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var(--c-border);border-radius:999px;font-weight:600}.checkbox{flex-direction:row;align-items:center;gap:8px}.result{margin-top:14px;background:linear-gradient(135deg,#2a3544,#1e293b);color:#dbeafe;border-radius:var(--radius-sm);padding:14px;font-size:13px;white-space:pre-wrap}.empty{margin:8px 0 0;color:var(--c-text-muted);text-align:center;padding:24px}.pass-student-list{margin:0;padding:0;list-style:none}.pass-student-list li{padding:8px 12px;border-bottom:1px solid var(--c-border);font-size:13px}.pass-student-list li.pass-ok{color:var(--c-success)}.pass-student-list li.pass-fail{color:var(--c-danger)}.student-list-block{margin-top:28px}@media (max-width: 960px){.assignment-row.student-row{grid-template-columns:48px minmax(0,1fr) auto;grid-template-areas:"id title actions" "id preview actions" "id meta actions"}}@media (max-width: 900px){.workspace{grid-template-columns:1fr}.sidebar{position:static}.form-grid,.two-cols,.detail-grid{grid-template-columns:1fr}.topbar{flex-direction:column;align-items:flex-start}.topbar-actions{width:100%;flex-wrap:wrap;justify-content:space-between}h1{font-size:26px}}.file-hint{margin:8px 0 0;font-size:13px;color:#5a6f85}.file-hint.muted{color:#a8bdd4}.video-filter{margin-top:24px;margin-bottom:16px}.button.danger{color:var(--c-danger);border:2px solid #ffd4d4;background:#fff5f5}.button.danger:hover{background:#fff0f0}.app-shell.is-student{padding:12px 14px 28px}.workspace--student{grid-template-columns:1fr}.student-video-toolbar{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:14px;flex-wrap:wrap}.student-grade-chip{display:inline-flex;align-items:center;padding:6px 12px;border-radius:999px;background:var(--c-primary-soft);color:var(--c-primary-dark);font-size:13px;font-weight:600}.video-type-tabs--student{display:grid;grid-template-columns:1fr 1fr;gap:8px}.video-type-tabs--student .video-type-tab{width:100%;justify-content:center;text-align:center}.student-video-list{display:flex;flex-direction:column;gap:10px}.student-video-item{display:flex;align-items:center;gap:12px;padding:14px 12px;border:2px solid var(--c-border);border-radius:var(--radius-md);background:#fbfdff;text-decoration:none;color:inherit;transition:border-color .15s ease,box-shadow .15s ease}.student-video-item:active,.student-video-item:hover{border-color:var(--c-primary);box-shadow:var(--shadow-sm)}.student-video-play{flex-shrink:0;width:44px;height:44px;border-radius:50%;display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#6ec0ff,var(--c-primary-dark));color:#fff;font-size:14px;padding-left:2px}.student-video-body{flex:1;min-width:0}.student-video-title{font-size:15px;font-weight:700;color:var(--c-text);line-height:1.35;word-break:break-word}.student-video-meta{display:flex;flex-wrap:wrap;gap:6px 10px;margin-top:6px;font-size:12px;color:var(--c-text-muted)}.student-video-desc{margin-top:4px;font-size:12px;color:var(--c-text-muted);overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.student-video-cta{flex-shrink:0;padding:8px 12px;border-radius:999px;background:var(--c-primary-soft);color:var(--c-primary-dark);font-size:13px;font-weight:700}@media (max-width: 900px){.app-shell.is-student .topbar{gap:10px}.app-shell.is-student .topbar-brand h1{font-size:20px}.app-shell.is-student .student-video-card{padding:16px 14px}.app-shell.is-student .assignment-group-head{margin-top:4px}}.incomplete-summary-bar{display:flex;flex-wrap:wrap;gap:12px 24px;margin:12px 0 16px;font-size:15px;font-weight:600;color:var(--c-primary-dark)}.incomplete-block-list{display:flex;flex-direction:column;gap:12px}.incomplete-block{padding:0;background:#fbfdff;border:1px solid var(--c-border);border-radius:var(--radius-md);overflow:hidden}.incomplete-block.is-expanded{border-color:#2563eb59}.incomplete-block-toggle{display:flex;align-items:center;justify-content:space-between;gap:12px;width:100%;padding:14px 16px;border:none;background:transparent;text-align:left;cursor:pointer}.incomplete-block-toggle:hover{background:rgba(37,99,235,.04)}.incomplete-block-head{margin-bottom:0;flex:1;min-width:0}.incomplete-chevron{flex-shrink:0;font-size:12px;color:var(--c-text-muted);line-height:1}.incomplete-student-list{list-style:none;margin:0;padding:0 16px 12px;border-top:1px solid var(--c-border)}.incomplete-student-list li{font-size:14px;color:var(--c-text);line-height:1.6;padding:6px 0;border-bottom:1px solid var(--c-border)}.incomplete-student-list li.is-completed{color:var(--c-text-muted)}.incomplete-student-list li.incomplete-all-done{color:var(--c-text-muted);font-style:italic}.incomplete-student-list li:last-child{border-bottom:none}.list-filter-bar input[type=date]{padding:8px 10px;border:1px solid var(--c-border);border-radius:var(--radius-sm);font-size:14px;color:var(--c-text);background:var(--c-surface)}