/* roulang page: index */
:root {
      --primary: #0A6EFF;
      --primary-dark: #0857CC;
      --accent: #FF6B35;
      --accent-glow: rgba(255, 107, 53, 0.3);
      --bg: #F8FAFC;
      --surface: #FFFFFF;
      --dark-bg: #1E293B;
      --text-main: #0F172A;
      --text-secondary: #475569;
      --text-body: #334155;
      --text-light: #CBD5E1;
      --border: rgba(0,0,0,0.05);
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(10,110,255,0.08);
      --shadow-lg: 0 12px 32px rgba(10,110,255,0.12);
      --radius-lg: 20px;
      --radius-md: 14px;
      --radius-sm: 10px;
      --radius-btn: 30px;
      --transition: 0.25s cubic-bezier(0.2, 0.0, 0, 1.0);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", "Inter", Arial, sans-serif;
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      transition: background 0.3s ease, box-shadow 0.3s ease, padding 0.3s;
      padding: 16px 0;
      background: transparent;
    }
    .nav.scrolled {
      background: #FFFFFF;
      box-shadow: 0 6px 20px rgba(0,0,0,0.04);
      padding: 10px 0;
    }
    .nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    .logo {
      font-weight: 700;
      font-size: 1.8rem;
      letter-spacing: -0.5px;
      color: white;
      display: flex;
      align-items: center;
      gap: 6px;
      transition: color 0.3s;
    }
    .nav.scrolled .logo {
      color: var(--text-main);
    }
    .logo-icon {
      font-size: 2rem;
      line-height: 1;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      color: rgba(255,255,255,0.9);
      font-size: 1rem;
      position: relative;
      padding: 4px 0;
    }
    .nav.scrolled .nav-links a {
      color: var(--text-main);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: white;
      border-radius: 4px;
      transition: 0.3s;
    }
    .nav.scrolled .hamburger span {
      background: var(--text-main);
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(10px);
      display: none;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 36px;
      z-index: 99;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.3s;
    }
    .mobile-menu.open {
      display: flex;
      opacity: 1;
      pointer-events: auto;
    }
    .mobile-menu a {
      font-size: 1.8rem;
      font-weight: 600;
      color: var(--text-main);
    }
    /* Hero */
    .hero {
      padding: 160px 0 100px;
      background: radial-gradient(circle at 85% 20%, rgba(10,110,255,0.12) 0%, transparent 45%);
      display: flex;
      align-items: center;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero-left h1 {
      font-size: 3.4rem;
      font-weight: 700;
      line-height: 1.2;
      color: var(--text-main);
      margin-bottom: 24px;
    }
    .hero-left p {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 36px;
      max-width: 500px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      box-shadow: 0 8px 18px rgba(10,110,255,0.3);
      border: none;
      cursor: pointer;
      transition: var(--transition);
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 12px 24px rgba(10,110,255,0.4);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition);
      display: inline-block;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    .hero-right img {
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-lg);
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    /* 板块通用 */
    section {
      padding: 90px 0;
    }
    .section-title {
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-sub {
      color: var(--text-secondary);
      text-align: center;
      max-width: 640px;
      margin: 0 auto 56px;
      font-size: 1.1rem;
    }
    /* 亮点网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .feature-card {
      background: var(--surface);
      padding: 36px 24px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: var(--transition);
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: 0 8px 24px rgba(10,110,255,0.12);
    }
    .feature-icon {
      font-size: 2.8rem;
      margin-bottom: 18px;
    }
    .feature-card h3 {
      font-weight: 600;
      color: #1E293B;
      margin-bottom: 8px;
    }
    /* 案例瀑布 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
      gap: 28px;
    }
    .case-card {
      background: var(--surface);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
    }
    .case-img {
      position: relative;
      height: 200px;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .case-overlay {
      position: absolute;
      inset: 0;
      background: rgba(10,110,255,0.7);
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      transition: 0.3s;
      color: white;
      font-weight: 600;
    }
    .case-card:hover .case-overlay {
      opacity: 1;
    }
    .case-info {
      padding: 20px;
    }
    .case-tag {
      background: var(--accent);
      color: white;
      font-size: 0.7rem;
      padding: 4px 10px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 8px;
    }
    /* 对比表 */
    .compare-table {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 10px;
    }
    .plan-card {
      background: var(--surface);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      flex: 1;
      min-width: 240px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border);
      transition: var(--transition);
    }
    .plan-card.recommend {
      border: 2px solid var(--accent);
      position: relative;
      transform: scale(1.02);
    }
    .badge-hot {
      background: var(--accent);
      color: white;
      font-size: 0.8rem;
      padding: 4px 12px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      right: 20px;
    }
    .plan-name {
      font-weight: 700;
      font-size: 1.5rem;
      margin-bottom: 20px;
    }
    .plan-item {
      display: flex;
      justify-content: space-between;
      padding: 12px 0;
      border-bottom: 1px solid #f1f5f9;
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: var(--surface);
      border-radius: var(--radius-sm);
      margin-bottom: 16px;
      box-shadow: var(--shadow-sm);
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: #F8FAFC;
      padding: 0 24px;
      color: #475569;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px 24px;
    }
    /* CTA横幅 */
    .cta-banner {
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      text-align: center;
      color: white;
      padding: 80px 0;
      border-radius: var(--radius-lg);
    }
    .btn-white {
      background: white;
      color: var(--primary);
      padding: 16px 48px;
      border-radius: 40px;
      font-weight: 700;
      margin-top: 28px;
      display: inline-block;
    }
    /* 页脚 */
    .footer {
      background: var(--dark-bg);
      color: var(--text-light);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .copyright {
      border-top: 1px solid #334155;
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
      font-size: 0.9rem;
    }
    @media (max-width: 1024px) {
      .hero-grid { grid-template-columns: 1fr; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .features-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .hero-left h1 { font-size: 2.5rem; }
      .compare-table { flex-direction: column; }
    }