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@media(max-width:960px){.intro-shell{margin:0 28px;gap:28px}.learning-shell{grid-template-columns:205px minmax(0,1fr);gap:20px;padding:22px}#learning-main{padding:26px}.course-header{padding:16px 22px}}
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@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;animation:none!important;transition:none!important}}

.course-header:not(:has(button))>span{max-width:none}.dialog-head{position:sticky;top:0;background:white;z-index:1;padding-bottom:8px}
.course-map-entry{display:inline-flex;align-items:center;min-height:44px;font-size:14px;margin-left:18px}.lesson-map{margin:20px 0;border-top:1px solid var(--line);padding-top:15px}.lesson-map h2{font-size:16px}.lesson-map button{display:block;width:100%;text-align:left;margin:8px 0}.lesson-map button small{display:block;margin-top:4px}.unit-map-link{display:inline-block;margin-bottom:16px;font-size:14px}@media(max-width:760px){.course-header .course-map-entry{margin-left:auto;font-size:12px}.course-header>span{display:none}.start-area .course-map-entry{margin-left:0}}

/* 2026-09-07 course hierarchy: course modules, unit path, lesson task. */
.intro-shell{padding-top:34px;grid-template-columns:minmax(0,1.05fr) minmax(420px,.95fr);gap:46px}
.course-intro{padding:24px 4px}.course-outcomes{max-width:620px}.start-area{display:flex;align-items:center;gap:16px;flex-wrap:wrap}.start-area p{margin:0;max-width:360px}
.course-overview{padding:22px;background:#fff}.overview-head h2{margin-bottom:12px}.module-route{display:grid;gap:10px;margin:0}.module-route .module-card{display:grid;grid-template-columns:42px minmax(0,1fr) auto;align-items:center;gap:13px;padding:15px;border:1px solid var(--line);border-left:4px solid var(--green);border-radius:11px;background:#fff}.module-route .module-card+.module-card{margin-top:0}.module-route .module-card>span{color:inherit}.module-card-number{display:grid;place-items:center;width:38px;height:38px;border-radius:9px;background:var(--soft);font-weight:750;font-size:13px}.module-route .module-card small{display:block;margin-bottom:1px}.module-route .module-card h3{font-size:18px;margin:0}.module-route .module-card p{margin:2px 0 0}.module-route .module-card>a{padding:7px 10px;border:1px solid currentColor;border-radius:8px;text-decoration:none;font-size:13px}.module-route .module-two-card{border-left-color:#2f668d;color:#244f6c}.module-route .module-two-card .module-card-number{background:#edf3f7}.module-route .module-three-card{border-left-color:#a95d2c;color:#724521}.module-route .module-three-card .module-card-number{background:#f8eee7}.module-route .module-three-card p,.module-route .module-three-card small{color:#776b62}
.course-spaces{grid-column:1/-1;display:grid;grid-template-columns:1fr 1fr;gap:14px}.course-spaces article{display:flex;justify-content:space-between;align-items:center;gap:24px;padding:18px 20px;background:#fff;border:1px solid var(--line);border-radius:12px}.course-spaces h2{margin:0 0 3px}.course-spaces p{margin:0;color:var(--muted);font-size:14px}.course-spaces .eyebrow{margin-bottom:2px;font-size:11px}.course-spaces a,.course-spaces button{flex:0 0 auto;min-height:42px;padding:8px 12px;border:1px solid var(--line);border-radius:8px;color:var(--green);background:#fff;text-decoration:none;font-weight:650}.course-spaces .assistant-space{border-color:#cadfce;background:#f3f7f3}.course-spaces .assistant-space button{color:#fff;background:var(--green);border-color:var(--green)}

