/* roulang page: index */
:root {
      --primary: #E8452D;
      --primary-dark: #C0392B;
      --secondary: #1A1A1A;
      --warm-bg: #F5F0EB;
      --accent: #FFB800;
      --success: #2ECC71;
      --white: #FFFFFF;
      --light-gray: #F8F9FA;
      --text-muted: #6C757D;
      --border-radius-card: 12px;
      --border-radius-btn: 8px;
      --border-radius-input: 6px;
      --shadow-sm: 0 2px 16px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --transition: 0.25s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', system-ui, -apple-system, sans-serif;
      background-color: var(--warm-bg);
      color: var(--secondary);
      line-height: 1.7;
      font-size: 15px;
      margin: 0;
      padding-top: 64px;
    }
    h1, h2, h3, h4, .h1, .h2, .h3 {
      font-weight: 700;
      letter-spacing: -0.5px;
    }
    h1 {
      font-size: 48px;
      line-height: 1.2;
    }
    h2 {
      font-size: 32px;
      margin-bottom: 1rem;
    }
    h3 {
      font-size: 20px;
    }
    .section-padding {
      padding: 80px 0;
    }
    @media (max-width: 768px) {
      h1 {
        font-size: 36px;
      }
      h2 {
        font-size: 28px;
      }
      .section-padding {
        padding: 60px 0;
      }
    }
    /* 导航栏 */
    .navbar-custom {
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(8px);
      height: 64px;
      box-shadow: 0 2px 12px rgba(0,0,0,0.02);
      transition: background 0.3s, box-shadow 0.3s;
    }
    .navbar-custom.scrolled {
      background: #fff;
      box-shadow: 0 4px 20px rgba(0,0,0,0.05);
    }
    .navbar-brand {
      font-weight: 800;
      font-size: 1.5rem;
      color: var(--primary) !important;
      letter-spacing: -0.5px;
    }
    .nav-link {
      color: var(--secondary) !important;
      font-size: 0.9rem;
      font-weight: 500;
      margin: 0 0.5rem;
      position: relative;
      transition: color 0.2s;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary) !important;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s;
    }
    .nav-link:hover::after, .nav-link.active::after {
      width: 100%;
    }
    .search-box {
      background: #f1f3f5;
      border-radius: 30px;
      padding: 0.3rem 1rem;
      display: flex;
      align-items: center;
      gap: 0.5rem;
      border: 1px solid transparent;
      transition: all 0.2s;
    }
    .search-box input {
      border: none;
      background: transparent;
      outline: none;
      font-size: 0.85rem;
      width: 120px;
    }
    .search-box:focus-within {
      border-color: var(--primary);
      background: white;
      box-shadow: 0 0 0 2px rgba(232,69,45,0.1);
    }
    .btn-primary-custom {
      background: var(--accent);
      border: none;
      color: var(--secondary);
      font-weight: 600;
      padding: 8px 18px;
      border-radius: 30px;
      font-size: 0.9rem;
      transition: 0.2s;
    }
    .btn-primary-custom:hover {
      background: #e6a800;
      color: #000;
    }
    .navbar-toggler {
      border: none;
    }
    @media (max-width: 992px) {
      .navbar-collapse {
        background: white;
        padding: 1rem;
        border-radius: 12px;
        margin-top: 0.5rem;
        box-shadow: var(--shadow-hover);
      }
    }
    /* 按钮系统 */
    .btn-brand {
      background: var(--primary);
      color: white;
      border-radius: var(--border-radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      border: none;
      transition: all 0.25s;
      display: inline-block;
      text-decoration: none;
    }
    .btn-brand:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(232,69,45,0.3);
      color: white;
    }
    .btn-outline-brand {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
      border-radius: var(--border-radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      transition: all 0.25s;
    }
    .btn-outline-brand:hover {
      background: rgba(232,69,45,0.05);
      color: var(--primary-dark);
    }
    /* 卡片 */
    .card-custom {
      background: white;
      border-radius: var(--border-radius-card);
      box-shadow: var(--shadow-sm);
      transition: all 0.25s;
      border: none;
      height: 100%;
    }
    .card-custom:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    /* Hero */
    .hero-visual {
      background: linear-gradient(135deg, #f0e9e3 0%, #e8dfd8 100%);
      border-radius: 24px;
      overflow: hidden;
      position: relative;
    }
    .hero-img {
      width: 100%;
      height: auto;
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    }
    /* 亮点网格 */
    .grid-item {
      background: white;
      border-radius: var(--border-radius-card);
      padding: 2rem;
      box-shadow: var(--shadow-sm);
      transition: all 0.25s;
    }
    .grid-item:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .grid-item.wide {
      grid-column: span 2;
    }
    @media (max-width: 768px) {
      .grid-item.wide {
        grid-column: span 1;
      }
    }
    /* 案例瀑布流 */
    .masonry-grid {
      column-count: 3;
      column-gap: 24px;
    }
    .masonry-item {
      break-inside: avoid;
      margin-bottom: 24px;
      background: white;
      border-radius: var(--border-radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: 0.25s;
    }
    .masonry-item:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .masonry-item img {
      width: 100%;
      display: block;
      transition: transform 0.3s;
    }
    .masonry-item:hover img {
      transform: scale(1.03);
    }
    @media (max-width: 992px) {
      .masonry-grid {
        column-count: 2;
      }
    }
    @media (max-width: 576px) {
      .masonry-grid {
        column-count: 1;
      }
    }
    /* 对比区 */
    .compare-check {
      color: var(--success);
      font-weight: bold;
      margin-right: 8px;
    }
    .compare-cross {
      color: #ccc;
      margin-right: 8px;
    }
    .compare-highlight {
      background: rgba(232,69,45,0.04);
      border-left: 4px solid var(--primary);
      padding-left: 16px;
    }
    /* FAQ */
    .accordion-button:not(.collapsed) {
      color: var(--primary);
      background-color: white;
      box-shadow: none;
      font-weight: 600;
    }
    .accordion-button:focus {
      border-color: transparent;
      box-shadow: 0 0 0 2px rgba(232,69,45,0.2);
    }
    .accordion-item {
      border: none;
      margin-bottom: 12px;
      border-radius: var(--border-radius-card) !important;
      overflow: hidden;
      background: white;
    }
    /* CTA 横幅 */
    .cta-banner {
      background: var(--secondary);
      padding: 80px 0;
    }
    /* 页脚 */
    .footer {
      background: var(--secondary);
      color: rgba(255,255,255,0.7);
      font-size: 0.9rem;
    }
    .footer a {
      color: rgba(255,255,255,0.7);
      text-decoration: none;
      transition: 0.2s;
    }
    .footer a:hover {
      color: var(--primary);
    }
    .footer h5 {
      color: white;
      font-weight: 600;
      margin-bottom: 1rem;
    }
    /* 动画 */
    .fade-up {
      opacity: 0;
      transform: translateY(20px);
      transition: opacity 0.6s ease, transform 0.6s ease;
    }
    .fade-up.visible {
      opacity: 1;
      transform: translateY(0);
    }