/* Navigation and content hierarchy */
body.player-focus .sidebar,body.player-focus .course-heading,body.player-focus .resource-panel,body.player-focus footer,body.player-focus .lesson-note,body.player-focus .related-content,body.player-focus .text-details{display:none}body.player-focus .workspace{margin-left:0}body.player-focus .learning-layout{display:block}body.player-focus main{max-width:1200px;padding-top:14px}body.player-focus .lesson-heading{padding-block:12px}body.player-focus .player-shell{max-width:calc((100dvh - 260px) * var(--stage-ratio,1.375));margin-inline:auto}body.player-focus .player-toolbar{max-width:1000px;margin-inline:auto;padding-inline:20px}body.player-focus .lesson-navigation{padding-block:10px}@media(max-width:780px){body.player-focus .player-shell{max-width:none}.player-toolbar{flex-wrap:wrap}.player-toolbar>div{display:flex;flex-wrap:wrap}}
.course-heading>div:first-child{min-width:0}.system-title-suffix{display:block;font-size:21px;font-weight:500;letter-spacing:2px;margin-top:4px}.brand>span:last-child{white-space:nowrap}.course-heading h1{letter-spacing:0}.course-heading .course-stats{flex-shrink:0}
.sidebar{width:238px;padding:27px 14px 16px}.workspace{margin-left:238px}.brand{padding:0 9px 27px;font-size:18px}.brand small{letter-spacing:.4px}#chapters button{padding:9px 10px;font-size:12px;line-height:1.65;align-items:center;gap:8px}.chapter-num{min-width:20px}.chapter-count{color:#93a292;font-size:10px}.chapter-stage{margin-top:14px}.stage-label{font-size:10px;letter-spacing:.7px;color:#94a18f;padding:4px 12px 8px}.side-label{padding-bottom:9px}.course-heading{margin-bottom:24px}main{padding-top:28px}.course-heading p{font-size:12px}.learning-layout{grid-template-columns:330px minmax(0,1fr);gap:22px}.resource-panel{padding:22px 18px 0}.panel-kicker{font-size:10px;letter-spacing:1px;color:#93a18b;margin-bottom:6px}.list-heading{align-items:flex-start;margin-bottom:18px}.list-heading h2{font-size:16px;line-height:1.6;max-width:245px}.list-heading>span{padding-top:5px}.search-box{padding:9px 11px;border-radius:8px}.search-box input{font-size:12px;line-height:22px}.search-box button{border:0;background:none;color:#8a9d83;padding:0 2px;font-size:18px}.mode-tabs{display:flex;border-bottom:1px solid #e5ece2;gap:17px;margin-top:17px;padding:0 3px}.mode-tabs button{position:relative;border:0;background:none;font-size:12px;padding:0 1px 13px;color:#8c9a83;white-space:nowrap}.mode-tabs button.active{color:#2a6b4c;font-weight:600}.mode-tabs button.active::after{content:"";position:absolute;bottom:-1px;left:0;right:0;height:2px;border-radius:2px;background:#428561}.tab-count{font-size:10px;opacity:.7;padding-left:2px}.mode-tabs [data-mode="reference"]{margin-left:auto;font-weight:400;font-size:11px}.mode-tabs [data-mode="reference"] .tab-count{display:none}.resource-list{min-height:0;max-height:min(65vh,720px);padding:13px 0 15px}.resource{padding:13px 10px;gap:11px;margin:2px 0;align-items:center;min-height:56px;border-radius:8px}.resource-badge{min-width:36px;flex-shrink:0;font-size:11px;font-variant-numeric:tabular-nums;text-align:center;line-height:29px;color:#8a9b80;border:1px solid #e4ebdf;border-radius:6px;background:#f9fbf5}.resource-body{min-width:0;flex:1}.resource-title{font-size:12px;line-height:1.8;-webkit-line-clamp:2;color:#52634a}.resource-arrow{font-size:15px;color:#afbaa5;flex-shrink:0}.resource.selected .resource-arrow{font-size:9px;color:#58815c}.resource.selected .resource-badge{background:white;color:#2b7251;border-color:#c7dcc6}.resource.selected{background:#eff6ed;border-color:#d4e4ce}.resource-meta{font-size:10px;line-height:1.7;margin-top:4px;color:#8f9d83}.resource-snippet{font-size:10px;color:#7f8f73}.list-tip{padding:13px 0 15px;font-size:10px;color:#9aa58f}.list-section-title{font-size:11px;line-height:1.8;font-weight:500;color:#859779;margin:18px 8px 7px}.list-section-title:first-child{margin-top:3px}.learning-route{margin-top:24px;padding-top:18px;border-top:1px solid #e8eee1}.route-heading{margin:0 8px 12px;font-size:11px;font-weight:500;color:#96a18a}.route-step{display:flex;align-items:center;width:100%;border:0;border-radius:6px;background:none;padding:10px 8px;gap:11px;text-align:left;font-size:11px;color:#677c58}.route-step:hover{background:#f5f8f0}.route-range{min-width:49px;font-size:10px;color:#a0ae94}.route-arrow{margin-left:auto;color:#91a781}.empty{font-size:12px;padding:20px 9px;line-height:2}.empty-action,.show-more{display:block;width:100%;border:1px solid #dce8d1;background:#f6faf1;color:#5f7f4d;border-radius:6px;padding:10px;font-size:11px;margin:8px 0}.section-note{font-size:11px;line-height:1.9;color:#8d9e80;margin:3px 6px 14px}.archive-group{border:1px solid #e5ecde;border-radius:8px;margin:9px 