:root {
    --td-primary: #0056b3; /* Xanh dương TravelyData */
    --td-primary-hover: #004494;
    --td-text-main: #1e293b;
    --td-text-muted: #64748b;
    --td-border: #e2e8f0;
    --td-bg-light: #f8fafc;
}

/* 1. Live Search (Hero Section Style) */
.td-search-wrapper { position: relative; width: 100%; max-width: 700px; margin: 0 auto; }
.td-search-icon { position: absolute; left: 16px; top: 50%; transform: translateY(-50%); color: var(--td-text-muted); display: flex; align-items: center; }
.td-search-input { width: 100%; padding: 18px 20px 18px 48px; border: 1px solid var(--td-border); border-radius: 8px; font-size: 16px; color: var(--td-text-main); box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05); transition: all 0.3s ease; background: #fff; box-sizing: border-box; }
.td-search-input:focus { outline: none; border-color: var(--td-primary); box-shadow: 0 10px 25px -5px rgba(0, 86, 179, 0.15); }
.td-search-results { position: absolute; top: calc(100% + 8px); left: 0; right: 0; background: #fff; border-radius: 8px; box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1); z-index: 9999; max-height: 350px; overflow-y: auto; border: 1px solid var(--td-border); }
.td-search-results ul { list-style: none; margin: 0; padding: 0; }
.td-search-results li { border-bottom: 1px solid var(--td-bg-light); }
.td-search-results li:last-child { border-bottom: none; }
.td-search-results li a { display: block; padding: 14px 20px; color: var(--td-text-main); text-decoration: none; font-weight: 500; transition: background 0.2s; }
.td-search-results li a:hover { background: var(--td-bg-light); color: var(--td-primary); }

/* 2. TOC (Sticky & Minimalist) */
.td-toc-container { position: sticky; top: 30px; padding: 24px; background: #fff; border-radius: 8px; border: 1px solid var(--td-border); box-shadow: 0 1px 3px rgba(0,0,0,0.05); }
.td-toc-title { margin-top: 0; margin-bottom: 16px; font-size: 15px; font-weight: 700; color: var(--td-text-main); text-transform: uppercase; letter-spacing: 0.5px; }
.td-toc-list { list-style: none; padding: 0; margin: 0; }
.td-toc-list li { margin-bottom: 12px; }
.td-toc-list li.toc-level-3 { padding-left: 16px; font-size: 0.95em; }
.td-toc-link { color: var(--td-text-muted); text-decoration: none; transition: all 0.2s; display: block; line-height: 1.5; font-size: 14px; }
.td-toc-link:hover, .td-toc-link.active { color: var(--td-primary); font-weight: 600; }

/* 3. Voting Box */
.td-voting-box { margin-top: 50px; padding: 30px; border: 1px solid var(--td-border); border-radius: 8px; background: #fff; text-align: center; box-shadow: 0 1px 3px rgba(0,0,0,0.02); }
.td-voting-title { margin-top: 0; margin-bottom: 20px; font-size: 18px; font-weight: 600; color: var(--td-text-main); }
.td-voting-actions { display: flex; justify-content: center; gap: 16px; }
.td-vote-btn { display: inline-flex; align-items: center; gap: 8px; padding: 10px 24px; border: 1px solid var(--td-border); background: #fff; border-radius: 6px; font-weight: 500; color: var(--td-text-main); cursor: pointer; transition: all 0.2s; font-size: 15px; }
.td-vote-btn:hover:not(:disabled) { background: var(--td-bg-light); border-color: var(--td-primary); color: var(--td-primary); }
.td-vote-btn.voted-active { background: var(--td-primary); color: #fff; border-color: var(--td-primary); }
.td-vote-btn:disabled { opacity: 0.6; cursor: not-allowed; }

/* 4. Sidebar Menu Tree */
.td-sidebar-menu { background: #fff; border-radius: 8px; border: 1px solid var(--td-border); padding: 20px; box-shadow: 0 1px 3px rgba(0,0,0,0.05); }
.td-menu-group { margin-bottom: 12px; }
.td-menu-category { margin: 0; padding: 10px 12px; font-size: 15px; font-weight: 600; color: var(--td-text-main); cursor: pointer; display: flex; justify-content: space-between; align-items: center; border-radius: 6px; transition: background 0.2s; user-select: none; }
.td-menu-category:hover { background: var(--td-bg-light); color: var(--td-primary); }
.td-menu-category.active { color: var(--td-primary); }
.td-toggle-icon { font-size: 18px; font-weight: 400; color: var(--td-text-muted); line-height: 1; }
.td-menu-category.active .td-toggle-icon { color: var(--td-primary); }
.td-menu-posts { list-style: none; padding: 0 0 0 16px; margin: 8px 0 0 0; border-left: 1px solid var(--td-border); margin-left: 18px; }
.td-menu-posts li { margin-bottom: 10px; }
.td-menu-posts li:last-child { margin-bottom: 0; }
.td-menu-post-link { color: var(--td-text-muted); text-decoration: none; font-size: 14px; transition: color 0.2s; display: block; line-height: 1.4; }
.td-menu-post-link:hover, .td-menu-post-link.current { color: var(--td-primary); font-weight: 600; }