/* ===== 过滤器栏 ===== */
        .filter-bar {
            display: flex; gap: 8px; margin-bottom: 16px; flex-wrap: wrap; align-items: center;
        }
        .filter-btn {
            padding: 8px 18px; border: 2px solid #e2e8f0; background: white; border-radius: 20px;
            cursor: pointer; font-size: 14px; font-weight: 600; color: #4a5568; transition: all 0.2s;
        }
        .filter-btn:hover { border-color: #5a67d8; color: #5a67d8; }
        .filter-btn.active { background: #5a67d8; color: white; border-color: #5a67d8; }
        .filter-sep { width: 1px; height: 24px; background: #e2e8f0; margin: 0 4px; }
        .sort-btn {
            padding: 8px 16px; border: 2px solid #e2e8f0; background: white; border-radius: 20px;
            cursor: pointer; font-size: 13px; color: #718096; transition: all 0.2s;
        }
        .sort-btn.active { border-color: #ed8936; color: #ed8936; background: #fffaf0; }
        .btn-refresh {
            margin-left: auto; background: #48bb78; color: white; padding: 8px 20px;
            border: none; border-radius: 20px; cursor: pointer; font-size: 14px; font-weight: 600;
        }
        .btn-refresh:hover { background: #38a169; }

        /* ===== 搜索框 ===== */
        .search-bar {
            display: flex; gap: 8px; margin-bottom: 16px;
        }
        .search-bar input {
            flex: 1; padding: 9px 14px; border: 2px solid #e2e8f0; border-radius: 20px;
            font-size: 14px; outline: none; transition: border-color 0.2s;
        }
        .search-bar input:focus { border-color: #5a67d8; }
        .search-bar button {
            padding: 8px 20px; background: #5a67d8; color: white; border: none;
            border-radius: 20px; cursor: pointer; font-size: 14px; font-weight: 600;
        }
        .search-bar button:hover { background: #4c51bf; }

        /* ===== 卡片流（单列） ===== */
        .feed-grid {
            max-width: 720px; margin: 0 auto;
        }
        .feed-card {
            break-inside: avoid; background: white; border-radius: 12px; padding: 18px;
            margin-bottom: 16px; box-shadow: 0 2px 8px rgba(0,0,0,0.08);
            transition: box-shadow 0.2s, transform 0.2s;
            content-visibility: auto;            /* 屏外卡片跳过渲染：长 feed 滚动/首屏明显更顺 */
            contain-intrinsic-size: auto 300px;  /* 未渲染时占位尺寸，防滚动条跳动 */
        }
        .feed-card:hover { box-shadow: 0 8px 24px rgba(0,0,0,0.12); transform: translateY(-2px); }

        .feed-card .card-header {
            display: flex; align-items: center; gap: 8px; margin-bottom: 10px;
        }
        .type-badge {
            display: inline-block; padding: 3px 10px; border-radius: 12px;
            font-size: 11px; font-weight: 600;
        }
        .type-viewpoint { background: #bee3f8; color: #2a4365; }
        .type-mindmap { background: #e9d8fd; color: #44337a; }
        /* 画布权限徽章：💰付费/🔗分享/👥仅朋友（公开不显示） */
        .vis-badge { display: inline-block; padding: 2px 8px; border-radius: 10px; background: #fefcbf; color: #744210; font-size: 11px; font-weight: 600; vertical-align: middle; }
        /* 悬赏提问徽章：💰 金额 / 🎓 定向专家 */
        .bounty-badge { display: inline-block; padding: 2px 8px; border-radius: 10px; background: #feebc8; color: #c05621; font-size: 11px; font-weight: 600; vertical-align: middle; }
        /* 悬赏价头部大徽章：比正文行徽章更醒目（用户反馈"提问内容看不到价格"），免费提问也有标价消除迷惑 */
        .bounty-badge-lg { display: inline-block; padding: 3px 10px; border-radius: 12px; background: #feebc8; color: #9c4221; font-size: 12px; font-weight: 700; vertical-align: middle; border: 1px solid #f6ad55; }
        .free-badge-lg { display: inline-block; padding: 3px 10px; border-radius: 12px; background: #edf2f7; color: #718096; font-size: 12px; font-weight: 600; vertical-align: middle; border: 1px solid #cbd5e0; }
        .expert-badge { display: inline-block; padding: 2px 8px; border-radius: 10px; background: #e9d8fd; color: #6b46c1; font-size: 11px; font-weight: 600; vertical-align: middle; }
        .card-meta { font-size: 12px; color: #a0aec0; }

