/* roulang page: index */
:root {
      --primary-dark: #0F0F0F;
      --accent-purple: #8B5CF6;
      --accent-purple-hover: #7C3AED;
      --accent-teal: #2DD4BF;
      --white: #FFFFFF;
      --light-bg: #F3F4F6;
      --gray-mid: #9CA3AF;
      --card-dark: #1A1A1A;
      --border-light: #E5E7EB;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --radius-lg: 16px;
      --radius-pill: 50px;
      --shadow-light: 0 4px 20px rgba(0,0,0,0.08);
      --shadow-dark: 0 4px 20px rgba(0,0,0,0.4);
      --transition-smooth: 0.3s ease;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: var(--font-body);
      background-color: var(--primary-dark);
      color: var(--white);
      line-height: 1.7;
      overflow-x: hidden;
    }
    h1, h2, h3, h4, .display-font {
      font-family: var(--font-heading);
      font-weight: 700;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container-custom {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 悬浮胶囊导航 */
    .navbar-custom {
      position: fixed;
      top: 20px;
      left: 50%;
      transform: translateX(-50%);
      width: auto;
      max-width: 90%;
      background: rgba(15, 15, 15, 0.85);
      backdrop-filter: blur(10px);
      -webkit-backdrop-filter: blur(10px);
      border-radius: var(--radius-pill);
      padding: 8px 24px;
      z-index: 1000;
      border: 1px solid rgba(255,255,255,0.05);
      transition: background 0.3s;
    }
    .navbar-custom .nav-link {
      color: var(--white);
      font-weight: 500;
      margin: 0 8px;
      padding: 8px 12px;
      border-radius: 30px;
      transition: color 0.3s;
      font-size: 0.95rem;
    }
    .navbar-custom .nav-link:hover,
    .navbar-custom .nav-link.active-nav {
      color: var(--accent-purple);
    }
    .navbar-custom .active-indicator {
      color: var(--accent-teal);
      font-weight: 600;
    }
    .logo-text {
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.4rem;
      letter-spacing: -0.5px;
      background: linear-gradient(135deg, var(--accent-purple) 30%, var(--accent-teal) 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-right: 16px;
    }
    .btn-capsule {
      border-radius: var(--radius-pill);
      padding: 10px 28px;
      font-weight: 600;
      transition: all 0.3s ease;
      font-size: 0.95rem;
    }
    .btn-primary-custom {
      background: var(--accent-purple);
      border: none;
      color: white;
    }
    .btn-primary-custom:hover {
      background: var(--accent-purple-hover);
      box-shadow: 0 0 16px rgba(139, 92, 246, 0.6);
      color: white;
    }
    .btn-outline-teal {
      background: transparent;
      border: 2px solid var(--accent-teal);
      color: var(--accent-teal);
    }
    .btn-outline-teal:hover {
      background: var(--accent-teal);
      color: var(--primary-dark);
      border-color: var(--accent-teal);
    }
    /* Hero */
    .hero-section {
      padding: 160px 0 100px;
      background: radial-gradient(circle at 80% 20%, rgba(139,92,246,0.08) 0%, rgba(15,15,15,0) 60%);
    }
    .hero-title {
      font-size: 3.5rem;
      line-height: 1.2;
      letter-spacing: -0.02em;
      font-weight: 700;
    }
    .hero-highlight {
      background: linear-gradient(135deg, var(--accent-purple) 20%, var(--accent-teal) 90%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero-image-wrapper {
      position: relative;
      border-radius: 24px;
      overflow: hidden;
      background: #1A1A1A;
      box-shadow: var(--shadow-dark);
    }
    .hero-image-wrapper img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    .hero-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 50%;
      background: linear-gradient(to top, rgba(15,15,15,0.9), transparent);
    }
    /* 板块通用 */
    .section-padding {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.5rem;
      font-weight: 600;
      margin-bottom: 1rem;
      color: var(--white);
    }
    .section-subtitle {
      color: var(--gray-mid);
      font-size: 1.1rem;
    }
    .bg-dark-card {
      background: var(--card-dark);
    }
    .card-custom {
      border-radius: var(--radius-lg);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
    }
    /* 亮点卡片 */
    .highlight-card {
      background: var(--card-dark);
      border-radius: var(--radius-lg);
      padding: 32px 24px;
      border-left: 4px solid var(--accent-teal);
      transition: all 0.3s ease;
    }
    .highlight-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-dark);
    }
    .big-number {
      font-size: 3rem;
      font-weight: 700;
      color: var(--accent-teal);
      line-height: 1.2;
    }
    /* 案例卡片 */
    .case-card {
      background: var(--white);
      color: var(--primary-dark);
      border-radius: 12px;
      overflow: hidden;
      border: 1px solid var(--border-light);
      transition: all 0.3s ease;
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 12px 30px rgba(0,0,0,0.2);
    }
    .case-card img {
      transition: transform 0.4s ease;
      aspect-ratio: 16/9;
      object-fit: cover;
    }
    .case-card:hover img {
      transform: scale(1.04);
    }
    .badge-purple {
      background: var(--accent-purple);
      color: white;
      border-radius: 30px;
      padding: 4px 14px;
      font-size: 0.8rem;
      font-weight: 600;
    }
    /* 方案对比 */
    .compare-card {
      background: var(--card-dark);
      border-radius: var(--radius-lg);
      padding: 32px;
      border: 1px solid transparent;
      transition: all 0.3s;
    }
    .compare-card.popular {
      border: 2px solid var(--accent-purple);
      position: relative;
      box-shadow: 0 0 20px rgba(139,92,246,0.25);
    }
    .popular-badge {
      background: var(--accent-teal);
      color: var(--primary-dark);
      font-weight: 700;
      padding: 6px 16px;
      border-radius: 30px;
      position: absolute;
      top: -14px;
      left: 50%;
      transform: translateX(-50%);
      font-size: 0.9rem;
    }
    /* FAQ */
    .accordion-button {
      background: transparent;
      color: white;
      font-weight: 600;
      border: none;
      box-shadow: none;
      padding: 20px 0;
      font-size: 1.1rem;
    }
    .accordion-button:not(.collapsed) {
      background: transparent;
      color: var(--accent-teal);
    }
    .accordion-button::after {
      filter: brightness(0) invert(1);
    }
    .accordion-item {
      background: transparent;
      border: none;
      border-bottom: 1px solid rgba(255,255,255,0.1);
    }
    /* CTA 横幅 */
    .cta-full {
      background: var(--primary-dark);
      border-top: 1px solid rgba(255,255,255,0.05);
    }
    /* 表单 */
    .form-underline {
      border: none;
      border-bottom: 2px solid #D1D5DB;
      border-radius: 0;
      padding: 12px 4px;
      background: transparent;
      color: white;
      transition: border-color 0.3s;
    }
    .form-underline:focus {
      border-color: var(--accent-purple);
      box-shadow: none;
      outline: none;
    }
    .footer-link:hover {
      color: var(--accent-teal);
    }
    @media (max-width: 768px) {
      .hero-title {
        font-size: 2.5rem;
      }
      .section-title {
        font-size: 2rem;
      }
      .navbar-custom {
        padding: 8px 16px;
      }
    }