:root {
        --prussian-blue: #0d47a1;
        --light-blue: #e3f2fd;
        --accent-teal: #00897b;
        --background-color: #f5f7fa;
        --card-background: #ffffff;
        --text-color: #495057;
        --heading-color: #212529;
        --border-color: #dee2e6;
        --shadow-color: rgba(0, 0, 0, 0.06);
      }

      * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
      }

      body {
        font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
        line-height: 1.8;
        color: var(--text-color);
        background-color: var(--background-color);
        -webkit-font-smoothing: antialiased;
        -moz-osx-font-smoothing: grayscale;
      }

      header {
        background: var(--card-background);
        padding: 3rem 2rem;
        text-align: center;
        border-bottom: 1px solid var(--border-color);
      }

      .logo-container {
        display: flex;
        justify-content: center;
        align-items: center;
        gap: 1rem;
        margin-bottom: 1rem;
      }

      .site-logo {
        width: 50px;
        height: 50px;
      }

      header h1 {
        font-weight: 700;
        font-size: 2.5rem;
        color: var(--heading-color);
      }

      header p {
        font-size: 1.1rem;
        color: var(--text-color);
        max-width: 600px;
        margin: 0 auto;
      }

      .nav-tabs {
        display: flex;
        justify-content: center;
        gap: 1rem;
        padding: 1rem;
        background: var(--card-background);
        border-bottom: 1px solid var(--border-color);
        position: sticky;
        top: 0;
        z-index: 1000;
        box-shadow: 0 2px 10px var(--shadow-color);
      }

      .nav-tab {
        padding: 0.6rem 1.3rem;
        cursor: pointer;
        border: 1px solid var(--border-color);
        background: none;
        color: var(--prussian-blue);
        font-size: 1rem;
        font-weight: 500;
        transition: all 0.3s ease;
        border-radius: 50px;
      }

      .nav-tab:hover {
        background-color: var(--light-blue);
        border-color: var(--prussian-blue);
      }

      .nav-tab.active {
        color: white;
        background-color: var(--prussian-blue);
        border-color: var(--prussian-blue);
        box-shadow: 0 2px 8px rgba(13, 71, 161, 0.3);
      }

      main {
        padding: 3rem 2rem;
      }

      .guidelines-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
        gap: 2rem;
        max-width: 1500px;
        margin: 0 auto;
      }

      .section { display: none; }
      .section.active { display: grid; }

      .guideline-card {
        background: var(--card-background);
        border-radius: 8px;
        padding: 2rem;
        border: 1px solid var(--border-color);
        box-shadow: 0 4px 12px var(--shadow-color);
        transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
        opacity: 0;
        transform: translateY(20px);
      }

      .guideline-card:hover {
        transform: translateY(-5px);
        box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
        border-color: var(--prussian-blue);
      }

      .category-icon {
        width: 42px;
        height: 42px;
        margin-bottom: 1.5rem;
        color: var(--prussian-blue);
      }

      .guideline-card h3 {
        color: var(--heading-color);
        margin-bottom: 1.2rem;
        font-size: 1.3rem;
        font-weight: 700;
      }

      .guidelines-list {
        list-style: none;
      }

      .guidelines-list li {
        margin-bottom: 0.8rem;
      }

      .guidelines-list a {
        color: var(--text-color);
        text-decoration: none;
        display: flex;
        align-items: center;
        gap: 0.8rem;
        transition: color 0.3s ease, transform 0.3s ease;
      }

      .guidelines-list a:hover {
        color: var(--accent-teal);
        transform: translateX(4px);
      }

      .search-container {
        margin-top: 2rem;
      }

      #search-box {
        width: 100%;
        max-width: 500px;
        padding: 0.9rem 1.2rem;
        border: 1px solid var(--border-color);
        border-radius: 50px;
        font-size: 1rem;
        color: var(--text-color);
        transition: all 0.3s ease;
      }
      
      #search-box::placeholder {
        color: #aaa;
      }

      #search-box:focus {
        outline: none;
        border-color: var(--prussian-blue);
        box-shadow: 0 0 0 3px rgba(13, 71, 161, 0.1);
      }

      footer {
        text-align: center;
        padding: 3rem 2rem;
        background: #e9ecef;
        color: #6c757d;
        border-top: 1px solid var(--border-color);
      }

      footer a {
        color: var(--prussian-blue);
        text-decoration: none;
        font-weight: 500;
        transition: color 0.3s ease;
      }

      footer a:hover {
        color: var(--accent-teal);
        text-decoration: underline;
      }

      /* Responsive Design */
      @media (max-width: 992px) {
        .guidelines-grid {
          grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
          gap: 1.5rem;
        }
      }

      @media (max-width: 768px) {
        body { font-size: 0.95rem; }
        header { padding: 2.5rem 1.5rem; }
        header h1 { font-size: 2rem; }
        main { padding: 2rem 1.5rem; }
        .guidelines-grid { grid-template-columns: 1fr; }
        .nav-tabs { gap: 0.8rem; padding: 1rem; }
        .nav-tab { padding: 0.6rem 1.2rem; font-size: 0.95rem; }
      }

      @media (max-width: 480px) {
        body { font-size: 0.9rem; }
        header { padding: 2rem 1rem; }
        header h1 { font-size: 1.6rem; }
        .logo-container { flex-direction: column; gap: 0.5rem; }
        main { padding: 1.5rem 1rem; }
        .guidelines-grid { gap: 1.5rem; }
        .guideline-card { padding: 1.5rem; }
        .nav-tabs { flex-wrap: wrap; }
        .nav-tab { padding: 0.5rem 1rem; }
        #search-box { padding: 0.8rem 1.2rem; }
      }