/* roulang page: index */
:root {
      --primary-deep: #0A0E27;
      --accent-cyan: #00F0FF;
      --accent-pink: #FF3366;
      --bg-light: #F0F2F5;
      --text-white: #FFFFFF;
      --text-dark: #1A1A2E;
      --text-gray: #6B7280;
      --card-dark: #141832;
      --card-light: #FFFFFF;
      --gradient-btn: linear-gradient(135deg, #00F0FF, #0088CC);
      --border-radius-card: 16px;
      --border-radius-btn: 8px;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.1);
      --shadow-glow: 0 12px 30px rgba(0, 240, 255, 0.15);
      --font-heading: 'Montserrat', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --max-width: 1280px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-body);
      background-color: var(--primary-deep);
      color: var(--text-white);
      line-height: 1.4;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    img {
      max-width: 100%;
      display: block;
    }
    button, .btn {
      cursor: pointer;
      font-family: var(--font-body);
      border: none;
      background: none;
    }
    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10, 14, 39, 0.8);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid rgba(0, 240, 255, 0.15);
      padding: 12px 0;
      transition: background 0.3s;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--accent-cyan);
      letter-spacing: -0.5px;
    }
    .logo i {
      font-size: 1.8rem;
      color: var(--accent-cyan);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
    }
    .nav-links a {
      color: var(--text-white);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 4px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-cyan);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent-cyan);
    }
    .nav-actions {
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .search-icon, .user-icon {
      color: var(--text-white);
      font-size: 1.2rem;
      background: none;
      border: none;
      cursor: pointer;
    }
    .btn-outline-nav {
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      background: transparent;
      padding: 8px 18px;
      border-radius: var(--border-radius-btn);
      font-weight: 600;
      font-size: 0.9rem;
      transition: all 0.3s;
    }
    .btn-outline-nav:hover {
      background: var(--accent-cyan);
      color: var(--primary-deep);
    }
    .btn-primary-nav {
      background: var(--gradient-btn);
      color: white;
      padding: 8px 22px;
      border-radius: var(--border-radius-btn);
      font-weight: 600;
      font-size: 0.9rem;
      transition: all 0.3s;
      border: none;
      box-shadow: 0 0 15px rgba(0,240,255,0.3);
    }
    .btn-primary-nav:hover {
      box-shadow: 0 0 25px rgba(0,240,255,0.6);
      transform: translateY(-1px);
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      color: white;
      font-size: 1.8rem;
    }
    /* 首屏 */
    #hero {
      padding: 120px 0 80px;
      background: radial-gradient(circle at 20% 30%, #1a1f3a, var(--primary-deep) 80%);
      position: relative;
      overflow: hidden;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 55% 45%;
      gap: 40px;
      align-items: center;
    }
    .hero-left h1 {
      font-family: var(--font-heading);
      font-size: 56px;
      line-height: 1.2;
      font-weight: 800;
      letter-spacing: -0.5px;
      margin-bottom: 24px;
      color: white;
    }
    .hero-left h1 span {
      color: var(--accent-cyan);
    }
    .hero-sub {
      font-size: 1.2rem;
      color: #ccd6f0;
      margin-bottom: 36px;
      line-height: 1.6;
      max-width: 90%;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--gradient-btn);
      color: white;
      padding: 14px 36px;
      border-radius: var(--border-radius-btn);
      font-weight: 700;
      font-size: 1rem;
      transition: all 0.3s;
      box-shadow: 0 0 20px rgba(0,240,255,0.3);
      border: none;
    }
    .btn-primary:hover {
      box-shadow: 0 0 30px rgba(0,240,255,0.6);
      transform: translateY(-2px);
    }
    .btn-ghost {
      border: 2px solid var(--accent-cyan);
      color: var(--accent-cyan);
      background: transparent;
      padding: 14px 36px;
      border-radius: var(--border-radius-btn);
      font-weight: 700;
      font-size: 1rem;
      transition: all 0.3s;
    }
    .btn-ghost:hover {
      background: var(--accent-cyan);
      color: var(--primary-deep);
    }
    .hero-right {
      position: relative;
      display: flex;
      justify-content: center;
