:root{--primary:#4361ee;--primary-dark:#3a53cc;--bg:#f4f6fb;--surface:#fff;--text:#1e2433;--text-soft:#5c6577;--border:#e3e7f0;--success:#16a34a;--danger:#dc2626;--warning:#d97706;--radius:12px}*{box-sizing:border-box;margin:0;padding:0}body{background:var(--bg);color:var(--text);min-height:100vh;font-family:Segoe UI,system-ui,-apple-system,sans-serif}button{font-family:inherit}.btn{background:var(--primary);color:#fff;cursor:pointer;border:none;border-radius:8px;justify-content:center;align-items:center;gap:8px;padding:10px 20px;font-size:15px;font-weight:600;text-decoration:none;transition:background .15s;display:inline-flex}.btn:hover{background:var(--primary-dark)}.btn:disabled{cursor:not-allowed;background:#a5b0c8}.btn-danger{background:var(--danger)}.btn-danger:hover{background:#b91c1c}.btn-ghost{color:var(--text-soft);border:1px solid var(--border);background:0 0}.btn-ghost:hover{background:var(--bg)}.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:20px}.input{border:1px solid var(--border);background:var(--surface);width:100%;color:var(--text);border-radius:8px;padding:11px 14px;font-family:inherit;font-size:15px}.input:focus{outline:2px solid var(--primary);outline-offset:-1px;border-color:#0000}.badge{border-radius:999px;padding:3px 10px;font-size:12px;font-weight:700;display:inline-block}.badge-approved{color:var(--success);background:#dcfce7}.badge-pending{color:var(--warning);background:#fef3c7}.badge-rejected{color:var(--danger);background:#fee2e2}.error-text{color:var(--danger);font-size:14px}.login-wrap{justify-content:center;align-items:center;min-height:100vh;padding:16px;display:flex}.login-card{flex-direction:column;gap:14px;width:100%;max-width:400px;display:flex}.login-logo{text-align:center;margin-bottom:8px}.login-logo h1{color:var(--primary);letter-spacing:-.5px;font-size:26px}.login-logo p{color:var(--text-soft);margin-top:4px;font-size:14px}.topbar{background:var(--surface);border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;height:60px;padding:0 24px;display:flex}.topbar .brand{color:var(--primary);font-size:19px;font-weight:800;text-decoration:none}.topbar .user-area{color:var(--text-soft);align-items:center;gap:14px;font-size:14px;display:flex}.page{max-width:860px;margin:0 auto;padding:28px 16px}.page h2{margin-bottom:18px;font-size:21px}.lesson-list{flex-direction:column;gap:12px;display:flex}.lesson-card{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:12px;display:flex}.lesson-card .info{flex:1;min-width:220px}.lesson-card .title{font-size:16px;font-weight:700}.lesson-card .sub{color:var(--text-soft);margin-top:3px;font-size:14px}.empty-note{text-align:center;color:var(--text-soft);padding:40px 16px}.room{background:#0f1117;height:100vh;display:flex}.room.sidebar-collapsed .room-video{display:none}.room-warning{z-index:100;background:var(--warning);color:#1a1400;justify-content:center;align-items:center;gap:16px;padding:10px 16px;font-size:13px;font-weight:600;display:flex;position:fixed;top:0;left:0;right:0}.room-warning.danger{background:var(--danger);color:#fff}.room-warning button{color:inherit;cursor:pointer;background:#00000026;border:none;border-radius:6px;flex-shrink:0;padding:4px 12px;font-size:12px;font-weight:700}.room-video{flex-direction:column;gap:12px;width:340px;min-width:280px;padding:12px;display:flex}.video-box{background:#1a1e29;border-radius:10px;flex:1;min-width:0;min-height:140px;position:relative;overflow:hidden}.video-box .label{z-index:5;color:#fff;background:#00000073;border-radius:6px;padding:3px 9px;font-size:12px;font-weight:600;position:absolute;bottom:8px;left:10px}.video-box .placeholder{color:#5c6577;justify-content:center;align-items:center;font-size:14px;display:flex;position:absolute;inset:0}.video-el{width:100%;height:100%}.room-controls{justify-content:center;gap:10px;display:flex}.ctrl-btn{cursor:pointer;color:#fff;background:#ffffff1f;border:none;border-radius:50%;justify-content:center;align-items:center;width:46px;height:46px;font-size:19px;display:flex}.ctrl-btn.off,.ctrl-btn.leave{background:var(--danger)}.ctrl-btn.active{background:var(--primary)}.mic-error{color:#f87171;text-align:center;margin:0;font-size:12px}.mic-meter{background:#ffffff1f;border-radius:3px;height:5px;overflow:hidden}.mic-meter-fill{background:#22c55e;height:100%;transition:width .1s linear}.mic-select{color:#fff;background:#1a1e29;border:1px solid #ffffff26;border-radius:6px;width:100%;padding:5px 8px;font-size:12px}.room-board{flex:1;min-width:0;min-height:0;position:relative;overflow:hidden}.screen-share-box{background:#000;width:100%;height:100%;position:relative;overflow:hidden}.moderator-stop-share{z-index:6;background:var(--danger);color:#fff;cursor:pointer;border:none;border-radius:8px;padding:6px 14px;font-size:13px;font-weight:700;position:absolute;top:12px;right:12px;box-shadow:0 2px 8px #00000059}.screen-share-box video,.screen-share-box canvas{object-fit:contain;width:100%!important;height:100%!important}.room-board iframe{border:none;width:100%;height:100%}.sidebar-toggle{z-index:20;color:#fff;cursor:pointer;background:#ffffff26;border:none;border-radius:0 8px 8px 0;justify-content:center;align-items:center;width:20px;height:64px;font-size:13px;display:flex;position:absolute;top:50%;left:0;transform:translateY(-50%)}.sidebar-toggle:hover{background:#ffffff47}.floating-controls{z-index:15;gap:10px;display:flex;position:absolute;bottom:16px;left:50%;transform:translate(-50%)}.room-status{color:#8b93a5;text-align:center;font-size:13px}.room-timer{color:#4ade80;text-align:center;margin:0;font-size:13px;font-weight:700}.room-timer.over{color:#f87171}.room-timer-paused{color:#8b93a5;text-align:center;margin:2px 0 0;font-size:12px}@media (width<=800px){.room{flex-direction:column}.room-video{flex-direction:row;align-items:stretch;width:100%;height:170px}.video-box{flex:1}.room-controls{flex-direction:column;justify-content:center}.sidebar-toggle{border-radius:0 0 8px 8px;width:64px;height:18px;top:0;left:50%;transform:translate(-50%)}}.stream-tabs{flex-wrap:wrap;gap:8px;margin-bottom:20px;display:flex}.stream-grid{grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:18px;display:grid}.stream-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);cursor:pointer;transition:transform .15s,box-shadow .15s;overflow:hidden}.stream-card:hover{transform:translateY(-2px);box-shadow:0 6px 18px #1e243314}.stream-thumb{aspect-ratio:16/9;background:#1a1e29;position:relative}.stream-thumb img{object-fit:cover;width:100%;height:100%}.stream-thumb-placeholder{color:#fff;flex-direction:column;justify-content:center;align-items:center;gap:6px;width:100%;height:100%;display:flex}.stream-thumb-icon{font-size:28px}.stream-thumb-lesson{text-shadow:0 1px 3px #00000059;text-align:center;padding:0 10px;font-size:13px;font-weight:700}.stream-badge{color:#fff;border-radius:6px;padding:3px 9px;font-size:11px;font-weight:700;position:absolute;top:8px;left:8px}.stream-badge.live{background:var(--danger)}.stream-badge.upcoming{background:var(--warning)}.stream-badge.locked{background:#0000008c;left:auto;right:8px}.stream-badge.mine{background:#ef4444;top:auto;bottom:8px}.stream-info{padding:12px 14px}.stream-title{text-overflow:ellipsis;white-space:nowrap;font-size:14px;font-weight:700;overflow:hidden}.stream-sub{color:var(--text-soft);margin-top:3px;font-size:13px}.watch-layout{background:#0f1117;height:100vh;display:flex}.watch-video-col{flex-direction:column;flex:1;min-width:0;display:flex}.watch-video-box{aspect-ratio:16/9;background:#000;max-height:80vh;position:relative}.watch-video-el{width:100%;height:100%}.watch-live-badge{position:absolute;top:12px;left:12px}.watch-info{background:var(--surface);color:var(--text);padding:18px 24px;overflow-y:auto}.watch-paywall{background:#111;width:100%;height:100%;position:relative;overflow:hidden}.watch-paywall-bg{object-fit:cover;opacity:.35;filter:blur(2px);width:100%;height:100%;position:absolute;inset:0}.watch-paywall-overlay{z-index:1;text-align:center;color:#fff;flex-direction:column;justify-content:center;align-items:center;height:100%;padding:32px;display:flex;position:relative}.watch-paywall-icon{margin-bottom:14px;font-size:40px}.watch-paywall-overlay h3{margin-bottom:8px;font-size:20px}.watch-paywall-overlay