:root { --primary: #2c5282; --accent: #d4a84b; --light: #f8fafc; --gray: #6b7280; --white: #ffffff; --transition: 0.3s ease; }
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body { font-family: 'Inter', 'Segoe UI', Arial, sans-serif; color: var(--primary); line-height: 1.7; }
    body > header { background: #1e3a5f; position: sticky; top: 0; z-index: 1000; }
    header nav { max-width: 1200px; margin: 0 auto; padding: 12px 24px; display: flex; justify-content: space-between; align-items: center; }
    .logo { color: var(--white); font-weight: 700; font-size: 20px; text-decoration: none; }
    .nav-links { display: flex; gap: 8px; list-style: none; }
    .nav-links a { color: rgba(255,255,255,0.88); padding: 8px 14px; border-radius: 6px; font-size: 14px; text-decoration: none; }
    .nav-links a.active { background: rgba(255,255,255,0.15); }
    .breadcrumb { background: var(--light); padding: 12px 0; border-bottom: 1px solid rgba(26,60,110,0.08); }
    .breadcrumb-inner { max-width: 1200px; margin: 0 auto; padding: 0 24px; font-size: 13px; color: var(--gray); }
    .breadcrumb-inner a { color: var(--primary); text-decoration: none; }
    .breadcrumb-inner a:hover { text-decoration: underline; }
    .breadcrumb-sep { margin: 0 8px; color: var(--gray); }
    .article-header { background: linear-gradient(135deg, #1d6b3a, #145a32); padding: 60px 24px; text-align: center; color: var(--white); }
    .article-header h1 { font-size: 32px; margin-bottom: 16px; }
    .article-header p { opacity: 0.8; }
    /* ===== ARTICLE LAYOUT WITH SIDEBAR ===== */
    .article-layout {
      max-width: 1200px; margin: 0 auto;
      padding: 48px 24px;
      display: grid;
      grid-template-columns: 1fr 340px;
      gap: 40px;
    }
    @media (max-width: 1024px) {
      .article-layout { grid-template-columns: 1fr; }
    }

    /* ===== ARTICLE CONTENT ===== */
    .article-container {
      max-width: 100%;
      padding: 48px 24px;
    }

    /* ===== SIDEBAR ===== */
    .sidebar { display: flex; flex-direction: column; gap: 24px; }
    .sidebar-card {
      background: var(--white); border-radius: var(--radius);
      box-shadow: var(--shadow);
      border: 1px solid rgba(26,60,110,0.07);
      overflow: hidden;
    }
    .sidebar-card .sidebar-head {
      background: var(--primary); color: var(--white);
      padding: 14px 20px; font-size: 14px; font-weight: 700;
      letter-spacing: 0.5px;
    }
    .sidebar-card .sidebar-body { padding: 20px; }
    .cat-list { list-style: none; }
    .cat-list li {
      display: flex; justify-content: space-between; align-items: center;
      padding: 10px 0;
      border-bottom: 1px solid rgba(26,60,110,0.06);
    }
    .cat-list li:last-child { border-bottom: none; }
    .cat-list a {
      font-size: 13px; color: var(--dark); font-weight: 500;
      transition: var(--transition);
    }
    .cat-list a:hover { color: var(--primary); }
    .cat-list .count {
      background: rgba(26,60,110,0.08);
      color: var(--primary); padding: 3px 9px;
      border-radius: 20px; font-size: 11px; font-weight: 700;
    }
    .popular-post {
      display: flex; gap: 12px; align-items: flex-start;
      padding: 12px 0;
      border-bottom: 1px solid rgba(26,60,110,0.06);
    }
    .popular-post:last-child { border-bottom: none; }
    .popular-num {
      width: 28px; height: 28px; flex-shrink: 0;
      background: var(--primary); color: var(--white);
      border-radius: 50%;
      display: flex; align-items: center; justify-content: center;
      font-size: 12px; font-weight: 700;
      margin-top: 2px;
    }
    .popular-info h4 {
      font-size: 13px; font-weight: 600; color: var(--dark);
      margin-bottom: 4px; line-height: 1.4;
    }
    .popular-info h4 a:hover { color: var(--primary); }
    .popular-info span { font-size: 11px; color: var(--gray); }
    .sidebar-cta {
      background: linear-gradient(135deg, var(--primary), #1a3c6e);
      border-radius: var(--radius);
      padding: 24px;
      color: var(--white);
      text-align: center;
    }
    .sidebar-cta h3 { font-size: 16px; font-weight: 700; margin-bottom: 8px; }
    .sidebar-cta p { font-size: 13px; opacity: 0.9; margin-bottom: 16px; }
    .sidebar-cta a {
      display: inline-block;
      background: var(--accent); color: var(--primary);
      padding: 12px 24px; border-radius: 8px;
      font-size: 13px; font-weight: 700;
      transition: var(--transition);
    }
    .sidebar-cta a:hover { background: #f5b840; }
    .article-content h2 { font-size: 24px; margin: 32px 0 16px; }
    .article-content h3 { font-size: 20px; margin: 24px 0 12px; color: var(--primary); }
    .article-content p { margin-bottom: 16px; color: #374151; }
    .article-cta { background: var(--light); padding: 32px; text-align: center; margin: 48px 0; border-radius: 12px; }
    .article-cta a { display: inline-block; background: var(--primary); color: var(--white); padding: 14px 32px; border-radius: 8px; text-decoration: none; font-weight: 700; }
    .related-posts { background: var(--light); padding: 60px 24px; }
    .related-posts-inner { max-width: 1200px; margin: 0 auto; }
    .related-posts h2 { font-size: 24px; font-weight: 700; color: var(--primary); margin-bottom: 24px; text-align: center; }
    .related-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
    .related-card { background: var(--white); border-radius: 14px; overflow: hidden; box-shadow: 0 4px 24px rgba(30,58,95,0.08); border: 1px solid rgba(26,60,110,0.07); text-decoration: none; transition: 0.3s ease; }
    .related-card:hover { transform: translateY(-4px); }
    .related-card-img { height: 140px; background: linear-gradient(135deg, #1a3c6e, #2a5298); display: flex; align-items: center; justify-content: center; font-size: 48px; opacity: 0.6; }
    .related-card-body { padding: 20px; }
    .related-card-body h3 { font-size: 15px; font-weight: 700; color: var(--primary); margin-bottom: 8px; }
    .related-card-body p { font-size: 13px; color: var(--gray); }
    footer { background: var(--primary); color: var(--white); padding: 40px 24px; margin-top: 60px; text-align: center; }
    @media (max-width: 1024px) {
      .article-layout { grid-template-columns: 1fr; }
      .sidebar { display: none; }
    }
    @media (max-width: 768px) { .related-grid { grid-template-columns: 1fr; } }
  
