/* roulang page: index */
:root {
      --bs-body-bg: #FAF8F5;
      --bs-body-color: #4A4A4A;
      --bs-primary: #2E4A3A;
      --bs-primary-rgb: 46, 74, 58;
      --bs-border-radius: 8px;
      --bs-btn-border-radius: 8px;
      --color-deep: #1A1A1A;
      --color-gold: #C5A56B;
      --color-green: #2E4A3A;
      --color-warm-bg: #FAF8F5;
      --color-white: #FFFFFF;
      --color-text: #4A4A4A;
      --color-muted: #7A7A7A;
      --color-border: #E4E0D9;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --font-serif: 'Noto Serif SC', 'Times New Roman', serif;
      --font-sans: 'Noto Sans SC', 'Helvetica Neue', Arial, sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--color-warm-bg);
      color: var(--color-text);
      font-weight: 400;
      font-size: 16px;
      line-height: 1.8;
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4, .font-serif {
      font-family: var(--font-serif);
      font-weight: 700;
    }
    .section-title {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 32px;
      color: var(--color-deep);
      margin-bottom: 1rem;
    }
    .section-subtitle {
      color: var(--color-muted);
      font-size: 18px;
      margin-bottom: 2.5rem;
    }
    .btn-primary {
      background-color: var(--color-green);
      border-color: var(--color-green);
      font-weight: 500;
      padding: 0.7rem 1.8rem;
      letter-spacing: 0.5px;
      transition: all 0.25s ease;
    }
    .btn-primary:hover {
      background-color: #1f3528;
      border-color: #1f3528;
      transform: translateY(-2px);
      box-shadow: var(--shadow-hover);
    }
    .btn-outline-primary {
      border-color: var(--color-green);
      color: var(--color-green);
      font-weight: 500;
      padding: 0.7rem 1.8rem;
      transition: all 0.25s ease;
    }
    .btn-outline-primary:hover {
      background-color: var(--color-green);
      border-color: var(--color-green);
      color: white;
      transform: translateY(-2px);
    }
    /* 导航栏 SaaS 风格 */
    .navbar {
      background: rgba(250, 248, 245, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,0,0,0.04);
      padding: 1rem 0;
      transition: box-shadow 0.3s;
    }
    .navbar.scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }
    .navbar-brand {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 1.8rem;
      color: var(--color-deep) !important;
      letter-spacing: 1px;
    }
    .navbar-brand span {
      color: var(--color-gold);
    }
    .nav-link {
      color: var(--color-deep) !important;
      font-size: 15px;
      font-weight: 400;
      margin: 0 0.5rem;
      position: relative;
      transition: 0.2s;
    }
    .nav-link:hover {
      color: var(--color-green) !important;
    }
    .nav-link.active {
      font-weight: 600;
      color: var(--color-green) !important;
    }
    .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background-color: var(--color-green);
    }
    .search-btn {
      background: transparent;
      border: none;
      font-size: 1.3rem;
      color: var(--color-deep);
      margin-right: 1.2rem;
    }
    .search-btn:hover {
      color: var(--color-green);
    }
    .navbar .btn-primary {
      background-color: var(--color-green);
      border: none;
      padding: 0.5rem 1.5rem;
      font-weight: 500;
    }
    /* Hero */
    .hero {
      padding: 8rem 0 5rem;
      background-color: var(--color-warm-bg);
    }
    .hero h1 {
      font-size: 48px;
      font-weight: 700;
      color: var(--color-deep);
      line-height: 1.3;
      margin-bottom: 1.5rem;
    }
    .hero .lead {
      font-size: 18px;
      color: var(--color-muted);
      margin-bottom: 2rem;
    }
    .hero-img {
      border-radius: 20px;
      max-height: 380px;
      object-fit: cover;
      width: 100%;
      box-shadow: 0 20px 40px rgba(0,0,0,0.05);
    }
    /* 卡片通用 */
    .card-custom {
      background: var(--color-white);
      border: none;
      border-radius: 12px;
      box-shadow: var(--shadow-card);
      transition: all 0.25s ease;
    }
    .card-custom:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .icon-box {
      font-size: 2rem;
      color: var(--color-green);
      margin-bottom: 1rem;
    }
    /* 案例瀑布流 */
    .case-card {
      background: var(--color-white);
      border-radius: 12px;
      overflow: hidden;
      box-shadow: var(--shadow-card);
      margin-bottom: 40px;
    }
    .case-img {
      width: 100%;
      height: 260px;
      object-fit: cover;
      border-radius: 12px;
    }
    .tag {
      background: transparent;
      border: 1px solid var(--color-green);
      color: var(--color-green);
      padding: 0.2rem 1rem;
      border-radius: 20px;
      font-size: 13px;
      display: inline-block;
    }
    /* 方案卡片 */
    .plan-card {
      background: white;
      border-radius: 16px;
      padding: 2rem;
      box-shadow: var(--shadow-card);
      height: 100%;
      display: flex;
      flex-direction: column;
    }
    .plan-highlight {
      border-top: 5px solid var(--color-green);
      background: #F6F4EF;
    }
    /* 流程步骤 */
    .step-circle {
      width: 48px;
      height: 48px;
      background: var(--color-green);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 20px;
      margin-bottom: 1rem;
    }
    .step-line {
      border-left: 2px dashed #ccc;
      height: 40px;
      margin: 0 auto;
    }
    /* FAQ */
    .accordion-button:not(.collapsed) {
      background-color: #F6F4EF;
      color: var(--color-deep);
      box-shadow: none;
    }
    .accordion-button:focus {
      border-color: var(--color-green);
      box-shadow: 0 0 0 0.2rem rgba(46,74,58,0.2);
    }
    /* CTA 横幅 */
    .cta-banner {
      background-color: var(--color-green);
      border-radius: 20px;
      padding: 4rem 2rem;
      color: white;
    }
    /* 页脚 */
    footer {
      background: var(--color-deep);
      color: #B0B0B0;
    }
    footer a {
      color: #B0B0B0;
      text-decoration: none;
    }
    footer a:hover {
      color: var(--color-gold);
    }
    @media (max-width: 768px) {
      .hero h1 {
        font-size: 36px;
      }
      .section-title {
        font-size: 28px;
      }
      .navbar-brand {
        font-size: 1.5rem;
      }
    }