p{color:#fff9;max-width:340px;font-size:14px}.watch-ended-overlay{z-index:5;text-align:center;color:#fff;background:#000000d1;flex-direction:column;justify-content:center;align-items:center;display:flex;position:absolute;inset:0}.watch-ended-icon{opacity:.8;margin-bottom:10px;font-size:36px}.watch-ended-overlay h3{font-size:19px;font-weight:700}.watch-chat-col{background:#171a23;border-left:1px solid #ffffff14;flex-direction:column;width:340px;min-width:280px;display:flex}.watch-chat-messages{flex:1;padding:14px;overflow-y:auto}.chat-msg{flex-direction:column;margin-bottom:10px;display:flex}.chat-msg.me{align-items:flex-end}.chat-author{color:#ffffff73;margin-bottom:2px;font-size:11px}.chat-bubble{color:#fff;background:#2a2f3d;border-radius:12px;max-width:85%;padding:7px 11px;font-size:13px;display:inline-block}.chat-msg.me .chat-bubble{background:var(--primary)}.watch-chat-input{border-top:1px solid #ffffff14;gap:8px;padding:12px;display:flex}.watch-chat-input .input{color:#fff;background:#20242f;border-color:#2f3547}@media (width<=900px){.watch-layout{flex-direction:column;height:auto;min-height:100vh}.watch-video-box{max-height:none}.watch-chat-col{width:100%;min-width:0;height:420px}}.landing{max-width:1080px;margin:0 auto;padding:0 24px 60px}.landing-topbar{justify-content:space-between;align-items:center;padding:24px 0;display:flex}.landing-logo{color:var(--primary);letter-spacing:-.5px;font-size:20px;font-weight:800}.landing-hero{text-align:center;padding:60px 0 50px}.landing-hero h1{letter-spacing:-1px;margin-bottom:18px;font-size:40px;line-height:1.2}.landing-hero p{color:var(--text-soft);max-width:560px;margin:0 auto;font-size:17px}.landing-features{grid-template-columns:repeat(4,1fr);gap:16px;margin-bottom:60px;display:grid}.landing-feature-card{text-align:center}.landing-feature-icon{margin-bottom:10px;font-size:30px}.landing-feature-card h3{margin-bottom:6px;font-size:16px}.landing-feature-card p{color:var(--text-soft);font-size:13px;line-height:1.5}.landing-subscription{grid-template-columns:1fr 1fr;gap:20px;margin-bottom:40px;display:grid}.landing-sub-card{text-align:center;padding:32px 24px}.landing-sub-card h2{margin-bottom:8px;font-size:20px}.landing-sub-price{color:var(--primary);margin-bottom:18px;font-weight:700}.landing-sub-list{text-align:left;color:var(--text-soft);flex-direction:column;gap:8px;margin:0 0 22px;font-size:14px;list-style:none;display:flex}.landing-footer{text-align:center;color:var(--text-soft);border-top:1px solid var(--border);padding-top:24px;font-size:13px}@media (width<=800px){.landing-hero h1{font-size:30px}.landing-features{grid-template-columns:repeat(2,1fr)}.landing-subscription{grid-template-columns:1fr}}.register-role-toggle{gap:8px;margin-bottom:4px;display:flex}.register-role-toggle .btn{flex:1}.content-filter-tabs{gap:8px;margin-bottom:18px;display:flex}.filter-chip{color:var(--text-soft);cursor:pointer;background:#eef0f6;border:none;border-radius:999px;padding:8px 16px;font-size:13px;font-weight:700}.filter-chip.active{background:var(--primary);color:#fff}.content-feed{flex-direction:column;gap:20px;display:flex}.content-card{background:var(--surface);border:1px solid var(--border);border-radius:16px;overflow:hidden;box-shadow:0 2px 10px #1e24330a}.content-media{aspect-ratio:4/5;background:#1a1e29;position:relative}.content-carousel{scroll-snap-type:x mandatory;scrollbar-width:none;height:100%;display:flex;overflow-x:auto}.content-carousel::-webkit-scrollbar{display:none}.content-slide{scroll-snap-align:start;flex:0 0 100%;height:100%;position:relative}.content-slide img,.content-slide video{object-fit:cover;width:100%;height:100%;display:block}.content-video-fallback{pointer-events:none;background:#3a3f4b;justify-content:center;align-items:center;font-size:32px;display:flex;position:absolute;inset:0}.content-broken-media{color:#b45309;text-align:center;background:#2a2620;justify-content:center;align-items:center;width:100%;height:100%;padding:16px;font-size:13px;font-weight:600;display:flex}.content-overlay-top{background:linear-gradient(#00000073,#0000);justify-content:space-between;align-items:center;padding:12px;display:flex;position:absolute;top:0;left:0;right:0}.content-author{align-items:center;gap:8px;display:flex}.content-author-name{color:#fff;text-shadow:0 