card-number{font:500 36px/1 Georgia,Times New Roman,serif;letter-spacing:-.04em;color:#2e5d50}.card-icon{color:#789087;display:grid;place-items:center}.card-copy h3{min-width:0;font-family:Songti SC,STSong,serif;font-size:23px;line-height:1.15;font-weight:600;margin:0;white-space:nowrap}.card-copy p{margin:10px 0 0;color:#6b8179;font-size:13px;line-height:1.55;display:-webkit-box;-webkit-box-orient:vertical;-webkit-line-clamp:2;overflow:hidden}.demo{width:100%;color:var(--ink);position:relative}.demo-status{display:flex;align-items:center;justify-content:space-between;gap:18px;margin:-8px 0 24px;color:#899991;font-size:10px;letter-spacing:.1em}.demo-status>i{display:block;flex:1;height:1px;background:#163f351f;overflow:hidden;position:relative}.demo-status>i:after{content:"";position:absolute;inset:0 auto 0 0;width:38%;background:var(--gold);animation:demo-progress 7.2s linear infinite}.demo-split,.similar-demo{display:flex;align-items:center;justify-content:center;gap:12px}.paper-fragment{width:92px;height:110px;border:1px solid rgba(22,63,53,.18);background:#ffffffb8;padding:18px 10px;position:relative;display:flex;align-items:center;justify-content:center;font:12px Georgia,serif}.paper-fragment b{color:#b65a49;position:absolute;right:8px;bottom:8px}.paper-fragment.clean{border-color:#8bb3a1}.paper-fragment.clean svg{position:absolute;right:8px;bottom:8px;color:#4f8b72}.review-demo{display:grid;gap:18px}.review-line{display:grid;gap:7px;font-size:12px;color:#647b73}.review-line i{height:5px;display:block;border-radius:10px;background:var(--sage-deep);transform-origin:left;animation:line-grow 7.2s ease-in-out infinite}.review-line:nth-child(2) i{animation-delay:.45s}.review-line:nth-child(3) i{animation-delay:.9s}.precision-search-demo{display:grid;gap:9px}.precision-problem{border:1px solid rgba(22,63,53,.13);border-radius:12px;background:#ffffffad;padding:12px 14px;overflow:hidden}.precision-problem-head{display:flex;align-items:center;justify-content:space-between;gap:14px;margin-bottom:7px}.precision-problem-head span{font-size:10px;letter-spacing:.08em;font-weight:700;color:#58746a}.precision-problem-head small{font-size:9px;color:#8a9b94}.precision-problem p{margin:0;color:#526b62;font:11px/1.8 PingFang SC,Microsoft YaHei,sans-serif}.precision-problem mark{border-radius:3px;padding:0 2px;color:inherit;background:transparent}.source-hit{animation:source-term-highlight 9.6s ease-in-out infinite}.source-hit-2{animation-name:source-term-highlight-2}.source-hit-3{animation-name:source-term-highlight-3}.source-hit-4{animation-name:source-term-highlight-4}.source-hit-5{animation-name:source-term-highlight-5}.precision-query{min-height:41px;border:1px solid rgba(22,63,53,.22);border-radius:11px;background:#f8faf7eb;padding:7px 9px;display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:7px;overflow:hidden}.precision-query>svg{color:#628176}.precision-query-tags{display:flex;align-items:center;gap:4px;min-width:0;overflow:hidden}.query-tag{flex:0 0 auto;border-radius:999px;border:1px solid #d5b96e;background:#fbf4df;color:#8b681f;padding:4px 6px;font-size:9px;line-height:1;opacity:0;transform:translateY(6px) scale(.94);animation:query-tag-one 9.6s ease-in-out infinite}.query-tag-2{animation-name:query-tag-two}.query-tag-3{animation-name:query-tag-three}.query-tag-4{animation-name:query-tag-four}.query-tag-5{animation-name:query-tag-five}.precision-query b{border-left:1px solid rgba(22,63,53,.14);padding-left:7px;color:#789087;font-size:8px;letter-spacing:.08em}.precision-match-note{display:flex;align-items:center;justify-content:center;gap:5px;height:17px;color:#3f7866;font-size:9px;opacity:0;animation:precision-match-note 9.6s ease-in-out infinite}.precision-result{border-color:#3777653b;opacity:0;transform:translateY(8px);animation:precision-result-in 9.6s ease-in-out infinite}.precision-result .precision-problem-head span{color:#2e735f}.result-hit{animation:result-term-highlight 9.6s ease-in-out infinite}.mini-question{width:66px;height:94px;border:1px solid var(--line);background:#ffffffad;display:grid;place-items:center;font-size:12px;transition:.25s ease}.mini-question.active{height:126px;border-color:#648e7e;box-shadow:0 14px 34px #2d4d411f;animation:source-question 7.2s ease-in-out infinite}.mini-question.faded{opacity:.55}.paper-composer-demo{min-height:250px;position:relative;overflow:hidden}.paper-scene{position:absolute;top:0;right:0;bottom:0;left:0;border:1px solid rgba(22,63,53,.14);border-radius:12px;background:#ffffffb8;padding:13px;opacity:0;transform:translate(18px)}.paper-scene-head{display:flex;justify-content:space-between;align-items:center;gap:12px;padding-bottom:8px;border-bottom:1px solid rgba(22,63,53,.1)}.paper-scene-head span{font-size:10px;font-weight:700;letter-spacing:.06em}.paper-scene-head small{color:#82938c;font-size:9px}.paper-pick-scene{animation:paper-pick-scene 10.8s ease-in-out infinite}.paper-question-list{display:grid;gap:6px;padding-top:8px}.paper-question-row{height:38px;display:grid;grid-template-columns:18px 1fr auto;align-items:center;gap:7px;padding:0 9px;border:1px solid rgba(22,63,53,.1);border-radius:8px;color:#657b73;font-size:9px;background:#fbfaf6}.paper-question-row i{width:15px;height:15px;border:1px solid #9fb2aa;border-radius:4px;display:grid;place-items:center;color:#fff;background:transparent}.paper-question-row i svg{opacity:0}.paper-question-row b{color:#9aa8a3;font-size:8px}.paper-question-1 i{animation:paper-check-one 10.8s ease-in-out infinite}.paper-question-1 i svg{animation:paper-check-icon-one 10.8s ease-in-out infinite}.paper-question-2 i{animation:paper-check-two 10.8s ease-in-out infinite}.paper-question-2 i svg{animation:paper-check-icon-two 10.8s ease-in-out infinite}.paper-question-3 i{animation:paper-check-three 10.8s ease-in-out infinite}.paper-question-3 i svg{animation:paper-check-icon-three 10.8s ease-in-out infinite}.paper-pick-action{display:flex;align-items:center;justify-content:space-between;margin-top:8px;font-size:9px;color:#72877f}.paper-pick-action button{border:0;border-radius:7px;background:var(--ink);color:#fff;padding:6px 9px;display:inline-flex;align-items:center;gap:5px;font-size:9px;transform:scale(.96);animation:paper-action-press 10.8s ease-in-out infinite}.paper-layout-scene{animation:paper-layout-scene 10.8s ease-in-out infinite}.paper-layout-body{display:grid;grid-template-columns:118px 1fr;gap:10px;padding-top:9px;height:198px}.paper-controls{display:grid;align-content:start;gap:6px}.paper-control{height:37px;border:1px solid rgba(22,63,53,.12);border-radius:8px;padding:0 7px;display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:5px;color:#73877f;background:#f9f8f3;font-size:8px}.paper-control b{color:#315f51;font-size:8px}.paper-control-font{animation:paper-control-font 10.8s ease-in-out infinite}.paper-control-gap{animation:paper-control-gap 10.8s ease-in-out infinite}.paper-control-space{animation:paper-control-space 10.8s ease-in-out infinite}.paper-layout-sheet{background:#fffefb;border:1px solid #cbd5d1;box-shadow:0 8px 20px #2a3d3412;padding:11px 12px;overflow:hidden}.paper-layout-sheet>strong{display:block;text-align:center;font:600 11px Songti SC,serif}.paper-layout-sheet>small{display:block;text-align:center;color:#9aa7a2;font-size:6px;margin:3px 0 8px}.paper-layout-sheet p{margin:0 0 9px;padding-bottom:5px;border-bottom:1px dashed #dce2df;color:#6c7c76;font-size:7px;line-height:1.45;animation:paper-question-spacing 10.8s ease-in-out infinite}.paper-print-scene{display:grid;grid-template-rows:auto 1fr auto;gap:8px;animation:paper-print-scene 10.8s ease-in-out infinite}.paper-print-label{display:flex;align-items:center;gap:6px;color:#326856;font-size:10px;font-weight:700}.paper-print-label small{margin-left:auto;font-size:8px;font-weight:400;color:#8a9993}.paper-print-sheet{width:78%;justify-self:center;background:#fff;border:1px solid #c7d1cd;box-shadow:0 12px 30px #273b321a;padding:14px 16px;transform:scale(.94);animation:paper-preview-settle 10.8s ease-in-out infinite}.paper-print-sheet header{text-align:center;border-bottom:1px solid #d9dfdc;padding-bottom:7px;margin-bottom:8px}.paper-print-sheet header strong{display:block;font:600 12px Songti SC,serif}.paper-print-sheet header small{color:#929f9a;font-size:6px}.paper-print-sheet p{margin:0 0 8px;color:#556b63;font-size:7px;line-height:1.55}.paper-print-ready{justify-self:center;display:flex;align-items:center;gap:5px;color:#3f7865;font-size:9px;opacity:0;animation:paper-ready-in 10.8s ease-in-out infinite}.demo-paper .demo-status>i:after{animation-duration:10.8s}.geometry-demo{display:flex;align-items:center;justify-content:center;gap:22px}.geometry-demo>div{display:grid;gap:9px;font-size:11px;color:#60786f}.geometry-demo>svg{animation:geometry-turn 