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20px;cursor:pointer}.admin-course-item:hover{border-color:var(--accent)}.admin-course-emoji{width:48px;height:48px;border-radius:12px;display:grid;place-items:center;font-size:1.5rem;flex-shrink:0}.admin-course-open{color:var(--accent);font-weight:700;font-size:.85rem}.emoji-picker{display:flex;flex-wrap:wrap;gap:6px}.emoji-opt{width:38px;height:38px;border-radius:var(--radius-sm);border:1px solid var(--line);background:var(--bg);font-size:1.1rem}.emoji-opt.active{border-color:var(--accent);background:var(--accent-soft)}.tracking-table th,.tracking-table td{vertical-align:middle}.track-course-emoji{margin-right:6px}.track-course-name{font-size:.8rem}.track-row{cursor:pointer}.track-cell{display:flex;align-items:center;gap:8px}.track-mini{width:70px;height:6px;background:var(--bg-3);border-radius:4px;overflow:hidden}.track-mini-fill{height:100%;background:var(--accent)}.track-cell-txt{font-size:.78rem;color:var(--tx-2);white-space:nowrap}.detail-lessons{list-style:none;margin-top:10px;display:flex;flex-direction:column;gap:6px}.detail-lessons li{display:flex;align-items:center;gap:10px;font-size:.85rem}.detail-date{margin-left:auto;font-size:.78rem}.editor{display:flex;flex-direction:column;height:calc(100vh - var(--head-h))}.editor-head{display:flex;align-items:center;gap:20px;padding:12px clamp(16px,3vw,32px);border-bottom:1px solid var(--line);background:var(--bg-1);flex-wrap:wrap}.editor-head .back-link{margin-bottom:0}.editor-head-title{display:flex;align-items:center;gap:12px}.editor-emoji{width:42px;height:42px;border-radius:11px;display:grid;place-items:center;font-size:1.4rem}.editor-body{flex:1;display:flex;min-height:0}.editor-tree{width:320px;flex-shrink:0;border-right:1px solid var(--line);overflow-y:auto;padding:18px;background:var(--bg-1)}.editor-tree-title{font-size:.72rem;text-transform:uppercase;letter-spacing:.08em;color:var(--tx-3);font-weight:700}.tree-module{margin-bottom:8px}.tree-module-head{display:flex;align-items:center;gap:8px;padding:8px;border-radius:var(--radius-sm)}.tree-module-head:hover{background:var(--bg-2)}.tree-module-icon{font-size:1rem}.tree-module-title{flex:1;min-width:0;font-weight:700;font-size:.87rem;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.tree-actions{display:flex;gap:1px;opacity:0;transition:opacity .15s}.tree-module-head:hover .tree-actions,.tree-lesson:hover .tree-actions{opacity:1}.tree-actions button{width:24px;height:24px;border:none;background:none;color:var(--tx-2);border-radius:5px;font-size:.78rem}.tree-actions button:hover:not(:disabled){background:var(--bg-3);color:var(--tx)}.tree-actions button:disabled{opacity:.25}.tree-actions button.danger:hover{color:var(--danger)}.tree-lessons{list-style:none;margin:2px 0 6px 14px;border-left:1px solid var(--line)}.tree-lesson{display:flex;align-items:center;gap:6px;padding:7px 8px 7px 12px;cursor:pointer;border-radius:0 var(--radius-sm) var(--radius-sm) 0}.tree-lesson:hover{background:var(--bg-2)}.tree-lesson.active{background:var(--accent-soft)}.tree-lesson-title{flex:1;min-width:0;font-size:.84rem;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.tree-lesson.active .tree-lesson-title{color:var(--accent);font-weight:600}.tree-add{padding:7px 12px;font-size:.82rem;color:var(--tx-3);cursor:pointer;border-radius:var(--radius-sm)}.tree-add:hover{color:var(--accent);background:var(--bg-2)}.editor-main{flex:1;overflow-y:auto;padding:24px clamp(16px,3vw,36px)}.lesson-editor{max-width:900px}.lesson-editor-bar{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px;padding-bottom:14px;border-bottom:1px solid var(--line);position:sticky;top:-24px;background:var(--bg);z-index:5;padding-top:4px}.lesson-editor-foot{margin-top:20px;padding-top:18px;border-top:1px solid var(--line)}.tab-switch{display:inline-flex;background:var(--bg-2);border-radius:var(--radius-sm);padding:3px}.tab-switch button{border:none;background:none;color:var(--tx-2);padding:5px 14px;border-radius:6px;font-size:.82rem;font-weight:600}.tab-switch button.active{background:var(--accent);color:#0c0f13}.preview-box{border:1px solid var(--line);border-radius:var(--radius-sm);padding:20px;background:var(--bg-1);min-height:340px}.resource-row{display:flex;gap:8px;align-items:center}.resource-row .input{flex:1}@media (max-width: 780px){.shell-nav{display:none}.course-hero,.editor-body{flex-direction:column}.editor-tree{width:100%;border-right:none;border-bottom:1px solid var(--line);max-height:40vh}.editor{height:auto}.reader-actions{width:100%}}