/* roulang page: index */
/* ----- 设计变量与基础重置 ----- */
    :root {
      --primary-black: #0A0E17;
      --accent-red: #FF4655;
      --highlight-cyan: #00F0FF;
      --neutral-light: #F4F4F7;
      --card-bg: #1A1F2B;
      --text-secondary: #8A8F9C;
      --border-light: rgba(255,255,255,0.08);
      --shadow-card: 0 4px 24px rgba(0,0,0,0.25);
      --shadow-hover: 0 8px 32px rgba(255,70,85,0.15);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-nav: 24px;
      --font-cn: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-en: "Inter", "SF Pro Display", sans-serif;
      --transition-smooth: all 0.25s cubic-bezier(0.2, 0.0, 0, 1.0);
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-cn);
      background-color: var(--primary-black);
      color: #E8ECF1;
      line-height: 1.7;
      font-weight: 400;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    img {
      display: block;
      max-width: 100%;
      height: auto;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }

    button, input, select {
      font-family: inherit;
      border: none;
      outline: none;
      background: transparent;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 工具类 */
    .text-en {
      font-family: var(--font-en);
      letter-spacing: -0.02em;
    }
    .cyan-glow {
      color: var(--highlight-cyan);
    }
    .red-accent {
      color: var(--accent-red);
    }

    /* ----- 浮动 Dock 导航 ----- */
    .dock-nav {
      position: fixed;
      top: 24px;
      left: 50%;
      transform: translateX(-50%);
      width: calc(100% - 40px);
      max-width: 720px;
      background: rgba(10, 14, 23, 0.85);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-radius: var(--radius-nav);
      padding: 8px 20px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      box-shadow: 0 10px 25px -8px rgba(0,0,0,0.7);
      z-index: 1000;
      transition: background 0.3s, box-shadow 0.3s;
      border: 1px solid rgba(255,255,255,0.05);
    }

    .dock-nav.scrolled {
      background: rgba(10, 14, 23, 0.92);
      box-shadow: 0 14px 30px -10px rgba(0,240,255,0.12);
    }

    .nav-logo {
      font-weight: 800;
      font-size: 1.5rem;
      color: var(--accent-red);
      letter-spacing: -0.5px;
      font-family: var(--font-cn);
      text-shadow: 0 0 8px rgba(255,70,85,0.4);
      white-space: nowrap;
    }

    .nav-links {
      display: flex;
      gap: 1.8rem;
      align-items: center;
      font-size: 0.9rem;
      font-weight: 500;
      color: var(--text-secondary);
      list-style: none;
    }

    .nav-links a {
      color: var(--text-secondary);
      transition: color 0.2s;
      position: relative;
    }

    .nav-links a:hover {
      color: var(--highlight-cyan);
    }

    .nav-cta {
      background: var(--accent-red);
      color: white;
      padding: 8px 18px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 0.9rem;
      box-shadow: 0 0 12px rgba(255,70,85,0.5);
      transition: box-shadow 0.25s, background 0.2s;
      white-space: nowrap;
    }

    .nav-cta:hover {
      box-shadow: 0 0 22px rgba(255,70,85,0.8);
      background: #ff5a66;
      color: white;
    }

    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: var(--highlight-cyan);
      cursor: pointer;
    }

    /* 移动端导航抽屉 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(10,14,23,0.98);
      backdrop-filter: blur(20px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2.5rem;
      z-index: 999;
      transform: translateY(-100%);
      transition: transform 0.4s ease;
    }
    .mobile-menu.open {
      transform: translateY(0);
    }
    .mobile-menu a {
      font-size: 1.8rem;
      font-weight: 700;
      color: white;
    }
    .mobile-menu .close-btn {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 2.4rem;
      color: var(--highlight-cyan);
    }

    /* ----- 通用区块标题 ----- */
    .section-title {
      font-size: 2.25rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      margin-bottom: 0.75rem;
      color: white;
    }
    .section-sub {
      color: var(--text-secondary);
      font-size: 1.1rem;
      max-width: 600px;
    }