7.2s ease-in-out infinite}.geometry-demo span{border-bottom:1px solid #b8c7c1;padding-bottom:6px;animation:method-step 7.2s ease-in-out infinite}.geometry-demo span:nth-child(2){animation-delay:.4s}.geometry-demo span:nth-child(3){animation-delay:.8s}.challenge-demo{display:grid;grid-template-columns:repeat(3,45px);justify-content:center;gap:8px}.challenge-demo span{height:45px;border:1px solid var(--line);display:grid;place-items:center;background:#ffffff80}.challenge-demo span.picked{border-color:#d4ab55;color:#9d721d;background:#f4ead1;animation:challenge-pick 7.2s ease-in-out infinite}.challenge-demo span:nth-child(5){animation-delay:.35s}.challenge-demo span:nth-child(6){animation-delay:.7s}.challenge-demo p{grid-column:1 / -1;text-align:center;margin:7px 0 0;font-size:11px;color:#6b8179}.poetry-demo{text-align:center;font-family:Songti SC,serif;font-size:17px;line-height:1.8}.poetry-modes{display:flex;justify-content:center;gap:5px;margin-bottom:12px;font:10px PingFang SC,sans-serif;color:#778b83}.poetry-modes span{border:1px solid var(--line);border-radius:20px;padding:3px 7px;animation:mode-cycle 7.2s ease-in-out infinite}.poetry-modes span:nth-child(2){animation-delay:1.9s}.poetry-modes span:nth-child(3){animation-delay:3.8s}.poetry-demo p{margin:3px 0}.poetry-demo .blank{letter-spacing:.25em;color:#a7b4af;animation:poetry-hide 7.2s ease-in-out infinite}.poetry-demo .writing{color:var(--gold);font-style:italic;clip-path:inset(0 100% 0 0);animation:handwriting-reveal 7.2s ease-in-out infinite}.article-import-demo{min-height:254px;position:relative;overflow:hidden}.article-scene{position:absolute;top:0;right:0;bottom:0;left:0;border:1px solid rgba(22,63,53,.14);border-radius:12px;background:#ffffffbd;overflow:hidden;opacity:0;transform:translate(18px)}.article-source-scene{animation:article-source-scene 11.2s ease-in-out infinite}.article-browser-bar{height:30px;display:flex;align-items:center;gap:5px;padding:0 10px;background:#f1f2ee;border-bottom:1px solid rgba(22,63,53,.09)}.article-browser-bar>i{width:5px;height:5px;border-radius:50%;background:#b9c3bf}.article-browser-bar span{margin-left:5px;min-width:0;flex:1;border-radius:6px;background:#ffffffb8;color:#788a83;padding:4px 7px;display:flex;align-items:center;gap:4px;font-size:8px}.article-source-body{padding:18px 20px 12px}.article-source-body small{display:block;color:#a3443c;font-size:7px;font-weight:700;letter-spacing:.1em;margin-bottom:8px}.article-source-body strong{display:block;max-width:360px;color:#203f36;font:600 16px/1.25 Georgia,Times New Roman,serif}.article-source-body p{max-width:370px;margin:11px 0 0;padding:4px 5px;color:#526a62;font:10px/1.7 Georgia,Times New Roman,serif;background:linear-gradient(90deg,#d9e9e2 0,#d9e9e2 0) no-repeat;background-size:0 100%;animation:article-text-select 11.2s ease-in-out infinite}.article-copy-tip{position:absolute;right:15px;bottom:13px;display:flex;align-items:center;gap:5px;border:1px solid #9eb8ad;border-radius:999px;background:#f8fbf8;color:#426d5e;padding:5px 8px;font-size:8px;opacity:0;transform:translateY(4px);animation:article-copy-tip 11.2s ease-in-out infinite}.article-paste-scene{padding:14px;animation:article-paste-scene 11.2s ease-in-out infinite}.article-scene-title{display:flex;align-items:center;justify-content:space-between;gap:10px;padding-bottom:9px;border-bottom:1px solid rgba(22,63,53,.1)}.article-scene-title>span{display:flex;align-items:center;gap:5px;font-size:10px;font-weight:700}.article-scene-title>small{color:#879790;font-size:8px}.article-paste-box{height:128px;margin-top:11px;border:1px solid rgba(22,63,53,.17);border-radius:9px;background:#fbfaf6;padding:12px;color:#536b62;font:10px/1.8 Georgia,Times New Roman,serif;overflow:hidden}.article-paste-box span{display:inline;opacity:0;animation:article-paste-text 11.2s ease-in-out infinite}.article-paste-box i{display:inline-block;width:1px;height:11px;margin-left:2px;vertical-align:-1px;background:#3f6f5f;animation:article-paste-caret 11.2s steps(1) infinite}.article-generate-row{display:flex;align-items:center;justify-content:space-between;margin-top:10px}.article-generate-row small{color:#80928a;font-size:8px}.article-generate-row button{border:0;border-radius:7px;background:var(--ink);color:#fff;padding:7px 10px;display:inline-flex;align-items:center;gap:5px;font-size:8px;animation:article-generate-press 11.2s ease-in-out infinite}.article-result-scene{padding:14px;animation:article-result-scene 11.2s ease-in-out infinite}.article-result-body{display:grid;grid-template-columns:1.2fr .9fr;gap:10px;padding-top:11px;height:198px}.article-bilingual-card{border:1px solid rgba(22,63,53,.13);border-radius:9px;background:#fbfaf6;padding:13px;position:relative}.article-bilingual-card button{width:27px;height:27px;border:1px solid #99b4a8;border-radius:50%;background:#e7f0eb;color:#3a745f;display:grid;place-items:center;margin-bottom:9px}.article-bilingual-card p{margin:0;color:#294f42;font:10px/1.65 Georgia,Times New Roman,serif}.article-bilingual-card small{display:block;color:#788b83;font-size:8px;line-height:1.6;margin-top:8px}.article-output-grid{display:grid;grid-template-columns:1fr 1fr;gap:6px}.article-output-grid>span{border:1px solid rgba(22,63,53,.12);border-radius:8px;background:#f8f7f2;padding:8px 6px;color:#668078;display:grid;align-content:center;justify-items:start;gap:3px;opacity:0;transform:translateY(5px)}.article-output-grid b{color:#315f51;font-size:8px}.article-output-grid small{color:#8c9a95;font-size:7px}.article-output-1{animation:article-output-one 11.2s ease-in-out infinite}.article-output-2{animation:article-output-two 11.2s ease-in-out infinite}.article-output-3{animation:article-output-three 11.2s ease-in-out infinite}.article-output-4{animation:article-output-four 11.2s ease-in-out infinite}.demo-reading .demo-status>i:after{animation-duration:11.2s}.vocab-demo{display:grid;grid-template-columns:1fr 1fr;gap:8px}.vocab-demo span{border:1px solid var(--line);background:#ffffff80;padding:12px 6px;text-align:center;font-size:10px;line-height:1.7;animation:vocab-mode 7.2s ease-in-out infinite}.vocab-demo span:nth-child(2){animation-delay:1.2s}.vocab-demo span:nth-child(3){animation-delay:2.4s}.vocab-demo span:nth-child(4){animation-delay:3.6s}.vocab-demo b{font:17px Georgia,serif;letter-spacing:.08em}.movie-learning-demo{min-height:262px;position:relative;overflow:hidden}.movie-scene{position:absolute;top:0;right:0;bottom:0;left:0;border:1px solid rgba(22,63,53,.14);border-radius:12px;background:#ffffffbd;padding:12px;opacity:0;transform:translate(18px)}.movie-watch-scene{display:grid;grid-template-rows:154px auto auto;gap:7px;animation:movie-watch-scene 10.8s ease-in-out infinite}.movie-player-mini{position:relative;border-radius:9px;overflow:hidden;background:#24352f}.movie-player-mini>img{width:100%;height:100%;object-fit:cover;filter:brightness(.66) saturate(.72);transform:scale(1.03)}.movie-subtitle-switch{position:absolute;right:8px;top:8px;display:flex;gap:3px;padding:3px;border-radius:999px;background:#0f221ca8;-webkit-backdrop-filter:blur(5px);backdrop-filter:blur(5px)}.movie-subtitle-switch span{min-width:25px;border-radius:999px;padding:4px 5px;color:#ffffffad;text-align:center;font-size:7px}.movie-subtitle-en{animation:movie-en-toggle 10.8s ease-in-out infinite}.movie-subtitle-cn{animation:movie-cn-toggle 10.8s ease-in-out infinite}.movie-subtitle-lines{position:absolute;inset:auto 12px 12px;text-align:center;color:#f2f1e9;text-shadow:0 1px 3px rgba(0,0,0,.6)}.movie-subtitle-lines p{margin:0;font:11px/1.5 Georgia,Times New Roman,serif;animation:movie-english-subtitle 10.8s ease-in-out infinite}.movie-subtitle-lines small{display:block;margin-top:2px;font-size:8px;color:#e3e4de;animation:movie-chinese-subtitle 10.8s ease-in-out infinite}.movie-subtitle-lines mark{border-radius:3px;background:#e6cf83;color:#3b331e;padding:0 2px;animation:movie-word-highlight 10.8s ease-in-out infinite}.movie-word-action,.movie-learning-tip{min-height:34px;border:1px solid rgba(22,63,53,.12);border-radius:8px;background:#faf9f4;display:flex;align-items:center;gap:6px;padding:6px 8px;font-size:8px;color:#6d8179}.movie-word-action{opacity:0;transform:translateY(4px);animation:movie-word-action 10.8s ease-in-out infinite}.movie-word-action span{flex:1}.movie-word-action b{color:#315f51;font:600 9px Georgia,serif}.movie-word-action button{border:0;border-radius:6px;background:#e5eee9;color:#3b735f;padding:5px 7px;font-size:7px;animation:movie-word-add 10.8s ease-in-out infinite}.movie-learning-tip{opacity:0;transform:translateY(4px);animation:movie-tip-show 10.8s ease-in-out