1px 3px #0006;font-size:13px;font-weight:700}.content-author-sub{color:#fffc;font-size:11px;font-weight:600}.content-mute-btn{color:#fff;cursor:pointer;background:#0006;border:none;border-radius:50%;width:28px;height:28px;font-size:13px}.content-dots{justify-content:center;gap:4px;display:flex;position:absolute;top:10px;left:0;right:0}.content-dot{background:#ffffff73;border-radius:3px;width:5px;height:5px}.content-dot.active{background:#fff;width:14px}.content-overlay-bottom{background:linear-gradient(#0000,#000000bf);padding:30px 14px 12px;position:absolute;bottom:0;left:0;right:0}.content-title{color:#fff;-webkit-line-clamp:2;-webkit-box-orient:vertical;font-size:13px;font-weight:600;line-height:1.4;display:-webkit-box;overflow:hidden}.content-text-only{gap:10px;padding:14px 14px 4px;display:flex}.content-text-only .content-title{color:var(--text)}.content-avatar{background:#dfe3ee;border:1.5px solid #ffffffd9;border-radius:50%;justify-content:center;align-items:center;width:32px;min-width:32px;height:32px;display:flex;overflow:hidden}.content-avatar img{object-fit:cover;width:100%;height:100%}.content-actions{justify-content:space-between;align-items:center;padding:8px 10px;display:flex}.content-action-btn{cursor:pointer;color:var(--text-soft);background:0 0;border:none;border-radius:8px;align-items:center;gap:6px;padding:6px 8px;font-size:15px;font-weight:700;display:inline-flex}.content-action-btn:hover{background:var(--bg)}.content-action-btn.danger{color:var(--danger)}.content-fab{background:var(--primary);color:#fff;cursor:pointer;border:none;border-radius:50%;width:54px;height:54px;font-size:26px;line-height:1;position:fixed;bottom:24px;right:24px;box-shadow:0 6px 18px #4361ee66}.content-fab:hover{background:var(--primary-dark)}.content-media-preview-list{flex-wrap:wrap;gap:8px;display:flex}.content-media-preview-item{border-radius:8px;width:84px;height:84px;position:relative;overflow:hidden}.content-media-preview-item img,.content-media-preview-item video{object-fit:cover;width:100%;height:100%}.content-media-preview-item button{color:#fff;cursor:pointer;background:#dc2626e6;border:none;border-radius:50%;width:20px;height:20px;font-size:11px;position:absolute;top:3px;right:3px}.offer-filters{flex-wrap:wrap;gap:10px;margin-bottom:20px;display:flex}.offer-filters select{border:1px solid var(--border);background:var(--surface);color:var(--text);border-radius:8px;padding:10px 12px;font-size:14px}.offer-card-body{padding:14px}.offer-teacher{align-items:center;gap:10px;margin-bottom:10px;display:flex}.offer-avatar{object-fit:cover;border-radius:50%;flex-shrink:0;width:40px;height:40px}.offer-avatar-fallback{background:var(--bg);justify-content:center;align-items:center;font-size:18px;display:flex}.offer-desc{color:var(--text-soft);-webkit-line-clamp:2;-webkit-box-orient:vertical;margin-bottom:10px;font-size:13px;display:-webkit-box;overflow:hidden}.offer-meta{color:var(--text-soft);justify-content:space-between;align-items:center;font-size:13px;display:flex}.offer-price{color:var(--primary);font-weight:700}.quiz-progress{color:var(--text-soft);font-size:13px;font-weight:700}.quiz-timer{color:var(--danger);font-variant-numeric:tabular-nums;font-size:13px;font-weight:700}.quiz-option{text-align:left;border:2px solid var(--border);background:var(--surface);color:var(--text);cursor:pointer;border-radius:8px;padding:12px 16px;font-size:14px;transition:border-color .15s,background .15s}.quiz-option:hover{border-color:var(--primary)}.quiz-option.selected{border-color:var(--primary);background:#4361ee14;font-weight:600}.quiz-result-score h3{color:var(--primary)}.modal-overlay{z-index:50;background:#0f11178c;justify-content:center;align-items:center;padding:16px;display:flex;position:fixed;inset:0}.modal-box{background:var(--surface);border-radius:var(--radius);width:100%;max-width:440px;max-height:88vh;padding:22px;overflow-y:auto}.modal-box h3{margin-bottom:14px;font-size:18px}.modal-box textarea.input{resize:vertical;font-family:inherit}