    .hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; }
    .hamburger span { display: block; width: 24px; height: 2px; background: #fff; border-radius: 2px; }
    .lang-switcher { display: flex; align-items: center; gap: 4px; margin-left: 12px; padding-left: 12px; border-left: 1px solid rgba(255,255,255,0.2); }
    .lang-switcher a { color: rgba(255,255,255,0.7); text-decoration: none; font-size: 13px; font-weight: 500; padding: 6px 10px; border-radius: 4px; transition: var(--transition); }
    .lang-switcher a.active { color: #fff; font-weight: 700; background: rgba(255,255,255,0.15); }
    .lang-switcher a:hover:not(.active) { background: rgba(255,255,255,0.1); color: #fff; }
    @media (max-width: 768px) {
      header .nav-links, nav .nav-links { display: none; position: absolute; top: 56px; left: 0; right: 0; background: #1e3a5f; flex-direction: column; padding: 16px; gap: 4px; }
      header .nav-links.open, nav .nav-links.open { display: flex; }
      header .hamburger, nav .hamburger { display: flex; }
    }

  
    /* ===== TOPIC CLUSTER DROPDOWN NAV ===== */
    .dropdown { position: relative; }
    .dropdown > a::after,
    .dropbtn::after { content: " ▼"; font-size: 10px; opacity: 0.7; margin-left: 4px; }
    .dropdown-content {
      display: none; position: absolute; top: 100%; left: 0;
      background: var(--primary, #1a1a1a); min-width: 220px;
      box-shadow: 0 12px 30px rgba(0,0,0,0.25); border-radius: 8px;
      padding: 8px 0; list-style: none; z-index: 1000;
    }
    .dropdown-content a {
      display: block; padding: 10px 18px; color: rgba(255,255,255,0.9);
      font-size: 14px; white-space: nowrap; text-decoration: none;
    }
    .dropdown-content a:hover { background: rgba(255,255,255,0.12); color: #fff; }
    .dropdown:hover .dropdown-content { display: block; }
    .dropdown-header {
      padding: 8px 18px; font-size: 12px; text-transform: uppercase;
      letter-spacing: 0.5px; color: var(--accent, #e8a020); font-weight: 700;
    }
    .dropdown-divider { height: 1px; background: rgba(255,255,255,0.12); margin: 6px 0; }
    @media (max-width: 991px) {
      .dropdown-content { position: static; box-shadow: none; background: rgba(0,0,0,0.15); min-width: auto; margin-left: 12px; }
      .dropdown-content a { padding: 8px 16px; }
    }
    button.hamburger { background: transparent; border: none; padding: 8px; }