infinite}.movie-learning-tip svg{color:#af822a}.movie-learning-tip b{color:#8d681f;margin-right:5px}.movie-practice-scene{animation:movie-practice-scene 10.8s ease-in-out infinite}.movie-practice-head{display:flex;justify-content:space-between;align-items:center;padding-bottom:9px;border-bottom:1px solid rgba(22,63,53,.1)}.movie-practice-head span{display:flex;align-items:center;gap:5px;color:#315f51;font-size:10px;font-weight:700}.movie-practice-head small{color:#8a9993;font-size:7px}.movie-practice-input{height:70px;margin-top:13px;border:1px solid rgba(22,63,53,.17);border-radius:9px;background:#fbfaf6;display:flex;align-items:center;padding:0 13px;overflow:hidden;color:#315f51;font:11px Georgia,Times New Roman,serif}.movie-line-typing{width:0;overflow:hidden;white-space:nowrap;animation:movie-line-type 10.8s steps(34,end) infinite}.movie-practice-input>i{width:1px;height:13px;background:#386b59;animation:movie-input-caret 10.8s steps(1) infinite}.movie-practice-translation{margin:7px 0 9px;text-align:center;color:#7a8d85;font-size:8px}.movie-completion-line{border:1px solid #d6b45f;border-radius:8px;background:#fbf4df;padding:8px 10px;color:#8e681c;opacity:0;transform:translateY(5px);animation:movie-completion-show 10.8s ease-in-out infinite}.movie-completion-line>div{display:flex;align-items:center;gap:4px;margin-bottom:4px;font-size:7px;font-weight:700}.movie-completion-line p{margin:0;font:9px Georgia,Times New Roman,serif}.movie-completion-line small{display:block;margin-top:3px;color:#a28345;font-size:7px}.demo-movie .demo-status>i:after{animation-duration:10.8s}.physics-demo{width:100%}.demo-physics .demo-status>i:after{animation-duration:9.6s}.lab-stage{position:relative;width:100%;aspect-ratio:560 / 260;overflow:hidden;border:1px solid rgba(36,89,72,.13);border-radius:13px;background:radial-gradient(circle at 1px 1px,rgba(62,117,96,.15) 1px,transparent 1.25px) 0 0 / 18px 18px,linear-gradient(150deg,#ebf5eff0,#f6f3e9f0);box-shadow:inset 0 1px #ffffffb8}.lab-wires{position:absolute;top:0;right:0;bottom:0;left:0;z-index:1;width:100%;height:100%;overflow:visible}.lab-wire{fill:none;stroke:#364e49;stroke-width:3.2;stroke-linecap:round;stroke-linejoin:round;stroke-dasharray:640;stroke-dashoffset:640;filter:drop-shadow(0 2px 1px rgba(22,50,41,.12));animation:lab-wire-build 9.6s cubic-bezier(.25,.72,.28,1) infinite}.lab-wire-3,.lab-wire-4,.lab-wire-6,.lab-wire-7{animation-name:lab-wire-build-late}.lab-apparatus,.lab-meter{position:absolute;z-index:3;opacity:0;transform:translateY(9px) scale(.86)}.lab-apparatus img,.lab-meter img{display:block;width:100%;height:100%;object-fit:contain}.lab-battery{left:5.5%;top:57%;width:17%;height:31%;animation:lab-part-early 9.6s ease infinite}.lab-switch{left:23%;top:28%;width:15%;height:26%;animation:lab-part-second 9.6s ease infinite}.lab-switch img{position:absolute;top:0;right:0;bottom:0;left:0}.lab-switch .switch-open{animation:lab-switch-open 9.6s step-end infinite}.lab-switch .switch-closed{animation:lab-switch-closed 9.6s step-end infinite}.lab-rheostat{left:42.5%;top:14%;width:27%;height:31%;animation:lab-part-third 9.6s ease infinite}.lab-rheostat-slider{position:absolute;z-index:4;left:80%;top:18%;width:9px;height:24px;border:1px solid rgba(17,24,28,.8);border-radius:4px;background:linear-gradient(145deg,#555f64,#20282b);box-shadow:0 3px 6px #1f2d363d;transform:translate(-50%);animation:lab-rheostat-adjust 9.6s ease-in-out infinite}.lab-lamp{left:75%;top:60%;width:17%;height:30%;animation:lab-part-fourth 9.6s ease infinite}.lab-lamp img{position:relative;z-index:2;filter:brightness(1) saturate(1);animation:lab-lamp-image 9.6s ease-in-out infinite}.lab-lamp-glow{position:absolute;z-index:1;left:50%;top:36%;width:58%;aspect-ratio:1;border-radius:50%;background:radial-gradient(circle,rgba(255,250,196,.98) 0 18%,rgba(255,205,55,.78) 34%,transparent 72%);filter:blur(7px);opacity:0;transform:translate(-50%,-50%) scale(.72);animation:lab-lamp-brightness 9.6s ease-in-out infinite}.lab-meter{width:14%;aspect-ratio:1;transform-origin:50% 50%;animation:lab-meter-enter 9.6s ease infinite}.lab-meter-a{left:76.5%;top:16%}.lab-meter-v{left:56%;top:57%}.lab-meter-face{position:relative;width:100%;height:100%}.lab-meter-face img{position:absolute;top:0;right:0;bottom:0;left:0}.lab-meter-needle{position:absolute;z-index:2;left:50%;top:49%;width:24%;height:1.3px;border-radius:99px;background:linear-gradient(90deg,#c8322b,#e75e4a 82%,#222d34 82%);box-shadow:0 1px 2px #1f242847;transform-origin:0 50%}.lab-meter-a .lab-meter-needle{animation:lab-ammeter-needle 9.6s ease-in-out infinite}.lab-meter-v .lab-meter-needle{animation:lab-voltmeter-needle 9.6s ease-in-out infinite}.lab-meter-pivot{position:absolute;z-index:3;left:50%;top:49%;width:7px;height:7px;border:1px solid #2b3032;border-radius:50%;background:radial-gradient(circle at 38% 34%,#fff 0,#fff 16%,#b8b7b2 17%,#b8b7b2 56%,#34383a 57%);transform:translate(-50%,-50%)}.lab-meter-readings{position:absolute;left:50%;bottom:-5px;width:72px;height:25px;overflow:hidden;border:1px solid rgba(30,75,62,.2);border-radius:7px;background:#fdfbf5f0;box-shadow:0 8px 22px #20433824;color:#244f43;font:700 10px/23px ui-monospace,SFMono-Regular,Consolas,monospace;text-align:center;opacity:0;transform:translate(-50%,4px);animation:lab-reading-pop 9.6s ease infinite}.lab-meter-readings span{position:absolute;top:0;right:0;bottom:0;left:0;opacity:0}.reading-step-1{animation:lab-reading-one 9.6s step-end infinite}.reading-step-2{animation:lab-reading-two 9.6s step-end infinite}.reading-step-3{animation:lab-reading-three 9.6s step-end infinite}.lab-caption{position:absolute;z-index:5;left:16px;bottom:13px;height:24px;min-width:132px;color:#56756a;font-size:10px;letter-spacing:.08em}.lab-caption span{position:absolute;inset:0 auto auto 0;white-space:nowrap;opacity:0}.lab-caption-build{animation:lab-caption-build 9.6s ease infinite}.lab-caption-switch{animation:lab-caption-switch 9.6s ease infinite}.lab-caption-adjust{animation:lab-caption-adjust 9.6s ease infinite}.heatmap-demo>div{display:grid;grid-template-columns:repeat(7,13px);justify-content:center;gap:5px}.heatmap-demo i{width:13px;height:13px;background:#e8ece8;border-radius:2px;animation:heat-cell 7.2s ease-in-out infinite;animation-delay:calc(var(--cell) * 55ms)}.heatmap-demo .level-1{--heat-color: #d7e4dc}.heatmap-demo .level-2{--heat-color: #afc9bc}.heatmap-demo .level-3{--heat-color: #739f8b}.heatmap-demo .level-4{--heat-color: #2f715a}.heatmap-demo .level-0{--heat-color: #e8ece8}.heatmap-demo p{text-align:center;font-size:11px;color:#6d827a;margin:15px 0 0}.wrong-import-demo{min-height:220px;display:grid;grid-template-columns:1fr auto 1fr auto 1fr;align-items:center;gap:9px}.wrong-import-step{min-width:0;height:176px;border:1px solid rgba(22,63,53,.14);border-radius:12px;background:#ffffffb8;padding:11px;overflow:hidden}.wrong-import-step>small{display:block;color:#789087;font-size:8px;letter-spacing:.07em;margin-bottom:12px}.wrong-import-paper{height:118px;background:#fbfaf5;border:1px solid rgba(22,63,53,.13);padding:17px 12px;position:relative;font:10px/1.8 Georgia,Songti SC,serif;overflow:hidden}.wrong-import-paper p{margin:0}.wrong-import-paper b{display:block;color:#b45e50;font-weight:500;transform:rotate(-4deg);margin-top:13px}.wrong-import-paper>i{position:absolute;right:11px;bottom:8px;color:#b45e50;font:700 20px/1 sans-serif}.eraser-pass{position:absolute;left:-28px;top:58px;width:40px;height:18px;border-radius:4px;background:#e7ded0;box-shadow:0 3px 7px #2c373024;animation:eraser-sweep 8.4s ease-in-out infinite}.wrong-import-pair>div{display:grid;gap:7px}.wrong-import-pair>div span{padding:11px 7px;border:1px solid var(--line);background:#f9f7f1;text-align:center;font-size:9px}.wrong-import-pair em{margin-top:10px;color:#3f7865;font-size:8px;font-style:normal;display:flex;align-items:center;justify-content:center;gap:4px;opacity:0;animation:import-complete 8.4s ease-in-out infinite}.demo-wrongImport .demo-status>i:after{animation-duration:8.4s}.wrong-review-workspace{min-height:230px;display:grid;grid-template-columns:.86fr 1.14fr;grid-template-rows:1fr auto;gap:10px}.review-question-pane,.review-writing-pane{min-width:0;border:1px solid rgba(22,63,53,.14);border-radius:12px;background:#ffffffb3;padding:14px}.review-question-pane small,.review-writing-pane small{color:#789087;font-size:8px}.review-question-pane p{margin:18px 0 13px;font:11px/1.9 Songti SC,serif}.review-question-pane span{font-size:8px;color:#98a49f}.review-writing-pane{position:relative;background-image:linear-gradient(rgba(43,91,76,.05) 1px,transparent 1px),linear-gradient(90deg,rgba(43,91,76,.05) 1px,transparent 1px);background-size:18px 18px;overflow:hidden}.review-writing-pane