.module-page-identity{max-width:1180px;margin:0 auto;padding:20px 28px 0;display:flex;justify-content:space-between;align-items:end;gap:20px}.module-page-identity .eyebrow{margin-bottom:3px}.module-page-identity h1{margin:0;font-size:25px}.module-page-identity p:last-child{margin:0;color:var(--muted);font-size:14px}
.learning-shell{padding-top:20px;grid-template-columns:230px minmax(0,1fr);gap:24px}.course-directory{padding-right:8px}.course-directory>a{display:none}.course-directory h2{margin:0 0 12px;font-size:17px}.unit-path{display:grid;gap:8px}.unit-path-card{border:1px solid var(--line);border-radius:10px;background:#fff;overflow:hidden}.unit-path-card.is-current{border-color:#b8d0be}.unit-path-heading{width:100%;display:grid;grid-template-columns:29px minmax(0,1fr) auto;align-items:center;gap:8px;min-height:48px;padding:8px 9px;border:0;border-radius:0;text-align:left;background:transparent}.unit-path-heading:hover{background:var(--soft)}.unit-index{display:grid;place-items:center;width:27px;height:27px;border-radius:7px;background:var(--soft);color:var(--green);font-size:11px;font-weight:750}.unit-path-heading strong{font-size:13px}.unit-path-heading small{font-size:11px}.unit-lesson-list{display:grid;gap:2px;padding:0 7px 7px 44px}.unit-lesson-list .directory-node{min-height:36px;padding:6px 8px}.unit-lesson-list .directory-node span{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.course-progress{margin:13px 2px 0}.course-progress-track{height:6px;overflow:hidden;border-radius:99px;background:#e5ebe6}.course-progress-track span{display:block;height:100%;background:var(--green)}
#learning-main{padding:26px 30px}.lesson-context{display:flex;align-items:center;gap:9px;margin-bottom:17px;color:var(--muted);font-size:13px}.lesson-context .module-tag{padding:3px 8px;border-radius:6px;background:var(--soft);color:var(--green);font-weight:700}.lesson-media{margin:22px 0 24px}.lesson-media-head{display:flex;align-items:end;justify-content:space-between;gap:18px;margin-bottom:10px}.lesson-media-head h2{margin:2px 0 0;font-size:18px}.video-kicker{color:var(--green);font-size:11px;font-weight:750;letter-spacing:.08em}.video-duration{flex:0 0 auto;padding:4px 9px;border:1px solid var(--line);border-radius:999px;color:var(--muted);font-size:12px}.lesson-video{position:relative;margin:0;border:1px solid #173c2a;border-radius:13px;overflow:hidden;background:#102d20;aspect-ratio:16/9}.lesson-video video{display:block;width:100%;height:100%;object-fit:contain;background:#0c1711}.lesson-video figcaption{position:absolute;left:0;right:0;bottom:0;padding:9px 13px;color:#e2ece5;background:rgba(11,31,21,.88);font-size:12px}.lesson-video-visual{position:absolute;inset:0;overflow:hidden;background:radial-gradient(circle at 66% 44%,rgba(117,180,139,.22),transparent 0 24%,transparent 48%),linear-gradient(135deg,#0c2419 0%,#183e2c 54%,#102b1e 100%)}.lesson-video-visual::before{content:"";position:absolute;inset:10%;background:linear-gradient(rgba(159,198,172,.09) 1px,transparent 1px),linear-gradient(90deg,rgba(159,198,172,.09) 1px,transparent 1px);background-size:34px 34px;mask-image:linear-gradient(90deg,transparent,#000 22% 78%,transparent)}.video-orbit{position:absolute;left:63%;top:50%;width:56%;aspect-ratio:1;border:1px solid rgba(178,218,191,.38);border-radius:50%;transform:translate(-50%,-50%)}.orbit-two{width:34%;border-color:rgba(178,218,191,.55)}.video-pulse{position:absolute;left:63%;top:50%;display:grid;place-items:center;width:68px;height:68px;border-radius:50%;background:#f3f8f4;box-shadow:0 16px 40px rgba(0,0,0,.28);transform:translate(-50%,-50%)}.video-pulse i{display:block;width:0;height:0;margin-left:5px;border-top:10px solid transparent;border-bottom:10px solid transparent;border-left:16px solid #245f3d}.video-wordmark{position:absolute;left:7%;bottom:10%;color:rgba(235,245,238,.78);font-size:clamp(13px,2.1vw,23px);font-weight:720;line-height:1.12;letter-spacing:.12em}.video-focus{display:grid;grid-template-columns:76px minmax(0,1fr);gap:12px;margin:11px 2px 0;color:var(--muted);font-size:13px;line-height:1.6}.video-focus strong{color:var(--ink)}.lesson-tools{align-items:center}.lesson-tools::before{content:"本课支持";margin-right:5px;color:var(--muted);font-size:12px}.lesson-tools button[data-tool="ask"]{color:var(--green);border-color:#bdd3c3;background:#f2f7f3;font-weight:700}

