:root{--bg:#0b0e14;--bg-elevated:#12161f;--bg-elevated-2:#171c28;--border:#232a3a;--border-strong:#303a50;--text:#e7eaf2;--text-dim:#9aa3b5;--text-faint:#6b7488;--accent:#f0b53d;--accent-strong:#ffc94d;--accent-dim:#3a3120;--success:#34d399;--danger:#f87171;--warning:#fbbf24;--info:#60a5fa;--radius:12px;--radius-sm:8px;--font:ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;--mono:ui-monospace, SFMono-Regular, Menlo, Consolas, monospace}*{box-sizing:border-box}html,body{margin:0;padding:0}body{background:var(--bg);color:var(--text);font-family:var(--font);-webkit-font-smoothing:antialiased;font-size:15px;line-height:1.55}a{color:inherit;text-decoration:none}button{font-family:inherit}.shell{flex-direction:column;min-height:100vh;display:flex}.nav{border-bottom:1px solid var(--border);z-index:20;background:#0b0e14e6;align-items:center;gap:20px;padding:14px 28px;display:flex;position:sticky;top:0}.nav-brand{letter-spacing:.3px;color:var(--text);align-items:center;gap:10px;font-size:17px;font-weight:700;display:flex}.nav-brand .mark{background:linear-gradient(135deg, var(--accent), #d98e1f);color:#1a1203;border-radius:7px;justify-content:center;align-items:center;width:26px;height:26px;font-size:14px;font-weight:800;display:inline-flex}.nav-links{flex:1;gap:4px;display:flex}.nav-link{border-radius:var(--radius-sm);color:var(--text-dim);padding:7px 12px;font-weight:500;transition:background .15s,color .15s}.nav-link:hover{background:var(--bg-elevated);color:var(--text)}.nav-link.active{color:var(--accent);background:#f0b53d14}.nav-user{color:var(--text-dim);align-items:center;gap:12px;font-size:14px;display:flex}.avatar{background:var(--bg-elevated-2);border:1px solid var(--border-strong);width:30px;height:30px;color:var(--accent);border-radius:50%;justify-content:center;align-items:center;font-size:13px;font-weight:600;display:inline-flex}.main{flex:1;width:100%;max-width:1060px;margin:0 auto;padding:34px 28px 60px}.page-title{letter-spacing:-.2px;margin:0 0 6px;font-size:24px;font-weight:700}.page-sub{color:var(--text-dim);margin:0 0 26px}.muted{color:var(--text-dim)}.small{font-size:13px}.badge{letter-spacing:.3px;border:1px solid var(--border-strong);color:var(--text-dim);background:var(--bg-elevated);white-space:nowrap;border-radius:999px;align-items:center;gap:6px;padding:3px 10px;font-size:12px;font-weight:600;display:inline-flex}.badge.ready{color:#0f3d2e;background:var(--success);border-color:#0000}.badge.processing{color:#3d2f07;background:var(--warning);border-color:#0000}.badge.failed{color:#fff;background:var(--danger);border-color:#0000}.badge.empty{color:var(--text-dim)}.badge.accent{color:#1a1203;background:var(--accent);border-color:#0000}.card{background:var(--bg-elevated);border:1px solid var(--border);border-radius:var(--radius);padding:22px 24px}.card+.card{margin-top:16px}.card-title{margin:0 0 4px;font-size:16px;font-weight:600}.grid{grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:16px;display:grid}.course-card{background:var(--bg-elevated);border:1px solid var(--border);border-radius:var(--radius);flex-direction:column;gap:10px;padding:20px;transition:border-color .15s,transform .15s;display:flex}.course-card:hover{border-color:var(--border-strong);transform:translateY(-1px)}.course-card h3{margin:0;font-size:16px;font-weight:600}.course-card .desc{color:var(--text-dim);-webkit-line-clamp:2;-webkit-box-orient:vertical;margin:0;font-size:13.5px;display:-webkit-box;overflow:hidden}.course-card .meta{color:var(--text-faint);justify-content:space-between;align-items:center;margin-top:2px;font-size:13px;display:flex}.progress-track{background:var(--bg-elevated-2);border:1px solid var(--border);border-radius:999px;height:6px;overflow:hidden}.progress-fill{background:linear-gradient(90deg, var(--accent), var(--accent-strong));border-radius:999px;height:100%;transition:width .3s}.progress-fill.done{background:var(--success)}.lesson-list{flex-direction:column;gap:10px;display:flex}.lesson-row{background:var(--bg-elevated);border:1px solid var(--border);border-radius:var(--radius);align-items:center;gap:16px;padding:14px 18px;transition:border-color .15s,background .15s;display:flex}.lesson-row:hover{border-color:var(--border-strong);background:var(--bg-elevated-2)}.lesson-row .idx{background:var(--bg-elevated-2);border:1px solid var(--border-strong);width:30px;height:30px;color:var(--text-dim);border-radius:50%;flex:0 0 30px;justify-content:center;align-items:center;font-size:13px;font-weight:600;display:inline-flex}.lesson-row .idx.done{background:var(--success);color:#0f3d2e;border-color:#0000}.lesson-row .body{flex:1;min-width:0}.lesson-row .title{margin:0;font-weight:600}.lesson-row .sub{color:var(--text-faint);margin:2px 0 0;font-size:12.5px}.lesson-row .right{align-items:center;gap:12px;display:flex}.btn{border-radius:var(--radius-sm);cursor:pointer;border:1px solid #0000;justify-content:center;align-items:center;gap:8px;padding:10px 18px;font-size:14px;font-weight:600;transition:background .15s,border-color .15s,color .15s,opacity .15s;display:inline-flex}.btn:disabled{opacity:.55;cursor:not-allowed}.btn-primary{background:var(--accent);color:#1a1203}.btn-primary:hover:not(:disabled){background:var(--accent-strong)}.btn-ghost{color:var(--text-dim);border-color:var(--border-strong);background:0 0}.btn-ghost:hover:not(:disabled){color:var(--text);border-color:#46536e}.btn-danger{color:var(--danger);background:#f871711f;border-color:#f8717159}.btn-danger:hover:not(:disabled){background:#f8717133}.btn-sm{padding:6px 12px;font-size:13px}.field{flex-direction:column;gap:6px;margin-bottom:16px;display:flex}.field label{color:var(--text-dim);font-size:13px;font-weight:600}.input,.select,textarea.input{background:var(--bg);border:1px solid var(--border-strong);border-radius:var(--radius-sm);color:var(--text);outline:none;width:100%;padding:10px 12px;font-family:inherit;font-size:14px;transition:border-color .15s}.input:focus,.select:focus{border-color:var(--accent)}.form-card{width:100%;max-width:420px;margin:40px 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video{background:#000;width:100%;height:100%;display:block}.player-overlay{pointer-events:none;flex-direction:column;justify-content:flex-end;display:flex;position:absolute;inset:0}.player-controls{pointer-events:auto;background:linear-gradient(#0000,#000000c7);flex-direction:column;gap:8px;padding:40px 16px 12px;display:flex}.player-buttons{color:#fff;align-items:center;gap:14px;display:flex}.player-buttons .spacer{flex:1}.pb-btn{color:#fff;cursor:pointer;opacity:.92;background:0 0;border:none;align-items:center;gap:6px;padding:4px;font-size:17px;display:inline-flex}.pb-btn:hover{opacity:1}.player-time{font-variant-numeric:tabular-nums;color:#ffffffd9;font-size:13px;font-family:var(--mono)}.seek{cursor:pointer;align-items:center;width:100%;height:18px;display:flex}.seek-track{background:#ffffff40;border-radius:999px;width:100%;height:5px;position:relative}.seek-track .fill{background:var(--accent);border-radius:999px;position:absolute;inset:0 auto 0 0}.seek-track .thumb{opacity:0;background:#fff;border-radius:50%;width:13px;height:13px;transition:opacity .15s;position:absolute;top:50%;transform:translate(-50%,-50%);box-shadow:0 1px 4px #00000080}.seek:hover .thumb{opacity:1}.big-play{cursor:pointer;background:0 0;border:none;justify-content:center;align-items:center;display:flex;position:absolute;inset:0}.big-play .circle{color:#fff;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);background:#0b0e14a6;border:1px solid #ffffff40;border-radius:50%;justify-content:center;align-items:center;width:74px;height:74px;font-size:26px;transition:transform .15s,background .15s;display:flex}.big-play:hover .circle{color:#1a1203;background:#f0b53dd9;transform:scale(1.06)}.player-playlist{flex-direction:column;gap:8px;max-height:560px;display:flex;overflow-y:auto}.pl-item{border-radius:var(--radius-sm);border:1px solid var(--border);background:var(--bg-elevated);cursor:pointer;text-align:left;align-items:center;gap:12px;width:100%;padding:12px 14px;font-size:14px;transition:border-color .15s,background .15s;display:flex}.pl-item:hover{border-color:var(--border-strong)}.pl-item.active{border-color:var(--accent);background:#f0b53d0f}.pl-item .pl-idx{background:var(--bg-elevated-2);border:1px solid var(--border-strong);width:26px;height:26px;color:var(--text-dim);border-radius:50%;flex:0 0 26px;justify-content:center;align-items:center;font-size:12px;font-weight:600;display:inline-flex}.pl-item .pl-idx.done{background:var(--success);color:#0f3d2e;border-color:#0000}.pl-item .pl-body{flex:1;min-width:0}.pl-item .pl-title{white-space:nowrap;text-overflow:ellipsis;margin:0;font-size:13.5px;font-weight:600;overflow:hidden}.pl-item .pl-sub{color:var(--text-faint);margin:1px 0 0;font-size:12px}.player-placeholder{color:var(--text-dim);text-align:center;flex-direction:column;justify-content:center;align-items:center;gap:10px;padding:60px 24px;display:flex}.status-table{border-collapse:collapse;width:100%;font-size:13.5px}.status-table th{text-align:left;color:var(--text-faint);text-transform:uppercase;letter-spacing:.5px;border-bottom:1px solid var(--border);padding:8px 10px;font-size:12px;font-weight:600}.status-table td{border-bottom:1px solid var(--border);vertical-align:middle;padding:10px}.status-table tr:last-child td{border-bottom:none}.mono{font-family:var(--mono);font-size:12.5px}.error-text{color:var(--danger)}.row{align-items:center;gap:12px;display:flex}.row-between{justify-content:space-between;align-items:center;gap:12px;display:flex}.stack{flex-direction:column;gap:10px;display:flex}.mt-4{margin-top:4px}.mt-8{margin-top:8px}.mt-16{margin-top:16px}.mt-24{margin-top:24px}.notice{color:var(--info);border-radius:var(--radius-sm);background:#60a5fa14;border:1px solid #60a5fa4d;padding:10px 14px;font-size:13.5px}.kbd{font-family:var(--mono);background:var(--bg-elevated-2);border:1px solid var(--border-strong);border-radius:4px;padding:1px 6px;font-size:12px}hr{border:none;border-top:1px solid var(--border);margin:20px 0}