b{position:absolute;right:9px;bottom:8px;color:#8c9b95;font-size:8px;font-weight:500}.writing-stroke{position:absolute;left:25px;height:2px;border-radius:99px;background:#315b50;transform-origin:left;animation:write-answer 8.8s ease-in-out infinite}.stroke-one{top:75px;width:82px;transform:rotate(-7deg)}.stroke-two{top:105px;width:112px;transform:rotate(5deg);animation-delay:.55s}.stroke-three{top:135px;width:70px;transform:rotate(-3deg);animation-delay:1.1s}.review-help-row{grid-column:1 / -1;display:grid;grid-template-columns:repeat(3,1fr) 1.4fr;gap:5px}.review-help-row span,.review-help-row strong{min-height:30px;border:1px solid var(--line);border-radius:7px;display:flex;align-items:center;justify-content:center;font-size:8px;font-weight:500;background:#ffffffa3}.review-help-row strong{color:#976f1e;border-color:#d7b666;background:#f7edcf;gap:4px;animation:review-next 8.8s ease-in-out infinite}.similar-question-demo{min-height:232px;display:grid;grid-template-rows:auto 24px 1fr}.similar-source-card{justify-self:center;width:min(310px,88%);border:1px solid rgba(22,63,53,.18);border-radius:10px;background:#fffdf8;padding:12px 15px;text-align:center;box-shadow:0 8px 22px #24362f0d}.similar-source-card small{color:#7f938b;font-size:8px}.similar-source-card p{margin:5px 0;font:12px Songti SC,serif}.similar-source-card b{font-size:8px;color:#9a7526}.similar-link-line{display:flex;align-items:center;justify-content:center;gap:8px;color:#81938c;font-size:8px}.similar-link-line i{width:58px;height:1px;background:var(--line);transform-origin:center;animation:similar-link-grow 8.6s ease-in-out infinite}.similar-results-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:7px}.similar-results-grid article{border:1px solid rgba(22,63,53,.13);border-radius:10px;background:#ffffffa3;padding:10px;opacity:.28;transform:translateY(7px);animation:similar-card-in 8.6s ease-in-out infinite}.similar-results-grid article:nth-child(2){animation-delay:.45s}.similar-results-grid article:nth-child(3){animation-delay:.9s}.similar-results-grid small{color:#728980;font-size:7px}.similar-results-grid p{min-height:34px;margin:7px 0 8px;font:9px/1.6 Songti SC,serif}.similar-results-grid b{color:#9a7526;font-size:7px}.geometry-model-demo{min-height:236px;display:grid;grid-template-columns:1fr 1.08fr;gap:12px}.geometry-model-visual{position:relative;border:1px solid rgba(22,63,53,.14);border-radius:12px;background:#f3f0e7;overflow:hidden}.geometry-model-visual img{width:100%;height:100%;object-fit:cover;filter:saturate(.86) contrast(.98)}.geometry-model-visual span{position:absolute;left:9px;bottom:9px;border-radius:999px;background:#14342bd1;color:#fff;padding:5px 9px;font-size:8px}.geometry-model-steps{display:grid;gap:7px}.geometry-model-steps>div{border:1px solid var(--line);border-radius:10px;background:#ffffffa8;padding:11px 12px;opacity:.42;animation:geometry-step-in 8.4s ease-in-out infinite}.geometry-model-steps>div:nth-child(2){animation-delay:.65s}.geometry-model-steps>div:nth-child(3){animation-delay:1.3s}.geometry-model-steps b{display:block;margin-bottom:5px;font-size:9px}.geometry-model-steps small{color:#71877f;font-size:7px;line-height:1.5}.challenge-question-demo{min-height:232px;display:grid;grid-template-columns:1.5fr .8fr;gap:11px}.challenge-paper{border:1px solid rgba(22,63,53,.14);border-radius:11px;background:#ffffffb8;padding:13px}.challenge-paper header{font:11px Songti SC,serif;text-align:center;border-bottom:1px solid var(--line);padding-bottom:9px;margin-bottom:11px}.challenge-section{display:grid;grid-template-columns:52px repeat(8,1fr);gap:4px;align-items:center;margin-bottom:8px}.challenge-section span{font-size:8px;color:#71877f}.challenge-section i{height:22px;border:1px solid var(--line);display:grid;place-items:center;font-size:7px;font-style:normal}.challenge-section i.selected{color:#8e681c;border-color:#d4a94e;background:#f5e7bd;animation:challenge-extract 8.2s ease-in-out infinite}.challenge-summary{border:1px solid #d4b46b;border-radius:11px;background:#f8eed3;color:#7f601d;padding:16px 10px;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;opacity:.35;animation:challenge-summary-in 8.2s ease-in-out infinite}.challenge-summary b{margin:10px 0 8px;font:12px Songti SC,serif}.challenge-summary span{font-size:7px;line-height:1.7}.poetry-writing-demo{min-height:240px;display:grid;grid-template-rows:auto 1fr auto;gap:10px}.poetry-mode-tabs,.vocab-mode-tabs{display:grid;grid-template-columns:repeat(4,1fr);gap:5px}.poetry-mode-tabs span,.vocab-mode-tabs span{border:1px solid var(--line);border-radius:999px;padding:5px 4px;text-align:center;color:#758a82;font-size:7px;animation:mode-cycle 8.4s ease-in-out infinite}.poetry-mode-tabs span:nth-child(2),.vocab-mode-tabs span:nth-child(2){animation-delay:1.4s}.poetry-mode-tabs span:nth-child(3),.vocab-mode-tabs span:nth-child(3){animation-delay:2.8s}.poetry-mode-tabs span:nth-child(4),.vocab-mode-tabs span:nth-child(4){animation-delay:4.2s}.poetry-sheet{border:1px solid rgba(22,63,53,.13);border-radius:10px;background:linear-gradient(rgba(43,91,76,.045) 1px,transparent 1px),#ffffffad;background-size:100% 29px;padding:12px 18px;text-align:center;font-family:Songti SC,serif}.poetry-sheet small{color:#7b8f87;font:8px sans-serif}.poetry-sheet p{margin:8px 0 0;font-size:13px;letter-spacing:.12em}.poetry-sheet .poetry-prompt{color:#71847d}.poetry-sheet .poetry-handwriting{color:#a47822;clip-path:inset(0 100% 0 0);animation:handwriting-reveal 8.4s ease-in-out infinite}.poetry-stats,.vocab-session-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:6px}.poetry-stats span,.vocab-session-stats span{border-left:1px solid var(--line);padding-left:8px;color:#7a8e86;font-size:7px}.poetry-stats b,.vocab-session-stats b{color:var(--ink);margin-left:3px;font-size:8px}.vocabulary-practice-demo{min-height:238px;display:grid;grid-template-rows:auto 1fr auto;gap:10px}.vocab-word-card{border:1px solid rgba(22,63,53,.14);border-radius:11px;background:#ffffffad;padding:15px;text-align:center}.vocab-word-card>small{color:#72877f;font-size:8px}.vocab-word-card>strong{display:block;margin:15px 0 5px;font:23px Georgia,serif;letter-spacing:.1em}.vocab-word-card>strong i{font-style:normal}.vocab-word-card>strong em{color:#b65d50;font-style:normal;animation:vocab-error 8.6s ease-in-out infinite}.vocab-word-card>p{margin:0 0 13px;color:#9b746c;font-size:7px}.vocab-word-card>div{display:flex;align-items:center;justify-content:space-between;border-top:1px solid var(--line);padding-top:10px}.vocab-word-card>div span{font:11px Georgia,serif;clip-path:inset(0 100% 0 0);animation:vocab-retype 8.6s ease-in-out infinite}.vocab-word-card>div b{display:flex;align-items:center;gap:4px;color:#3f7865;font-size:7px;opacity:0;animation:vocab-done 8.6s ease-in-out infinite}.learning-trail-demo{min-height:230px;display:grid;grid-template-rows:auto 1fr auto;gap:13px}.trail-summary{display:grid;grid-template-columns:repeat(3,1fr);gap:7px}.trail-summary span{border-left:1px solid var(--line);padding-left:10px}.trail-summary b{display:block;font:19px Georgia,serif}.trail-summary small{color:#7b8e87;font-size:7px}.trail-heatmap{align-self:center;display:grid;grid-template-columns:repeat(7,15px);justify-content:center;gap:6px}.trail-heatmap i,.trail-legend i{width:15px;height:15px;border-radius:2px;background:var(--heat-color, #e8ece8);animation:heat-cell 7.2s ease-in-out infinite;animation-delay:calc(var(--cell) * 38ms)}.trail-heatmap .level-1,.trail-legend .level-1{--heat-color: #d7e4dc}.trail-heatmap .level-2,.trail-legend .level-2{--heat-color: #afc9bc}.trail-heatmap .level-3,.trail-legend .level-3{--heat-color: #739f8b}.trail-heatmap .level-4,.trail-legend .level-4{--heat-color: #2f715a}.trail-heatmap .level-0{--heat-color: #e8ece8}.trail-legend{display:flex;justify-content:center;align-items:center;gap:4px;color:#87978f;font-size:7px}.trail-legend i{width:9px;height:9px;animation:none}@keyframes eraser-sweep{0%,14%{transform:translate(0);opacity:0}20%{opacity:1}48%,78%{transform:translate(118px);opacity:1}88%,to{transform:translate(118px);opacity:0}}@keyframes import-complete{0%,62%{opacity:0;transform:translateY(5px)}72%,92%{opacity:1;transform:translateY(0)}to{opacity:0}}@keyframes write-answer{0%,12%{scale:0 1;opacity:0}38%,82%{scale:1 1;opacity:1}to{scale:0 1;opacity:0}}@keyframes review-next{0%,56%{opacity:.45}68%,88%{opacity:1;box-shadow:0 5px 16px #a1771f1f}to{opacity:.45}}@keyframes similar-link-grow{0%,12%{scale:0 1}34%,88%{scale:1 1}to{scale:0 1}}@keyframes similar-card-in{0%,22%{opacity:.28;transform:translateY(7px)}42%,86%{opacity:1;transform:translateY(0)}to{opacity:.28;transform:translateY(7px)}}@keyframes