/* roulang page: index */
:root {
      --primary-deep: #4B0082;
      --primary-cyan: #00BFFF;
      --primary-gradient: linear-gradient(135deg, #4B0082 0%, #00BFFF 100%);
      --accent-amber: #FF8C00;
      --accent-green: #00FA9A;
      --bg-light: #F5F3F7;
      --card-white: #FFFFFF;
      --text-dark: #1E1E2F;
      --text-muted: #6B6B80;
      --border-light: rgba(75, 0, 130, 0.1);
      --shadow-card: 0 4px 20px rgba(75, 0, 130, 0.08);
      --shadow-hover: 0 8px 30px rgba(75, 0, 130, 0.15);
      --radius-card: 16px;
      --radius-btn: 30px;
      --radius-chip: 40px;
      --font-heading: 'Noto Sans SC', 'Inter', sans-serif;
      --font-body: 'Noto Sans SC', 'Inter', sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-body);
      background-color: var(--bg-light);
      color: var(--text-dark);
      line-height: 1.7;
      margin: 0;
      padding: 0;
      overflow-x: hidden;
    }
    h1, h2, h3, h4, .navbar-brand, .chip-nav, .btn {
      font-family: var(--font-heading);
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container {
      max-width: 1200px;
      padding-left: 20px;
      padding-right: 20px;
    }
    /* 自定义导航 */
    .db-navbar {
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(10px);
      box-shadow: 0 4px 12px rgba(0,0,0,0.02);
      padding: 16px 0;
      position: sticky;
      top: 0;
      z-index: 1000;
    }
    .logo-text {
      font-weight: 700;
      font-size: 1.8rem;
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 1px;
      margin-right: 20px;
    }
    .btn-primary-custom {
      background: var(--primary-gradient);
      border: none;
      color: #fff;
      border-radius: var(--radius-btn);
      padding: 10px 24px;
      font-weight: 600;
      transition: all 0.3s ease;
      box-shadow: 0 4px 12px rgba(0, 191, 255, 0.3);
      white-space: nowrap;
    }
    .btn-primary-custom:hover {
      background: linear-gradient(135deg, #3c0068 0%, #0099cc 100%);
      box-shadow: 0 6px 18px rgba(75, 0, 130, 0.4);
      color: #fff;
      transform: translateY(-1px);
    }
    .btn-outline-custom {
      background: transparent;
      border: 2px solid #4B0082;
      color: #4B0082;
      border-radius: var(--radius-btn);
      padding: 10px 24px;
      font-weight: 600;
      transition: all 0.3s ease;
    }
    .btn-outline-custom:hover {
      background: rgba(75, 0, 130, 0.05);
      border-color: #00BFFF;
      color: #00BFFF;
    }
    .chip-nav-container {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-top: 12px;
      padding: 4px 0;
    }
    .chip-nav {
      background: rgba(75, 0, 130, 0.05);
      color: #4B0082;
      border-radius: var(--radius-chip);
      padding: 8px 20px;
      font-weight: 500;
      font-size: 0.95rem;
      transition: all 0.25s;
      white-space: nowrap;
      border: none;
    }
    .chip-nav.active {
      background: var(--accent-amber);
      color: #fff;
      box-shadow: 0 4px 10px rgba(255,140,0,0.25);
    }
    .chip-nav:hover:not(.active) {
      background: rgba(75, 0, 130, 0.12);
      color: #2c0050;
    }
    /* Hero */
    .hero-section {
      padding: 60px 0 80px;
      background: linear-gradient(180deg, #F5F3F7 0%, #fff 100%);
    }
    .hero-image-card {
      background: var(--primary-gradient);
      border-radius: 24px;
      overflow: hidden;
      position: relative;
      box-shadow: var(--shadow-card);
    }
    .hero-image-card img {
      opacity: 0.9;
      mix-blend-mode: overlay;
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    .play-icon-overlay {
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      font-size: 3rem;
      color: rgba(255,255,255,0.9);
      text-shadow: 0 0 20px rgba(0,0,0,0.3);
    }
    .data-badge {
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(6px);
      border-radius: 40px;
      padding: 6px 18px;
      font-weight: 600;
      font-size: 0.9rem;
      color: var(--text-dark);
      box-shadow: 0 4px 10px rgba(0,0,0,0.05);
      display: inline-flex;
      align-items: center;
      gap: 4px;
      margin: 6px;
    }
    .data-badge .number {
      color: var(--accent-amber);
      font-weight: 700;
      font-size: 1.1rem;
    }
    /* 卡片系统 */
    .card-custom {
      background: var(--card-white);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      border: none;
      padding: 28px;
      transition: all 0.3s ease;
      height: 100%;
    }
    .card-custom:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .card-emphasis {
      background: linear-gradient(135deg, rgba(75,0,130,0.04) 0%, rgba(0,191,255,0.06) 100%);
      border: 1px solid rgba(75,0,130,0.2);
    }
    .icon-circle {
      width: 56px;
      height: 56px;
      background: var(--primary-gradient);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 1.6rem;
      margin-bottom: 18px;
    }
    /* 案例瀑布 */
    .masonry-grid {
      column-count: 3;
      column-gap: 24px;
    }
    @media (max-width: 992px) {
      .masonry-grid {
        column-count: 2;
      }
    }
    @media (max-width: 768px) {
      .masonry-grid {
        column-count: 1;
      }
    }
    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      background: white;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      overflow: hidden;
      transition: 0.3s;
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      height: 160px;
      background-size: cover;
      background-position: center;
    }
    .tag-chip {
      border: 1px solid var(--accent-amber);
      color: var(--accent-amber);
      background: transparent;
      border-radius: 20px;
      padding: 2px 12px;
      font-size: 0.8rem;
      font-weight: 600;
    }
    /* FAQ */
    .accordion-button:not(.collapsed) {
      background-color: #FAF9FC;
      color: #4B0082;
      box-shadow: none;
      border-left: 3px solid #4B0082;
    }
    .accordion-button {
      font-weight: 600;
      background: white;
      border-radius: 12px;
    }
    .accordion-item {
      border: none;
      margin-bottom: 12px;
    }
    /* 表单 */
    .form-control {
      border-radius: 12px;
      border: 1px solid #dcdae5;
      padding: 12px 16px;
    }
    .form-control:focus {
      border-color: #00BFFF;
      box-shadow: 0 0 0 0.2rem rgba(0,191,255,0.25);
    }
    .footer-dark {
      background: #1A1A2E;
      color: #c4c4d4;
      padding: 60px 0 20px;
    }
    .footer-dark a:hover {
      color: #00BFFF;
    }
    @media (max-width: 768px) {
      .hero-section .row {
        flex-direction: column;
      }
      .chip-nav-container {
        flex-wrap: nowrap;
        overflow-x: auto;
        padding-bottom: 8px;
      }
      h1 {
        font-size: 2.2rem;
      }
    }