        .feed-card .card-title {
            font-size: 17px; font-weight: 700; color: #2d3748; margin-bottom: 6px;
        }
        /* 画布封面位：封面图已下线，统一渲染渐变占位（.card-cover-empty 居中装饰；img 规则留待封面功能恢复时用） */
        .feed-card .card-cover {
            height: 120px; border-radius: 8px; overflow: hidden; margin-bottom: 10px;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        }
        .feed-card .card-cover img { width: 100%; height: 100%; object-fit: cover; display: block; }
        .feed-card .card-cover-empty {
            display: flex; align-items: center; justify-content: center;
            color: rgba(255,255,255,.85); font-size: 34px;
        }
        .feed-card .card-body {
            font-size: 14px; line-height: 1.7; color: #4a5568; margin-bottom: 10px;
        }
        .feed-card .card-body img { max-width: 100%; border-radius: 8px; margin-top: 8px; }
        .feed-card .card-tags { margin-bottom: 8px; }
        .feed-card .card-tags .tag {
            display: inline-block; background: #edf2f7; color: #4a5568;
            padding: 2px 8px; border-radius: 4px; font-size: 12px; margin-right: 6px;
        }
        .feed-card .card-stats {
            display: flex; gap: 16px; font-size: 12px; color: #a0aec0; margin-bottom: 8px;
        }
        .feed-card .card-actions {
            display: flex; gap: 10px; padding-top: 10px; border-top: 1px solid #f0f0f0;
        }
        .card-actions button {
            padding: 5px 14px; font-size: 13px; border: 1px solid #e2e8f0;
            background: white; border-radius: 16px; cursor: pointer; transition: all 0.2s;
        }
        .card-actions button:hover { border-color: #5a67d8; color: #5a67d8; background: #ebf4ff; }
        /* 已赞/已踩的 👍/👎 高亮态（list.js renderFeedItems/toggleReaction 切换） */
        .card-actions button.reaction-on { border-color: #5a67d8; color: #5a67d8; background: #ebf4ff; font-weight: 600; }
        .card-actions .comment-count-badge {
            background: #fed7d7; color: #c53030; padding: 1px 6px; border-radius: 8px;
            font-size: 11px; margin-left: 4px;
        }

        /* ===== 评论区 ===== */
        .comment-section {
            margin-top: 12px; padding: 12px; background: #f7fafc; border-radius: 10px;
        }
        .comment-list { max-height: 300px; overflow-y: auto; margin-bottom: 10px; }
        .comment-item {
            padding: 8px 0; border-bottom: 1px solid #e2e8f0; font-size: 14px;
            animation: fadeIn 0.3s;
        }
        .comment-item:last-child { border-bottom: none; }
        .comment-item.new-comment { animation: highlightNew 1.5s; }
        @keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
        @keyframes highlightNew {
            0% { background: #c6f6d5; } 100% { background: transparent; }
        }
        .comment-item .c-meta { font-size: 12px; color: #718096; margin-bottom: 3px; }
        .comment-item .c-content { line-height: 1.5; }
        .comment-item .c-content img {
            max-width: 180px; border-radius: 8px; margin-top: 6px; cursor: zoom-in;
            transition: transform 0.2s;
        }
        .comment-item .c-content img:hover { transform: scale(1.05); }