geometry-step-in{0%,14%{opacity:.42;transform:translate(6px)}32%,82%{opacity:1;transform:translate(0)}to{opacity:.42;transform:translate(6px)}}@keyframes challenge-extract{0%,18%{transform:scale(1)}30%,78%{transform:scale(1.12);box-shadow:0 3px 9px #a5791b29}to{transform:scale(1)}}@keyframes challenge-summary-in{0%,36%{opacity:.35;transform:translate(7px)}52%,88%{opacity:1;transform:translate(0)}to{opacity:.35;transform:translate(7px)}}@keyframes vocab-error{0%,18%{color:inherit}25%,42%{color:#b65d50;text-decoration:underline}50%,to{color:inherit;text-decoration:none}}@keyframes vocab-retype{0%,48%{clip-path:inset(0 100% 0 0)}72%,90%{clip-path:inset(0 0 0 0)}to{clip-path:inset(0 100% 0 0)}}@keyframes vocab-done{0%,70%{opacity:0}80%,92%{opacity:1}to{opacity:0}}@keyframes demo-progress{0%{transform:translate(-105%)}82%,to{transform:translate(360%)}}@keyframes line-grow{0%,8%{transform:scaleX(.08);opacity:.35}34%,78%{transform:scaleX(1);opacity:1}to{transform:scaleX(.08);opacity:.35}}@keyframes caret-blink{50%{opacity:0}}@keyframes source-term-highlight{0%,7%{background:transparent;color:inherit}12%,88%{background:#f2dfaa;color:#765616}96%,to{background:transparent;color:inherit}}@keyframes source-term-highlight-2{0%,11%{background:transparent;color:inherit}16%,88%{background:#f2dfaa;color:#765616}96%,to{background:transparent;color:inherit}}@keyframes source-term-highlight-3{0%,15%{background:transparent;color:inherit}20%,88%{background:#f2dfaa;color:#765616}96%,to{background:transparent;color:inherit}}@keyframes source-term-highlight-4{0%,19%{background:transparent;color:inherit}24%,88%{background:#f2dfaa;color:#765616}96%,to{background:transparent;color:inherit}}@keyframes source-term-highlight-5{0%,23%{background:transparent;color:inherit}28%,88%{background:#f2dfaa;color:#765616}96%,to{background:transparent;color:inherit}}@keyframes query-tag-one{0%,28%{opacity:0;transform:translateY(6px) scale(.94)}33%,90%{opacity:1;transform:none}97%,to{opacity:0;transform:translateY(-3px)}}@keyframes query-tag-two{0%,32%{opacity:0;transform:translateY(6px) scale(.94)}37%,90%{opacity:1;transform:none}97%,to{opacity:0;transform:translateY(-3px)}}@keyframes query-tag-three{0%,36%{opacity:0;transform:translateY(6px) scale(.94)}41%,90%{opacity:1;transform:none}97%,to{opacity:0;transform:translateY(-3px)}}@keyframes query-tag-four{0%,40%{opacity:0;transform:translateY(6px) scale(.94)}45%,90%{opacity:1;transform:none}97%,to{opacity:0;transform:translateY(-3px)}}@keyframes query-tag-five{0%,44%{opacity:0;transform:translateY(6px) scale(.94)}49%,90%{opacity:1;transform:none}97%,to{opacity:0;transform:translateY(-3px)}}@keyframes precision-match-note{0%,50%{opacity:0;transform:translateY(3px)}57%,90%{opacity:1;transform:none}97%,to{opacity:0}}@keyframes precision-result-in{0%,55%{opacity:0;transform:translateY(8px)}63%,90%{opacity:1;transform:none}97%,to{opacity:0;transform:translateY(-3px)}}@keyframes result-term-highlight{0%,63%{background:transparent;color:inherit}70%,90%{background:#d5ebe2;color:#276853;box-shadow:inset 0 -1px #6fa38f}97%,to{background:transparent;color:inherit;box-shadow:none}}@keyframes source-question{0%,to{transform:translateY(0)}30%,70%{transform:translateY(-8px) scale(1.04)}}@keyframes paper-pick-scene{0%,2%{opacity:0;transform:translate(18px)}6%,29%{opacity:1;transform:none}34%,to{opacity:0;transform:translate(-16px)}}@keyframes paper-layout-scene{0%,29%{opacity:0;transform:translate(18px)}35%,64%{opacity:1;transform:none}69%,to{opacity:0;transform:translate(-16px)}}@keyframes paper-print-scene{0%,64%{opacity:0;transform:translate(18px)}70%,94%{opacity:1;transform:none}99%,to{opacity:0;transform:translate(-8px)}}@keyframes paper-check-one{0%,8%{background:transparent;border-color:#9fb2aa}12%,33%{background:#4d8b75;border-color:#4d8b75}36%,to{background:transparent}}@keyframes paper-check-two{0%,13%{background:transparent;border-color:#9fb2aa}17%,33%{background:#4d8b75;border-color:#4d8b75}36%,to{background:transparent}}@keyframes paper-check-three{0%,18%{background:transparent;border-color:#9fb2aa}22%,33%{background:#4d8b75;border-color:#4d8b75}36%,to{background:transparent}}@keyframes paper-check-icon-one{0%,8%{opacity:0}12%,33%{opacity:1}36%,to{opacity:0}}@keyframes paper-check-icon-two{0%,13%{opacity:0}17%,33%{opacity:1}36%,to{opacity:0}}@keyframes paper-check-icon-three{0%,18%{opacity:0}22%,33%{opacity:1}36%,to{opacity:0}}@keyframes paper-action-press{0%,24%{transform:scale(.96)}28%{transform:scale(.9)}31%,to{transform:scale(.96)}}@keyframes paper-control-font{0%,36%{border-color:#163f351f;background:#f9f8f3}41%,47%{border-color:#d0aa52;background:#fbf3de}52%,to{border-color:#163f351f;background:#f9f8f3}}@keyframes paper-control-gap{0%,45%{border-color:#163f351f;background:#f9f8f3}50%,56%{border-color:#d0aa52;background:#fbf3de}61%,to{border-color:#163f351f;background:#f9f8f3}}@keyframes paper-control-space{0%,54%{border-color:#163f351f;background:#f9f8f3}59%,65%{border-color:#d0aa52;background:#fbf3de}70%,to{border-color:#163f351f;background:#f9f8f3}}@keyframes paper-question-spacing{0%,40%{margin-bottom:4px;padding-bottom:2px;font-size:6.5px}57%,68%{margin-bottom:12px;padding-bottom:7px;font-size:7.5px}72%,to{margin-bottom:9px;padding-bottom:5px;font-size:7px}}@keyframes paper-preview-settle{0%,67%{transform:translateY(8px) scale(.9);opacity:.4}75%,94%{transform:none;opacity:1}to{transform:translateY(-3px) scale(.96);opacity:0}}@keyframes paper-ready-in{0%,75%{opacity:0;transform:translateY(4px)}82%,94%{opacity:1;transform:none}to{opacity:0}}@keyframes geometry-turn{0%,to{transform:rotate(-4deg)}50%{transform:rotate(8deg) scale(1.05);color:var(--gold)}}@keyframes method-step{0%,18%{color:#60786f;border-color:#b8c7c1}38%,66%{color:#9b711e;border-color:var(--gold)}to{color:#60786f;border-color:#b8c7c1}}@keyframes challenge-pick{0%,24%,to{transform:scale(.96);opacity:.55}42%,78%{transform:scale(1.08);opacity:1;box-shadow:0 8px 20px #b88a3129}}@keyframes mode-cycle{0%,16%,to{background:transparent;color:#778b83}24%,48%{background:var(--ink);color:#fff;border-color:var(--ink)}}@keyframes poetry-hide{0%,22%{opacity:.35}42%,78%{opacity:1}to{opacity:.35}}@keyframes handwriting-reveal{0%,38%{clip-path:inset(0 100% 0 0)}68%,86%{clip-path:inset(0 0 0 0)}to{clip-path:inset(0 100% 0 0)}}@keyframes import-paper{0%,to{transform:translateY(0)}30%,56%{transform:translateY(-5px);border-color:var(--gold)}}@keyframes output-ready{0%,28%,to{opacity:.28;transform:translate(-5px)}48%,78%{opacity:1;transform:none;color:var(--ink)}}@keyframes article-source-scene{0%,2%{opacity:0;transform:translate(18px)}6%,29%{opacity:1;transform:none}34%,to{opacity:0;transform:translate(-16px)}}@keyframes article-paste-scene{0%,29%{opacity:0;transform:translate(18px)}35%,61%{opacity:1;transform:none}66%,to{opacity:0;transform:translate(-16px)}}@keyframes article-result-scene{0%,61%{opacity:0;transform:translate(18px)}68%,95%{opacity:1;transform:none}to{opacity:0;transform:translate(-8px)}}@keyframes article-text-select{0%,9%{background-size:0 100%}19%,30%{background-size:100% 100%}34%,to{background-size:0 100%}}@keyframes article-copy-tip{0%,18%{opacity:0;transform:translateY(4px)}23%,30%{opacity:1;transform:none}34%,to{opacity:0}}@keyframes article-paste-text{0%,36%{opacity:0}41%,61%{opacity:1}66%,to{opacity:0}}@keyframes article-paste-caret{0%,35%,66%,to{opacity:0}38%,64%{opacity:1}51%{opacity:.2}}@keyframes article-generate-press{0%,54%{transform:scale(1)}58%{transform:scale(.92)}61%,to{transform:scale(1)}}@keyframes article-output-one{0%,68%{opacity:0;transform:translateY(5px)}73%,95%{opacity:1;transform:none}to{opacity:0}}@keyframes article-output-two{0%,72%{opacity:0;transform:translateY(5px)}77%,95%{opacity:1;transform:none}to{opacity:0}}@keyframes article-output-three{0%,76%{opacity:0;transform:translateY(5px)}81%,95%{opacity:1;transform:none}to{opacity:0}}@keyframes article-output-four{0%,80%{opacity:0;transform:translateY(5px)}85%,95%{opacity:1;transform:none}to{opacity:0}}@keyframes vocab-mode{0%,14%,to{background:#ffffff80;border-color:var(--line);transform:none}22%,44%{background:#f4ead1;border-color:#d4ab55;transform:translateY(-3px)}}@keyframes movie-watch-scene{0%,2%{opacity:0;transform:translate(18px)}6%,52%{opacity:1;transform:none}58%,to{opacity:0;transform:translate(-16px)}}@keyframes movie-practice-scene{0%,52%{opacity:0;transform:translate(18px)}59%,95%{opacity:1;transform:none}to{opacity:0;transform:translate(-8px)}}@keyframes movie-en-toggle{0%,9%{background:#f2f0e7;color:#274f42}17%,52%{background:#ffffff1a;color:#ffffffad}58%,to{background:none}}@keyframes movie-cn-toggle{0%,9%{background:transparent;color:#ffffffad}17%,52%{background:#f2f0e7;color:#274f42}58%,to{background:none}}@keyframes