/* Grouped learning points: concise course layer over the detailed graph. */
.unit-guide{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:24px 0}.unit-guide>div{padding:18px;border:1px solid var(--line);border-radius:11px;background:#fbfcfa}.unit-guide h2,.unit-route h2,.concept-cluster h2,.lesson-sections h2,.learning-summary h2,.completion-card h2{font-size:16px;margin-bottom:9px}.unit-guide ul,.learning-summary ul{margin:0;padding-left:20px}.unit-guide li,.learning-summary li{margin:5px 0}.unit-route{margin:26px 0}.unit-route>button{width:100%;display:grid;grid-template-columns:32px minmax(130px,.45fr) minmax(0,1fr);align-items:center;gap:12px;text-align:left;margin:8px 0;padding:12px 14px}.unit-route>button>span{display:grid;place-items:center;width:29px;height:29px;border-radius:8px;background:var(--soft);color:var(--green);font-size:12px;font-weight:750}.unit-route>button small{line-height:1.5}.point-overview{margin:0 0 20px;padding:16px 19px 18px;border-left:4px solid var(--green);background:var(--soft)}.point-overview strong{display:block;margin-bottom:6px;color:var(--green);font-size:13px;letter-spacing:.04em}.point-overview p{margin:0;font-size:16px;line-height:1.85}.concept-cluster{margin:18px 0}.concept-cluster>div{display:flex;flex-wrap:wrap;gap:8px}.concept-cluster button{min-height:36px;padding:6px 11px;border-radius:999px;color:var(--green);background:#fff;font-size:13px}.lesson-sections{display:grid;gap:11px;margin:22px 0}.lesson-sections section{padding:17px 18px;border:1px solid var(--line);border-radius:10px}.lesson-sections p{margin:0}.learning-summary{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:22px 0}.learning-summary>div{padding:17px 18px;border-radius:10px;background:#f5f8f4}.learning-summary .mistake{background:#faf4ec}.learning-summary p{margin:0}.design-connection{display:grid;grid-template-columns:88px minmax(0,1fr);gap:10px;padding:16px 18px;border:1px solid #c9d9cd;border-radius:10px;margin:20px 0}.design-connection strong{color:var(--green)}.check-intro{color:var(--muted)}.check-set{display:grid;gap:20px}.check-set .micro-options{padding:18px;border:1px solid var(--line);border-radius:11px;margin:0}.micro-options legend{width:100%;padding:0 3px}.micro-options legend>span{display:inline-grid;place-items:center;width:27px;height:27px;margin-right:8px;border-radius:7px;background:var(--soft);color:var(--green);font-size:12px;vertical-align:middle}.answer-results{display:grid;gap:10px;margin:18px 0}.answer-result{padding:14px 16px;border-left:3px solid var(--green);background:var(--soft)}.answer-result.incorrect{border-color:var(--amber);background:#faf4ec}.answer-result h3{margin:0 0 6px}.answer-result p{margin:5px 0}.completion-card{margin-top:20px;padding:18px;border:1px solid var(--line);border-radius:10px}.completion-card p{margin:0}.textbook-source ul{margin:10px 0 0;padding-left:20px}.textbook-source li{margin:6px 0}

@media(max-width:960px){.intro-shell{grid-template-columns:1fr 1fr;margin:0 24px}.module-page-identity{padding:18px 22px 0}.learning-shell{grid-template-columns:210px minmax(0,1fr)}}
@media(max-width:760px){.intro-shell{margin:0;padding:22px 16px}.course-intro{padding:5px 0}.course-overview{margin-top:24px}.course-spaces{grid-template-columns:1fr;margin-top:14px}.course-spaces article{align-items:flex-start}.module-page-identity{padding:16px 16px 0}.module-page-identity h1{font-size:22px}.module-page-identity p:last-child{display:none}.learning-shell{padding-top:12px}.course-directory{padding:14px}.course-directory h2{margin-bottom:10px}#learning-main{padding:20px 17px}.lesson-tools::before{width:100%}.lesson-tools{justify-content:flex-start}.lesson-tools button{font-size:13px;padding:8px 10px}.start-area{display:block}.start-area p{margin-top:10px}.module-route .module-card{grid-template-columns:38px minmax(0,1fr) auto;padding:12px}.module-route .module-card p{font-size:12px}.course-assistant-fab{bottom:12px}.unit-guide,.learning-summary{grid-template-columns:1fr}.unit-route>button{grid-template-columns:30px minmax(0,1fr)}.unit-route>button small{grid-column:2}.lesson-context{flex-wrap:wrap}.lesson-media{margin-top:20px}.lesson-media-head{align-items:center}.lesson-media-head h2{font-size:16px}.lesson-video{border-radius:10px}.video-pulse{width:54px;height:54px}.video-orbit{width:68%}.orbit-two{width:42%}.video-focus{grid-template-columns:1fr;gap:2px;margin-top:9px}.design-connection{grid-template-columns:1fr}.check-set .micro-options{padding:14px}.micro-options legend{font-size:16px}.concept-cluster button{min-height:40px}}

/* Unit guide makes the shared guide → video lesson structure explicit. */
.unit-route-head{display:flex;align-items:center;justify-content:space-between;gap:18px;margin-bottom:8px}.unit-route-head h2{margin:0}.unit-route-head span{color:var(--muted);font-size:12px}.unit-route>button{grid-template-columns:32px minmax(130px,.42fr) minmax(0,1fr) auto}.unit-route-video{padding:4px 8px;border-radius:999px;background:var(--soft);color:var(--green);font-size:11px;font-style:normal;font-weight:700;white-space:nowrap}
@media(max-width:760px){.unit-route-head{align-items:flex-start;flex-direction:column;gap:2px}.unit-route>button{grid-template-columns:30px minmax(0,1fr) auto}.unit-route>button strong{grid-column:2}.unit-route>button small{grid-column:2/4}.unit-route-video{grid-column:3;grid-row:1}}