        .comment-input-area { display: flex; gap: 8px; align-items: flex-end; }
        .comment-input-area textarea {
            flex: 1; padding: 8px 10px; border: 1px solid #ddd; border-radius: 8px;
            font-size: 14px; min-height: 50px; resize: vertical; font-family: inherit;
        }
        .comment-btns { display: flex; flex-direction: column; gap: 4px; }
        .comment-btns button {
            padding: 5px 10px; font-size: 12px; border: none; border-radius: 6px;
            cursor: pointer; white-space: nowrap;
        }
        .btn-send { background: #5a67d8; color: white; }
        .btn-img { background: #ed8936; color: white; }
        .btn-sticker { background: #9f7aea; color: white; }
        /* 语音输入：录音中（.recording，voice-stt.js 切换）变红提示再点停止 */
        .btn-voice { background: #38a169; color: white; }
        .btn-voice.recording { background: #e53e3e; }

        /* ===== 斗图面板 ===== */
        .sticker-panel {
            display: none; margin-top: 8px; padding: 10px; background: white;
            border: 1px solid #e2e8f0; border-radius: 10px;
        }
        .sticker-panel.show { display: block; }
        .sticker-grid {
            display: grid; grid-template-columns: repeat(8, 1fr); gap: 4px;
        }
        .sticker-grid span {
            font-size: 28px; cursor: pointer; padding: 4px; text-align: center;
            border-radius: 6px; transition: background 0.15s;
        }
        .sticker-grid span:hover { background: #edf2f7; }

        /* ===== 加载更多 / 底部提示 ===== */
        .load-more { text-align: center; padding: 20px; }
        .load-more button {
            padding: 10px 30px; background: #5a67d8; color: white; border: none;
            border-radius: 20px; cursor: pointer; font-size: 14px;
        }
        .feed-hint { text-align: center; padding: 16px; font-size: 13px; color: #a0aec0; }

        /* ===== 图片放大遮罩 ===== */
        .img-overlay {
            display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%;
            background: rgba(0,0,0,0.85); z-index: 9999; cursor: zoom-out;
            justify-content: center; align-items: center;
        }
        .img-overlay.show { display: flex; }
        .img-overlay img {
            max-width: 90%; max-height: 90%; border-radius: 8px;
            box-shadow: 0 8px 40px rgba(0,0,0,0.5);
        }

        .hidden-file { display: none; }
        .stance { display: inline-block; padding: 2px 8px; border-radius: 4px; font-size: 11px; font-weight: 600; }
        .stance-SP { background: #c6f6d5; color: #22543d; }
        .stance-LP { background: #bee3f8; color: #2a4365; }
        .stance-N { background: #e2e8f0; color: #2d3748; }
        .stance-Q { background: #fefcbf; color: #744210; }
        .stance-SC { background: #fed7d7; color: #742a2a; }
        .stance-LC { background: #feebc8; color: #7b341e; }

        /* ===== 搜索模式 Tab ===== */
        .search-tabs {
            display: flex; gap: 8px; margin-bottom: 10px;
        }
        .search-tab {
            padding: 7px 18px; border: 2px solid #e2e8f0; background: white; border-radius: 20px;
            cursor: pointer; font-size: 13px; font-weight: 600; color: #718096; transition: all 0.2s;
        }
        .search-tab:hover { border-color: #5a67d8; color: #5a67d8; }
        .search-tab.active { background: #5a67d8; color: white; border-color: #5a67d8; }


        /* ===== 大喇叭广播（金色置顶卡 + 徽标 + 倒计时） ===== */
        .horn-card {
            border: 2px solid #f6c453;
            background: linear-gradient(180deg, #fffdf5 0%, #ffffff 100%);
            box-shadow: 0 2px 12px rgba(246,196,83,0.35);
        }
        .horn-badge {
            display: inline-block; padding: 3px 10px; border-radius: 12px;
            background: linear-gradient(135deg, #f6c453 0%, #ed8936 100%);
            color: #fff; font-size: 11px; font-weight: 700;
        }
        .horn-countdown { font-size: 12px; color: #c05621; font-weight: 600; }