movie-english-subtitle{0%,9%{opacity:1}16%,23%{opacity:.28}29%,52%{opacity:1}58%,to{opacity:0}}@keyframes movie-chinese-subtitle{0%,11%{opacity:.28}18%,52%{opacity:1}58%,to{opacity:0}}@keyframes movie-word-highlight{0%,22%{background:transparent;color:inherit}28%,52%{background:#e6cf83;color:#3b331e}58%,to{background:transparent}}@keyframes movie-word-action{0%,25%{opacity:0;transform:translateY(4px)}31%,52%{opacity:1;transform:none}58%,to{opacity:0}}@keyframes movie-word-add{0%,34%{transform:scale(1)}38%{transform:scale(.9)}42%,to{transform:scale(1)}}@keyframes movie-tip-show{0%,36%{opacity:0;transform:translateY(4px)}42%,52%{opacity:1;transform:none}58%,to{opacity:0}}@keyframes movie-line-type{0%,59%{width:0}80%,95%{width:100%}to{width:0}}@keyframes movie-input-caret{0%,58%,to{opacity:0}61%,94%{opacity:1}72%,86%{opacity:.2}}@keyframes movie-completion-show{0%,79%{opacity:0;transform:translateY(5px)}85%,95%{opacity:1;transform:none}to{opacity:0}}@keyframes lab-part-early{0%,3%{opacity:0;transform:translate(-8px,9px) scale(.82)}8%,94%{opacity:1;transform:none}to{opacity:0;transform:scale(.95)}}@keyframes lab-part-second{0%,7%{opacity:0;transform:translateY(9px) scale(.84)}13%,94%{opacity:1;transform:none}to{opacity:0;transform:scale(.95)}}@keyframes lab-part-third{0%,11%{opacity:0;transform:translateY(9px) scale(.84)}17%,94%{opacity:1;transform:none}to{opacity:0;transform:scale(.95)}}@keyframes lab-part-fourth{0%,15%{opacity:0;transform:translateY(9px) scale(.84)}21%,94%{opacity:1;transform:none}to{opacity:0;transform:scale(.95)}}@keyframes lab-meter-enter{0%,18%{opacity:0;transform:translateY(9px) scale(.84)}24%,52%{opacity:1;transform:none}60%,84%{opacity:1;transform:scale(1.34);filter:drop-shadow(0 13px 18px rgba(37,65,55,.18))}91%,94%{opacity:1;transform:none;filter:none}to{opacity:0;transform:scale(.95)}}@keyframes lab-wire-build{0%,11%{stroke-dashoffset:640;opacity:0}13%{opacity:1}28%,94%{stroke-dashoffset:0;opacity:1}to{stroke-dashoffset:0;opacity:0}}@keyframes lab-wire-build-late{0%,17%{stroke-dashoffset:640;opacity:0}19%{opacity:1}33%,94%{stroke-dashoffset:0;opacity:1}to{stroke-dashoffset:0;opacity:0}}@keyframes lab-switch-open{0%,31%{opacity:1}32%,94%{opacity:0}to{opacity:1}}@keyframes lab-switch-closed{0%,31%{opacity:0}32%,94%{opacity:1}to{opacity:0}}@keyframes lab-rheostat-adjust{0%,42%{left:80%}58%{left:58%}76%,94%{left:24%}to{left:80%}}@keyframes lab-lamp-brightness{0%,31%{opacity:0;transform:translate(-50%,-50%) scale(.7)}36%,45%{opacity:.28;transform:translate(-50%,-50%) scale(.78)}59%{opacity:.58;transform:translate(-50%,-50%) scale(.96)}76%,91%{opacity:.96;transform:translate(-50%,-50%) scale(1.18)}to{opacity:0;transform:translate(-50%,-50%) scale(.7)}}@keyframes lab-lamp-image{0%,31%{filter:brightness(1) saturate(1)}45%{filter:brightness(1.06) saturate(1.08)}60%{filter:brightness(1.13) saturate(1.18)}76%,91%{filter:brightness(1.24) saturate(1.34) drop-shadow(0 0 8px rgba(240,179,35,.34))}to{filter:brightness(1) saturate(1)}}@keyframes lab-ammeter-needle{0%,31%{transform:rotate(-160deg)}43%{transform:rotate(-149deg)}59%{transform:rotate(-144deg)}76%,94%{transform:rotate(-139deg)}to{transform:rotate(-160deg)}}@keyframes lab-voltmeter-needle{0%,31%{transform:rotate(-160deg)}43%{transform:rotate(-134deg)}59%{transform:rotate(-122deg)}76%,94%{transform:rotate(-113deg)}to{transform:rotate(-160deg)}}@keyframes lab-reading-pop{0%,50%{opacity:0;transform:translate(-50%,4px)}59%,88%{opacity:1;transform:translate(-50%)}94%,to{opacity:0;transform:translate(-50%,4px)}}@keyframes lab-reading-one{0%,51%{opacity:1}52%,to{opacity:0}}@keyframes lab-reading-two{0%,51%{opacity:0}52%,67%{opacity:1}68%,to{opacity:0}}@keyframes lab-reading-three{0%,67%{opacity:0}68%,94%{opacity:1}95%,to{opacity:0}}@keyframes lab-caption-build{0%,5%{opacity:0;transform:translateY(4px)}10%,24%{opacity:1;transform:none}30%,to{opacity:0}}@keyframes lab-caption-switch{0%,27%{opacity:0;transform:translateY(4px)}32%,39%{opacity:1;transform:none}45%,to{opacity:0}}@keyframes lab-caption-adjust{0%,42%{opacity:0;transform:translateY(4px)}49%,88%{opacity:1;transform:none}94%,to{opacity:0}}@keyframes heat-cell{0%,12%{background:#e8ece8;transform:scale(.7);opacity:.35}36%,82%{background:var(--heat-color);transform:scale(1);opacity:1}to{background:#e8ece8;transform:scale(.7);opacity:.35}}.closing{text-align:center;padding:92px 30px 112px}.closing>p{color:#81928b;letter-spacing:.16em;font-size:12px}.closing h2{margin:18px auto 44px;font-family:Songti SC,serif;font-size:clamp(38px,4.2vw,62px);font-weight:500}.closing-actions{display:flex;align-items:center;justify-content:center;gap:14px;flex-wrap:wrap}.button{min-height:50px;padding:0 26px;border-radius:5px;border:1px solid var(--ink);display:inline-flex;align-items:center;justify-content:center;gap:7px;cursor:pointer}.button-primary{background:var(--ink);color:#fff}.button-secondary{background:transparent;color:var(--ink)}.button-text{border-color:transparent;color:#617970}footer{width:min(1320px,calc(100% - 80px));margin:0 auto;border-top:1px solid var(--line);padding:40px 0 48px;display:flex;justify-content:space-between;align-items:flex-end;color:#788d85}footer p{margin:0;font-size:12px}.footer-mark .wordmark-logo{width:46px;height:46px;flex-basis:46px;border-radius:14px}.footer-mark .wordmark-copy strong{font-size:22px}.footer-mark .wordmark-copy>span{font-size:6px}.feature-experience-page{position:fixed;top:0;right:0;bottom:0;left:0;z-index:120;overflow-y:auto;background:#f7f4ed;color:var(--ink)}.experience-header{position:sticky;top:0;z-index:8;height:76px;padding:0 max(32px,calc((100vw - 1180px)/2));border-bottom:1px solid var(--line);background:#f7f4edeb;-webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px);display:grid;grid-template-columns:1fr auto 1fr;align-items:center}.experience-header>button{justify-self:start;border:0;background:transparent;padding:10px 0;display:inline-flex;align-items:center;gap:7px;color:#527067;font-size:13px;cursor:pointer}.experience-header>span{color:#879890;font-size:11px;letter-spacing:.12em}.experience-header .experience-close{justify-self:end;width:42px;height:42px;padding:0;border:1px solid var(--line);border-radius:50%;display:grid;place-items:center}.playback-main{width:min(1120px,calc(100% - 64px));margin:0 auto;padding:54px 0 76px}.playback-heading{margin-bottom:28px;display:flex;align-items:center;gap:16px}.playback-icon,.detail-icon{width:52px;height:52px;flex:0 0 auto;border:1px solid var(--line);border-radius:50%;background:#edf1ea;display:grid;place-items:center}.playback-heading p{margin:0 0 5px;color:#879890;font-size:10px;letter-spacing:.1em}.playback-heading h1{margin:0;font:500 clamp(34px,4vw,52px)/1.15 "Songti SC","STSong",serif}.feature-video-frame{position:relative;width:100%;aspect-ratio:16 / 9;border:1px solid rgba(22,63,53,.18);border-radius:18px;overflow:hidden;background:#112820;box-shadow:0 30px 80px #1b302824}.feature-video-frame video{display:block;width:100%;height:100%;object-fit:contain;background:#112820}.feature-video-frame.video-unavailable video{filter:brightness(.46) saturate(.72)}.video-missing-state{position:absolute;top:0;right:0;bottom:0;left:0;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;color:#ffffffeb;background:#0d241d61;pointer-events:none}.video-missing-state strong{margin:16px 0 7px;font:500 21px Songti SC,serif}.video-missing-state span{max-width:390px;color:#ffffff9e;font-size:11px;line-height:1.7}.playback-summary{margin-top:30px;padding:0 4px;display:flex;justify-content:space-between;align-items:flex-end;gap:34px}.playback-summary h2{margin:0 0 10px;font:500 27px Songti SC,serif}.playback-summary p{max-width:660px;margin:0;color:#657c74;font-size:14px;line-height:1.8}.detail-link{flex:0 0 auto;min-height:48px;padding:0 20px;border:1px solid rgba(22,63,53,.28);border-radius:999px;background:transparent;color:var(--ink);display:inline-flex;align-items:center;gap:11px;cursor:pointer;transition:background .25s ease,color .25s ease}.detail-link:hover{background:var(--ink);color:#fff}.detail-main{width:min(1120px,calc(100% - 64px));margin:0 auto;padding:44px 0 86px}.detail-main section{border-bottom:1px solid var(--line)}.detail-hero{min-height:470px;display:grid;grid-template-columns:1fr .82fr;gap:64px;align-items:center;padding:30px 0 74px}.detail-hero-copy .eyebrow,.detail-origin .eyebrow,.detail-section-heading .eyebrow,.detail-highlights .eyebrow{margin:22px 0 14px}.detail-hero h1{max-width:620px;margin:0 0 20px;font:500 clamp(40px,4.2vw,56px)/1.22 "Songti SC","STSong",serif;letter-spacing:-.025em}.detail-hero-copy>p:last-child{max-width:570px;color:#60776e;font-size:16px;line-height:1.85}.detail-hero