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.compare-card{padding:18px;margin-top:12px;border:1px solid var(--line);border-left:4px solid var(--purple);border-radius:11px;background:#fff}.compare-card h3{margin:8px 0 12px}.comparison-content{white-space:pre-wrap;font-size:14px;line-height:1.55}
.filters{display:flex;gap:10px;align-items:center;flex-wrap:wrap;margin-bottom:18px}.filters select{border:1px solid var(--line);border-radius:8px;padding:10px;background:#fff;color:var(--ink);font:inherit;min-width:210px}
.teacher-question-form{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:12px;align-items:end}.teacher-question-form textarea{width:100%;min-height:112px;resize:vertical;border:1px solid var(--line);border-radius:12px;padding:13px 14px;background:var(--bg);color:var(--ink);font:inherit;line-height:1.5;outline:none}.teacher-question-form textarea:focus{border-color:var(--blue);box-shadow:0 0 0 3px var(--blue-soft)}.question-list{display:grid;gap:12px}.question-card{padding:16px;border:1px solid var(--line);border-left:4px solid var(--purple);border-radius:12px;background:var(--bg)}.question-card strong{display:block;white-space:pre-wrap;font-weight:650}.question-meta{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-top:12px;color:var(--muted);font-size:12px}.question-meta button{border:0;background:var(--green-soft);color:var(--green);border-radius:99px;padding:7px 10px;font-weight:700;cursor:pointer}
.video-group{margin-top:18px}.video-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.video-card{border:1px solid var(--line);border-radius:13px;background:var(--bg);padding:14px}.video-card h3{font-size:15px;line-height:1.35;margin:10px 0 12px}.video-card video{display:block;width:100%;border-radius:9px;background:#000;aspect-ratio:16/9}.video-badge{font-size:11px;font-weight:800;letter-spacing:.08em;color:var(--blue)}.video-card .download-button{display:inline-block;margin-top:12px}@media(max-width:750px){.video-grid{grid-template-columns:1fr}}
.source-row{padding:13px 0;border-bottom:1px solid var(--line);font-size:14px}.source-row strong{display:block;color:var(--blue);font-size:12px;margin-bottom:4px}.official-link{display:inline-block;background:var(--blue);color:#fff;text-decoration:none;border-radius:8px;padding:10px 13px;font-weight:700}
.replay-link{color:var(--blue);font-weight:700;text-decoration:none}.replay-link:hover{text-decoration:underline}
.document-group{margin-top:24px}.document-group:first-of-type{margin-top:20px}.document-row{display:flex;align-items:center;gap:13px;padding:14px 0;border-top:1px solid var(--line)}.document-icon{width:42px;height:42px;border-radius:11px;background:var(--blue-soft);color:var(--blue);display:grid;place-items:center;font-size:10px;font-weight:800;flex-shrink:0}.document-info{min-width:0;flex:1}.document-info strong,.document-info small{display:block}.document-info strong{font-size:14px}.document-info small{color:var(--muted);font-size:12px;margin-top:3px}.download-button{background:var(--blue);color:#fff;text-decoration:none;border-radius:8px;padding:9px 12px;font-size:13px;font-weight:700;white-space:nowrap}.download-button:hover{filter:brightness(1.08)}
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body.dark-mode .search input{color:var(--ink)}
 .auth-gate{background:#f5f7fa}