0;overflow:hidden}.archive-group summary{cursor:pointer;display:flex;align-items:center;justify-content:space-between;font-size:12px;color:#677d56;padding:13px 12px;background:#fafcf7;list-style:none}.archive-group summary::before{content:"▸";font-size:10px;color:#a1b293;margin-right:9px}.archive-group summary>span:first-child{flex:1}.archive-group[open]>summary::before{content:"▾"}.archive-count{font-size:10px;color:#9cae8c}.archive-group .resource{border-radius:0;margin:0;border-top:1px solid #eff3e9;padding:11px 10px}.archive-group .resource-badge{font-size:12px;min-width:25px;border:0;background:none}.archive-group .resource-title{font-size:11px}.question-ranges{display:flex;gap:6px;margin:2px 0 13px}.question-ranges button{font-size:10px;flex:1;border:1px solid #e6eddc;background:#fafcf6;color:#94a57e;padding:7px 4px;border-radius:5px}.question-ranges button.active{background:#eef5e7;border-color:#d3e1c5;color:#68874a}.question-picker{display:grid;grid-template-columns:repeat(5,1fr);gap:7px;padding:2px 1px 16px}.question-picker button{font-size:11px;font-variant-numeric:tabular-nums;border:1px solid #e4ebdb;color:#7b915e;background:#fff;border-radius:6px;min-height:33px;padding:7px 1px}.question-picker button:hover{background:#f4f8ee}.question-picker button.active{background:#477b4c;border-color:#477b4c;color:#fff;font-weight:600}.question-detail{border-top:1px solid #e6eddc;padding-top:16px}.question-heading{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:0 5px 8px}.question-heading h3{font-size:13px;margin:0;font-weight:600;color:#547543}.question-heading>span{font-size:10px;color:#9aac89}.question-prompt{font-size:11px;line-height:1.9;color:#859a70;margin:4px 6px 13px;max-height:6em;overflow:auto}.question-detail .resource-badge{min-width:29px;font-size:13px}.exercise-chapter{display:block;border:1px solid #e5ecdd;border-radius:6px;background:white;text-align:left;color:#6d8455;line-height:1.9;font-size:11px;width:100%;padding:11px;margin-bottom:7px}.search-scopes{display:flex;gap:6px;margin:0 0 13px;position:sticky;top:-14px;background:white;z-index:1;padding:8px 0}.search-scopes button{border:0;background:#f6f9f1;color:#91a27c;font-size:10px;border-radius:5px;flex:1;padding:8px 4px}.search-scopes button.active{background:#e9f2dd;color:#5f7f40;font-weight:600}.lesson-heading h2{font-size:21px;line-height:1.7}.lesson-description{font-size:12px;color:#869774;line-height:1.9;margin:-9px 25px 19px}.lesson-heading{padding-bottom:19px}.related-content{padding:7px 23px 4px}.related-group{background:#f8fbf2;border:1px solid #e8efdb;border-radius:7px;padding:10px 12px}.related-group summary{cursor:pointer;color:#779257;font-size:11px}.related-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:8px;margin-top:12px}.related-grid button,.return-course{font-size:11px;color:#70934d;background:white;border:1px solid #dfeacf;border-radius:6px;line-height:1.8;padding:7px;text-align:left}.return-course{padding:7px 12px}.lesson-note p{font-size:11px}.lesson-navigation{padding-top:16px}.lesson-navigation button{font-size:11px}.lesson-meta{font-size:10px;line-height:1.8}
@media(max-width:1280px){.learning-layout{grid-template-columns:290px minmax(0,1fr);gap:18px}.resource-panel{padding-inline:15px}.list-heading h2{font-size:15px}.resource-arrow{display:none}.lesson-heading h2{font-size:19px}.sidebar{width:220px}.workspace{margin-left:220px}.brand{font-size:16px;gap:9px}.topbar{padding-inline:24px}}
@media(max-width:1050px){.sidebar{width:205px}.workspace{margin-left:205px}.learning-layout{grid-template-columns:260px minmax(0,1fr);gap:15px}.resource-panel{padding-inline:12px}.mode-tabs{gap:12px}.brand{padding-inline:3px}.resource{padding-inline:7px;gap:8px}.resource-badge{min-width:31px;font-size:10px}.resource-title{font-size:11px}.question-picker{gap:5px}.question-picker button{font-size:10px}.list-heading h2{font-size:14px}.course-heading{margin-bottom:20px}.lesson-heading h2{font-size:17px}}
@media(max-width:780px){.sidebar{width:252px}.workspace{margin-left:0}.learning-layout{grid-template-columns:1fr}.resource-panel{padding:18px 16px 0}.list-heading{margin-bottom:13px}.list-heading h2{font-size:16px;max-width:none}.resource-title{font-size:12px}.resource-arrow{display:inline}.resource-badge{min-width:36px;font-size:11px}.resource-list{max-height:390px;padding-block:10px}.mode-tabs{gap:20px;margin-top:14px}.list-tip{padding:10px 0}.learning-route{margin-top:16px;padding-top:13px}.route-step{padding:9px 7px}.question-picker{grid-template-columns:repeat(5,1fr);gap:7px}.question-picker button{font-size:11px}.lesson-heading h2{font-size:19px}.lesson-description{margin-inline:17px}.related-content{padding-inline:16px}.course-heading{margin-bottom:20px}.resource-list:has(.learning-route){max-height:none}}