img{display:block;width:100%;aspect-ratio:4 / 5;object-fit:cover;border:1px solid var(--line);border-radius:18px;box-shadow:var(--shadow)}.detail-origin{padding:88px 0;display:grid;grid-template-columns:.7fr 1.3fr;column-gap:70px}.detail-origin .eyebrow{grid-column:1 / -1}.detail-origin h2,.detail-section-heading h2,.detail-highlights h2{margin:0;font:500 clamp(28px,3vw,36px)/1.3 "Songti SC",serif}.detail-origin>p:last-child{margin:0;color:#60776e;font-size:16px;line-height:2}.feature-storyboard{padding:88px 0 96px}.storyboard-heading{max-width:760px}.storyboard-heading>p:last-child{margin:18px 0 0;max-width:690px;color:#60776e;font-size:15px;line-height:1.9}.storyboard-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:22px}.storyboard-card{padding:18px;border:1px solid var(--line);border-radius:18px;background:#ffffff57}.storyboard-caption{min-height:58px;margin:0 2px 16px;display:grid;grid-template-columns:38px 1fr;gap:12px;align-items:start}.storyboard-caption>span{color:var(--gold);font:18px/1.35 Georgia,serif}.storyboard-caption b,.storyboard-caption small{display:block}.storyboard-caption b{margin-bottom:5px;font:600 17px/1.35 Songti SC,serif}.storyboard-caption small{color:#7b8e87;font-size:11px;line-height:1.55}.storyboard-screen{min-height:280px;padding:20px;border:1px solid rgba(22,63,53,.13);border-radius:13px;background:#fbfaf5;box-shadow:0 18px 45px #26393112;overflow:hidden}.storyboard-screen header{min-height:31px;margin:-3px 0 18px;padding-bottom:12px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;color:#6d817a;font-size:11px}.corrected-screen>p{min-height:67px;margin:0 0 16px;font:500 15px/1.65 Songti SC,serif}.answer-compare{display:grid;grid-template-columns:1fr 1fr;gap:9px}.answer-compare>span{min-height:63px;padding:10px 11px;border-radius:8px;background:#f2efe7}.answer-compare small,.answer-compare b,.answer-compare del{display:block}.answer-compare small{margin-bottom:7px;color:#87958f;font-size:9px}.answer-compare del{color:#a76b60;font-size:13px}.answer-compare b{color:#39715f;font-size:13px}.corrected-screen>em{margin-top:16px;min-height:30px;padding:0 10px;border-radius:999px;background:#e6efe8;color:#3f725f;display:inline-flex;align-items:center;gap:6px;font-size:10px;font-style:normal}.feature-source{margin-bottom:14px;padding:15px;border-left:3px solid var(--gold);background:#f3efe5}.feature-source small,.feature-source strong{display:block}.feature-source small{margin-bottom:6px;color:#8b958d;font-size:9px}.feature-source strong{font:600 16px Songti SC,serif}.feature-tags{display:flex;flex-wrap:wrap;gap:7px}.feature-tags span{padding:7px 9px;border:1px solid rgba(55,111,91,.2);border-radius:999px;background:#edf3ed;color:#497467;font-size:10px}.feature-screen>p{margin:19px 0 0;color:#788b83;font-size:11px;line-height:1.7}.variants-screen>div{position:relative;min-height:76px;margin-top:9px;padding:12px 73px 12px 12px;border:1px solid rgba(22,63,53,.11);border-radius:9px;background:#f7f5ee}.variants-screen>div>span{color:var(--gold);font-size:9px;letter-spacing:.08em}.variants-screen>div p{margin:6px 0 0;font:500 12px/1.55 Songti SC,serif}.variants-screen>div b{position:absolute;right:9px;top:50%;transform:translateY(-50%);color:#4c786a;font-size:9px;font-weight:500}.mastery-score{display:flex;align-items:center;gap:14px}.mastery-score strong{font:500 52px/1 Georgia,serif;color:#2f6656}.mastery-score span{color:#627970;font-size:11px;line-height:1.6}.mastery-progress{margin:18px 0;display:grid;grid-template-columns:repeat(3,1fr);gap:6px}.mastery-progress i{height:5px;border-radius:999px;background:#5c8a78}.mastery-screen>p{min-height:38px;margin:0 0 13px;color:#587267;display:flex;align-items:flex-start;gap:7px;font-size:10px;line-height:1.6}.mastery-screen>p svg{flex:0 0 auto;margin-top:2px}.mastery-screen button{width:100%;min-height:35px;border:0;border-radius:8px;background:var(--ink);color:#fff;display:flex;align-items:center;justify-content:center;gap:7px;font-size:10px}.walkthrough-screen{display:flex;flex-direction:column}.walkthrough-lead small,.walkthrough-lead strong{display:block}.walkthrough-lead small{margin-bottom:8px;color:#8a9891;font-size:9px;line-height:1.5}.walkthrough-lead strong{font:600 17px/1.55 Songti SC,serif}.walkthrough-body{margin:13px 0 0;color:#697f76;font-size:11px;line-height:1.75}.walkthrough-chips{margin-top:16px;display:flex;flex-wrap:wrap;gap:7px}.walkthrough-chips span{min-height:27px;padding:0 9px;border:1px solid rgba(55,111,91,.18);border-radius:999px;background:#edf3ed;color:#497467;display:inline-flex;align-items:center;font-size:9px}.walkthrough-rows{margin-top:16px;border-top:1px solid var(--line)}.walkthrough-rows>div{min-height:37px;border-bottom:1px solid rgba(22,63,53,.09);display:flex;align-items:center;justify-content:space-between;gap:16px;font-size:10px}.walkthrough-rows span{color:#75877f}.walkthrough-rows b{color:#376858;font-weight:600;text-align:right}.walkthrough-status{margin-top:auto;padding-top:14px;color:#427360;display:flex;align-items:center;gap:7px;font-size:10px}.walkthrough-metric{display:flex;align-items:center;gap:15px}.walkthrough-metric>strong{color:#2f6656;font:500 45px/1 Georgia,serif;letter-spacing:-.04em}.walkthrough-metric>span{color:#627970;font-size:10px;line-height:1.55}.walkthrough-metric>span>span{display:block}.walkthrough-action{margin-top:auto;min-height:36px;padding:0 12px;border-radius:8px;background:var(--ink);color:#fff;display:flex;align-items:center;justify-content:center;gap:7px;font-size:10px}.walkthrough-action svg:last-child{margin-left:auto}.detail-process{padding:88px 0 96px}.detail-section-heading{max-width:680px;margin-bottom:44px}.detail-step-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.detail-step-grid article{min-height:190px;padding:24px;border:1px solid var(--line);border-radius:16px;background:#ffffff61}.detail-step-grid span{display:block;margin-bottom:40px;color:var(--gold);font:20px Georgia,serif}.detail-step-grid p{margin:0;font:500 18px/1.7 Songti SC,serif}.detail-highlights{padding:88px 0;display:grid;grid-template-columns:1.1fr .9fr;gap:70px}.detail-highlights ul{margin:0;padding:0;list-style:none;display:grid;gap:12px}.detail-highlights li{min-height:56px;padding:0 18px;border-bottom:1px solid var(--line);display:flex;align-items:center;gap:12px;color:#4f6f64}.detail-highlights li svg{color:var(--gold)}.detail-back-to-video{padding:52px 0 0;border-bottom:0!important;display:flex;justify-content:space-between;align-items:center}.detail-back-to-video small{display:block;margin-bottom:8px;color:#81928b;font-size:10px;letter-spacing:.12em}.detail-back-to-video p{margin:0;font:500 24px Songti SC,serif}.detail-back-to-video button{min-height:46px;padding:0 20px;border:0;border-radius:999px;background:var(--ink);color:#fff;display:inline-flex;align-items:center;gap:9px;cursor:pointer}.dialog-backdrop{position:fixed;top:0;right:0;bottom:0;left:0;z-index:100;background:#0e251f5c;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);display:grid;place-items:center;padding:24px}.feature-dialog{width:min(620px,100%);max-height:calc(100dvh - 48px);overflow-y:auto;overflow-x:hidden;scrollbar-width:thin;background:#fbf9f3;border:1px solid rgba(255,255,255,.6);border-radius:20px;box-shadow:0 30px 100px #112c2438;padding:48px;position:relative}.dialog-topbar{position:sticky;z-index:4;top:-28px;margin:-28px -28px -12px;display:flex;justify-content:flex-end;pointer-events:none}.dialog-topbar>span{display:none}.dialog-close{width:40px;height:40px;border:1px solid var(--line);border-radius:50%;background:#fbf9f3eb;-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);display:grid;place-items:center;cursor:pointer;pointer-events:auto}.dialog-icon{width:58px;height:58px;border-radius:50%;background:var(--sage);display:grid;place-items:center;margin-bottom:25px}.feature-dialog h2{font:500 42px Songti SC,serif;margin:0 0 18px}.feature-dialog>p:not(.eyebrow):not(.dialog-note){color:#5e766d;line-height:1.9}.dialog-demo{border:1px solid var(--line);background:#f5f2e9;border-radius:14px;padding:30px;margin:28px 0 20px;overflow:hidden}.dialog-note{font-size:12px;color:#8a9893;margin:0 0 28px}@media(max-width:900px){.site-header,.section-heading,footer{width:calc(100% - 48px)}.hero{width:calc(100% - 64px)}.site-header nav{gap:17px}.feature-rail-shell{width:calc(100% - 48px)}.feature-track{padding-left:36px;padding-right:36px}.feature-card{flex-basis:286px}}@media(max-width:720px){.site-header{height:68px;width:calc(100% - 32px)}.wordmark{gap:10px}.wordmark-logo{width:52px;height:52px;flex-basis:52px;border-radius:15px}.wordmark-copy strong{font-size:23px;letter-spacing:.08em}.menu-toggle{display:block;width:44px;height:44px;margin-right:-8px}.site-header