    /* ----- Hero 双栏 ----- */
    .hero-grid {
      display: grid;
      grid-template-columns: 55% 45%;
      align-items: center;
      min-height: 100vh;
      padding-top: 100px;
      gap: 3rem;
    }
    .hero-left h1 {
      font-size: 3rem;
      font-weight: 800;
      line-height: 1.2;
      background: linear-gradient(135deg, #FF4655 0%, #FF8A80 80%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 1.2rem;
      letter-spacing: -0.02em;
    }
    .hero-sub {
      font-size: 1.15rem;
      color: var(--text-secondary);
      margin-bottom: 2rem;
    }
    .hero-actions {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
      margin-bottom: 2.5rem;
    }
    .btn-primary {
      background: var(--accent-red);
      color: white;
      padding: 14px 30px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      box-shadow: 0 0 14px rgba(255,70,85,0.5);
      transition: box-shadow 0.25s;
    }
    .btn-primary:hover {
      box-shadow: 0 0 28px rgba(255,70,85,0.9);
    }
    .btn-outline {
      border: 1.5px solid var(--highlight-cyan);
      color: var(--highlight-cyan);
      padding: 14px 30px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      background: transparent;
      transition: 0.25s;
    }
    .btn-outline:hover {
      background: rgba(0,240,255,0.1);
      border-color: white;
    }
    .stats-row {
      display: flex;
      gap: 2rem;
    }
    .stat-item .stat-num {
      font-size: 2.2rem;
      font-weight: 800;
      color: var(--highlight-cyan);
      font-family: var(--font-en);
    }
    .hero-right {
      position: relative;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
    }
    .hero-right img {
      width: 100%;
    }
    .particle-overlay {
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 20% 30%, rgba(0,240,255,0.1) 0%, transparent 50%);
      pointer-events: none;
    }

    /* 亮点网格 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 3rem;
    }
    .highlight-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 30px 24px;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }
    .highlight-card:hover {
      box-shadow: var(--shadow-hover);
      border: 1px solid rgba(0,240,255,0.25);
    }
    .highlight-icon {
      font-size: 2.8rem;
      color: var(--highlight-cyan);
      margin-bottom: 1.2rem;
    }

    /* 案例瀑布流 */
    .masonry-grid {
      columns: 2;
      column-gap: 24px;
      margin-top: 3rem;
    }
    .case-card {
      break-inside: avoid;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      margin-bottom: 24px;
      overflow: hidden;
      transition: all 0.3s;
    }
    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: 0 12px 28px rgba(255,70,85,0.18);
    }
    .case-img {
      width: 100%;
      transition: transform 0.4s;
    }
    .case-card:hover .case-img {
      transform: scale(1.03);
    }

    /* 对比表 */
    .compare-table {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 2.5rem;
    }
    .plan-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      position: relative;
      transition: 0.25s;
      border: 1px solid transparent;
    }
    .plan-highlight {
      transform: scale(1.03);
      border: 1px solid rgba(0,240,255,0.4);
      box-shadow: 0 0 20px rgba(0,240,255,0.2);
    }
    .badge {
      background: var(--accent-red);
      color: white;
      font-size: 0.75rem;
      padding: 4px 10px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      right: 16px;
    }

    /* FAQ */
    .faq-item {
      background: var(--card-bg);
      border-radius: 8px;
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      padding: 16px;
      font-weight: 700;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: rgba(0,0,0,0.2);
      padding: 0 16px;
    }

    /* CTA 表单 */
    .cta-form {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      justify-content: center;
      margin-top: 2rem;
    }
    .cta-form input, .cta-form select {
      background: var(--card-bg);
      border: 1px solid #2A2F3B;
      padding: 14px 18px;
      border-radius: 8px;
      color: white;
      min-width: 200px;
    }
    .submit-glow {
      background: var(--accent-red);
      padding: 14px 36px;
      font-weight: 700;
      border-radius: 8px;
      cursor: pointer;
      box-shadow: 0 0 10px #FF4655;
    }

    footer {
      background: #05070A;
      padding: 2rem 0;
      color: var(--text-secondary);
    }

    @media (max-width: 768px) {
      .hero-grid { grid-template-columns: 1fr; }
      .nav-links { display: none; }
      .hamburger { display: block; }
      .highlights-grid, .compare-table { grid-template-columns: 1fr; }
      .masonry-grid { columns: 1; }
      .plan-highlight { transform: none; }
    }