      align-items: center;
      min-height: 380px;
    }
    .hero-art {
      width: 100%;
      max-width: 500px;
      border-radius: 24px;
      box-shadow: 0 0 40px rgba(0,240,255,0.25);
    }
    /* 亮点数据 */
    #highlights {
      background: var(--primary-deep);
      padding: 60px 0;
      border-top: 1px solid rgba(0,240,255,0.1);
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }
    .stat-item .stat-number {
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--accent-cyan);
      display: block;
      line-height: 1.2;
    }
    .stat-item .stat-label {
      color: #b0b8d0;
      font-size: 1rem;
      margin-top: 8px;
    }
    /* 通用section标题 */
    .section-title {
      font-family: var(--font-heading);
      font-size: 40px;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--text-dark);
    }
    .section-sub {
      color: var(--text-gray);
      margin-bottom: 48px;
      font-size: 1.1rem;
    }
    .bg-light-section {
      background: var(--bg-light);
      color: var(--text-dark);
      padding: 80px 0;
    }
    .bg-dark-section {
      background: var(--primary-deep);
      padding: 80px 0;
    }
    /* 优势卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .advantage-card {
      background: var(--card-dark);
      border-radius: var(--border-radius-card);
      padding: 32px;
      transition: all 0.3s;
      border: 1px solid rgba(0,240,255,0.1);
    }
    .advantage-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-glow);
      border-color: var(--accent-cyan);
    }
    .advantage-icon {
      font-size: 2.2rem;
      color: var(--accent-cyan);
      margin-bottom: 20px;
    }
    .advantage-card h3 {
      font-size: 1.5rem;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .advantage-card p {
      color: #b0b8d0;
      line-height: 1.6;
    }
    /* 瀑布流案例 */
    .masonry-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--card-dark);
      border-radius: var(--border-radius-card);
      overflow: hidden;
      transition: all 0.3s;
      border: 1px solid rgba(0,240,255,0.1);
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 20px 35px rgba(0,240,255,0.2);
    }
    .case-img {
      width: 100%;
      height: 200px;
      object-fit: cover;
      display: block;
    }
    .case-info {
      padding: 20px;
    }
    .case-tag {
      background: rgba(255,51,102,0.15);
      color: var(--accent-pink);
      font-size: 0.8rem;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 10px;
    }
    .case-card h4 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 8px;
    }
    /* 对比卡 */
    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      margin-top: 20px;
    }
    .compare-card {
      padding: 32px;
      border-radius: var(--border-radius-card);
      background: white;
      box-shadow: 0 8px 24px rgba(0,0,0,0.05);
    }
    .compare-left {
      border: 1px solid #e0e0e0;
    }
    .compare-right {
      border: 2px solid var(--accent-cyan);
      background: #f0fcff;
      box-shadow: 0 0 25px rgba(0,240,255,0.2);
    }
    .compare-item {
      display: flex;
      justify-content: space-between;
      padding: 12px 0;
      border-bottom: 1px solid #eee;
    }
    /* FAQ */
    .faq-layout {
      display: grid;
      grid-template-columns: 1fr 1.5fr;
      gap: 40px;
      align-items: start;
    }
    .accordion-item {
      border-bottom: 1px solid #e0e0e0;
      padding: 16px 0;
    }
    .accordion-question {
      font-weight: 600;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      color: var(--text-dark);
    }
    .accordion-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: #4b5563;
      margin-top: 8px;
    }
    /* CTA */
    #cta {
      background: radial-gradient(circle at 50% 0%, #1e2545, #0A0E27);
      padding: 80px 0;
      text-align: center;
    }
    /* 页脚 */
    #footer {
      background: #080b1a;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 1024px) {
      .hero-grid { grid-template-columns: 1fr; }
      .cards-grid, .masonry-grid { grid-template-columns: repeat(2,1fr); }
      .stats-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links, .nav-actions .btn-outline-nav, .nav-actions .btn-primary-nav { display: none; }
      .hamburger { display: block; }
      .hero-left h1 { font-size: 36px; }
      .cards-grid, .masonry-grid, .compare-grid, .faq-layout, .footer-grid { grid-template-columns: 1fr; }
      .section-title { font-size: 28px; }
    }