nav{display:none;position:fixed;z-index:30;top:76px;left:16px;right:16px;min-width:0;max-height:calc(100dvh - 92px);overflow-y:auto;background:#fbf9f3fa;border:1px solid var(--line);border-radius:16px;box-shadow:0 24px 70px #173f352b;padding:12px;flex-direction:column;align-items:stretch;gap:2px;-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px)}.site-header nav.open{display:flex}.site-header nav a,.nav-apply{min-height:48px;padding:0 14px;text-align:left;display:flex;align-items:center;border-radius:9px}.site-header nav a:hover,.nav-apply:hover{background:#f0eee7}.nav-login{border:0;margin-top:6px;background:var(--ink);color:#fff!important;border-radius:9px;justify-content:center}.login-page{padding:0 16px 42px}.login-page-header{min-height:68px}.login-page-header .wordmark-copy strong{font-size:23px}.login-page-header .wordmark-copy>span{font-size:7px}.login-card{margin-top:54px;padding:30px 22px;border-radius:15px}.login-mark{width:46px;height:46px;margin-bottom:22px}.hero{width:calc(100% - 32px);padding:58px 0 62px}.eyebrow{margin-bottom:16px;font-size:10px;line-height:1.6}.hero h1{max-width:12em;font-size:clamp(38px,11vw,46px);line-height:1.12;letter-spacing:-.045em}.hero-rule{margin:31px 0 27px}.hero-copy{font-size:15px;line-height:1.82;margin-bottom:13px}.features-section{padding:58px 0 62px}.section-heading{width:calc(100% - 32px);margin-bottom:22px;align-items:flex-start}.section-heading h2{max-width:9em;font-size:32px;line-height:1.28}.rail-controls{display:none}.feature-rail-shell{width:100%}.feature-rail-edge{display:none}.feature-track{gap:14px;padding:12px 8vw 28px;scroll-padding-inline:8vw}.feature-card{flex-basis:min(82vw,330px);min-height:428px;border-radius:18px}.feature-card:hover,.feature-card.active{transform:translateY(-4px) scale(1.01)}.card-visual{height:266px}.card-play{opacity:1;transform:none;left:14px;bottom:14px;min-height:31px;font-size:10px}.card-copy{padding:18px 18px 22px}.card-title-row{gap:10px}.card-number{font-size:33px}.card-copy h3{font-size:22px}.card-copy p{font-size:13px}.closing{padding:58px 16px 70px}.closing h2{font-size:36px;line-height:1.25;margin-bottom:34px}.closing-actions{width:100%;flex-direction:column}.closing-actions .button{width:min(100%,360px);min-height:50px}footer{width:calc(100% - 32px);padding:34px 0 40px;flex-direction:column;align-items:flex-start;gap:20px}.dialog-backdrop{padding:0;display:block;background:#0e251f80;-webkit-backdrop-filter:blur(5px);backdrop-filter:blur(5px)}.feature-dialog{width:100%;height:100dvh;max-height:none;padding:0 16px calc(28px + env(safe-area-inset-bottom));border:0;border-radius:0;box-shadow:none}.dialog-topbar{top:0;height:64px;margin:0 -16px 20px;padding:env(safe-area-inset-top) 8px 0 18px;background:#fbf9f3f0;border-bottom:1px solid var(--line);align-items:center;justify-content:space-between;-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);pointer-events:auto}.dialog-topbar>span{display:block;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;font:600 17px Songti SC,STSong,serif}.dialog-close{flex:0 0 44px;width:44px;height:44px;border:0;background:transparent;-webkit-backdrop-filter:none;backdrop-filter:none}.dialog-icon,.feature-dialog>.eyebrow,.feature-dialog>h2{display:none}.feature-dialog>p:not(.eyebrow):not(.dialog-note){margin:0 2px 18px;font-size:15px;line-height:1.75}.dialog-demo{margin:16px 0 18px;padding:16px;border-radius:14px}.demo-status{margin:-2px 0 16px;gap:12px}.dialog-note{margin:0 2px 22px;font-size:12px;line-height:1.65}.feature-dialog>.button{width:100%;min-height:50px}.experience-header{height:64px;padding:0 16px}.experience-header>button{font-size:12px}.experience-header>span{display:none}.experience-header .experience-close{width:40px;height:40px;border:0}.playback-main,.detail-main{width:calc(100% - 32px);padding-top:28px}.playback-heading{margin-bottom:18px;gap:12px}.playback-icon{width:44px;height:44px}.playback-heading h1{font-size:34px}.playback-heading p{font-size:8px}.feature-video-frame{border-radius:12px}.video-missing-state strong{font-size:17px}.video-missing-state span{display:none}.playback-summary{margin-top:22px;padding:0;flex-direction:column;align-items:stretch;gap:22px}.playback-summary h2{font-size:23px}.playback-summary p{font-size:14px}.detail-link{width:100%;justify-content:center}.detail-main{padding-bottom:58px}.detail-hero{min-height:0;grid-template-columns:1fr;gap:28px;padding:10px 0 48px}.detail-hero h1{font-size:38px}.detail-hero img{order:-1;aspect-ratio:16 / 10;border-radius:13px}.detail-origin{padding:54px 0;grid-template-columns:1fr;row-gap:20px}.detail-origin h2,.detail-section-heading h2,.detail-highlights h2{font-size:30px}.detail-origin>p:last-child{font-size:15px;line-height:1.85}.feature-storyboard{padding:54px 0 60px}.storyboard-heading>p:last-child{font-size:14px;line-height:1.8}.storyboard-grid{grid-template-columns:1fr;gap:12px}.storyboard-card{padding:13px;border-radius:14px}.storyboard-screen{min-height:258px;padding:16px}.detail-process{padding:54px 0 60px}.detail-section-heading{margin-bottom:28px}.detail-step-grid{grid-template-columns:1fr;gap:10px}.detail-step-grid article{min-height:118px;padding:18px;display:grid;grid-template-columns:48px 1fr;align-items:start;gap:10px}.detail-step-grid span{margin:1px 0 0}.detail-step-grid p{font-size:17px}.detail-highlights{padding:54px 0;grid-template-columns:1fr;gap:28px}.detail-back-to-video{padding-top:36px;flex-direction:column;align-items:stretch;gap:16px}.detail-back-to-video p{margin:0;font-size:21px}.detail-back-to-video button{justify-content:center}.paper-composer-demo,.article-import-demo,.movie-learning-demo{min-height:270px}.paper-scene,.article-scene,.movie-scene{max-width:100%}.paper-layout-body{height:210px;grid-template-columns:1fr;grid-template-rows:auto 1fr;gap:6px}.paper-controls{grid-template-columns:repeat(3,minmax(0,1fr));gap:4px}.paper-control{height:31px;padding:0 4px;grid-template-columns:1fr;justify-items:center;font-size:7px}.paper-control svg,.paper-control b{display:none}.paper-layout-sheet{min-height:145px;padding:8px 10px}.paper-print-sheet{width:91%;padding:11px 12px}.article-source-body{padding:15px 14px 10px}.article-source-body strong{font-size:14px}.article-source-body p{font-size:9px;line-height:1.55}.article-paste-scene,.article-result-scene{padding:11px}.article-result-body{height:214px;grid-template-columns:1fr;grid-template-rows:112px 1fr;gap:6px;padding-top:8px}.article-bilingual-card{padding:8px 10px}.article-bilingual-card button{float:left;width:24px;height:24px;margin:0 8px 4px 0}.article-bilingual-card p{font-size:9px;line-height:1.5}.article-bilingual-card small{font-size:7px;margin-top:4px}.article-output-grid>span{padding:6px}.movie-watch-scene{grid-template-rows:142px auto auto}.movie-practice-input{height:64px;padding:0 10px;font-size:10px}.movie-completion-line{padding:7px 8px}.lab-stage{min-height:190px;aspect-ratio:1.42}.lab-caption{left:10px;bottom:8px;font-size:8px}.heatmap-demo>div{gap:6px}.heatmap-demo i{width:14px;height:14px}.wrong-import-demo{min-height:420px;grid-template-columns:1fr;gap:7px}.wrong-import-demo>svg{margin:-3px auto;transform:rotate(90deg)}.wrong-import-step{height:126px;padding:9px}.wrong-import-step>small{margin-bottom:7px}.wrong-import-paper{height:87px;padding:9px 11px;line-height:1.55}.wrong-import-paper b{margin-top:5px}.eraser-pass{top:43px}.wrong-import-pair>div{grid-template-columns:1fr 1fr}.wrong-review-workspace{min-height:390px;grid-template-columns:1fr;grid-template-rows:150px 180px auto}.review-help-row{grid-column:1;grid-template-columns:repeat(3,1fr)}.review-help-row strong{grid-column:1 / -1}.similar-question-demo{min-height:340px;grid-template-rows:auto 22px 1fr}.similar-results-grid{grid-template-columns:1fr}.similar-results-grid article{min-height:64px;display:grid;grid-template-columns:54px 1fr auto;align-items:center;gap:8px}.similar-results-grid p{min-height:0;margin:0}.geometry-model-demo{min-height:390px;grid-template-columns:1fr;grid-template-rows:180px 1fr}.challenge-question-demo{min-height:370px;grid-template-columns:1fr;grid-template-rows:1fr auto}.challenge-section{grid-template-columns:46px repeat(8,minmax(0,1fr));gap:2px}.challenge-summary{min-height:92px}.poetry-writing-demo,.vocabulary-practice-demo{min-height:280px}.poetry-mode-tabs,.vocab-mode-tabs{grid-template-columns:repeat(2,1fr)}.trail-heatmap{grid-template-columns:repeat(7,13px);gap:5px}.trail-heatmap i{width:13px;height:13px}}@media(max-width:380px){.hero h1{font-size:36px}.section-heading h2,.closing h2{font-size:31px}.feature-card{flex-basis:86vw}.dialog-demo{padding:12px}}@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important}}