        /* ===== 提问区（专属筛选行 + 学科/提问徽标） ===== */
        .question-bar { display: flex; gap: 8px; margin: -8px 0 16px; flex-wrap: wrap; align-items: center; }
        .q-sort-btn {
            padding: 6px 14px; border: 2px solid #e2e8f0; background: white; border-radius: 18px;
            cursor: pointer; font-size: 13px; color: #718096; transition: all 0.2s;
        }
        .q-sort-btn.active { border-color: #ed8936; color: #ed8936; background: #fffaf0; }
        .question-bar select {
            padding: 6px 10px; border: 2px solid #e2e8f0; border-radius: 18px;
            font-size: 13px; color: #4a5568; background: white; cursor: pointer;
        }
        .subject-badge { display: inline-block; padding: 2px 8px; border-radius: 10px; background: #c6f6d5; color: #276749; font-size: 11px; font-weight: 600; vertical-align: middle; }
        .q-badge { display: inline-block; padding: 2px 8px; border-radius: 10px; background: #bee3f8; color: #2b6cb0; font-size: 11px; font-weight: 600; vertical-align: middle; }

        /* ===== 移动端适配（≤768px） ===== */
        @media (max-width: 768px) {
            /* 搜索模式 tab / 过滤器栏：整排可横向滑动，不在窄屏挤换行 */
            .search-tabs, .filter-bar {
                flex-wrap: nowrap; overflow-x: auto; -webkit-overflow-scrolling: touch;
                scrollbar-width: none; padding-bottom: 4px;
            }
            .search-tabs::-webkit-scrollbar, .filter-bar::-webkit-scrollbar { display: none; }
            .search-tab, .filter-btn, .sort-btn, .btn-refresh { flex: 0 0 auto; white-space: nowrap; min-height: 36px; }
            .filter-sep { flex: 0 0 1px; }
            /* 搜索框：输入 16px 防 iOS 自动放大 */
            .search-bar input { font-size: 16px; min-height: 40px; }
            .search-bar button { min-height: 40px; flex: 0 0 auto; }
            /* feed 卡片全宽、内边距收紧，操作按钮允许换行且 ≥36px */
            .feed-card { padding: 14px; border-radius: 10px; }
            .feed-card .card-actions { flex-wrap: wrap; }
            .card-actions button { padding: 8px 14px; min-height: 36px; }
            .comment-input-area textarea { font-size: 16px; }
            .comment-btns button { padding: 8px 12px; min-height: 36px; }
            .load-more button { min-height: 44px; }
        }

        /* ===== 举报弹窗 + 轻提示 ===== */
        .report-overlay {
            position: fixed; inset: 0; background: rgba(0,0,0,.45); z-index: 9999;
            display: flex; align-items: center; justify-content: center;
        }
        .report-overlay.hidden { display: none; }
        .report-card {
            background: white; border-radius: 12px; padding: 20px; width: 90%; max-width: 420px;
            box-shadow: 0 20px 60px rgba(0,0,0,.3);
        }
        .report-card h3 { margin: 0 0 14px; color: #4a5568; font-size: 16px; }
        .report-actions { display: flex; justify-content: flex-end; gap: 10px; }
        .report-actions .btn { width: auto; }
        .report-toast {
            position: fixed; left: 50%; bottom: 60px; transform: translateX(-50%);
            background: rgba(0,0,0,.78); color: white; padding: 10px 20px; border-radius: 20px;
            font-size: 14px; opacity: 0; transition: opacity .25s; pointer-events: none; z-index: 10001;
        }
        .report-toast.show { opacity: 1; }
        /* 评论行内的小举报入口 */
        .c-report { color: #cbd5e0; cursor: pointer; font-size: 12px; margin-left: 6px; }
        .c-report:hover { color: #e53e3e; }
        /* 评论点赞按钮（评论区悬赏模式）：悬赏超时按最高赞结算 */
        .c-like-btn { border: none; background: transparent; color: #718096; cursor: pointer; font-size: 12px; margin-left: 8px; padding: 1px 6px; border-radius: 10px; }
        .c-like-btn:hover { background: #edf2f7; }
        .c-like-btn.liked { color: #d69e2e; font-weight: 700; background: #fffbeb; }