/* roulang page: index */
:root {
      --primary: #FF3B0F;
      --primary-dark: #e6330a;
      --accent: #00E5FF;
      --dark-bg: #0F1A2E;
      --darker-bg: #0A0E17;
      --light-bg: #F4F6F9;
      --text-dark: #0F1A2E;
      --text-gray: #5A6475;
      --text-light: #FFFFFF;
      --text-light-muted: #B0B8C5;
      --glass-bg: rgba(255, 255, 255, 0.03);
      --glass-border: rgba(255, 255, 255, 0.06);
      --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
      --glow-primary: 0 0 20px rgba(255, 59, 15, 0.5);
      --glow-primary-hover: 0 0 35px rgba(255, 59, 15, 0.8);
      --glow-accent: 0 0 18px rgba(0, 229, 255, 0.4);
      --radius-card: 16px;
      --radius-btn: 40px;
      --radius-img: 12px;
      --transition: 0.3s ease;
      --container-max: 1280px;
      --section-padding: 120px;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      margin: 0;
      background-color: var(--light-bg);
      color: var(--text-dark);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      box-shadow: var(--card-shadow);
      transition: var(--transition);
    }

    .glass-card:hover {
      border-color: rgba(255, 255, 255, 0.12);
      box-shadow: 0 12px 40px rgba(0, 0, 0, 0.5);
    }

    /* 发光按钮 */
    .btn-glow {
      background-color: var(--primary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 14px 36px;
      font-weight: 600;
      font-size: 16px;
      border: none;
      cursor: pointer;
      transition: var(--transition);
      box-shadow: var(--glow-primary);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      letter-spacing: 0.5px;
    }

    .btn-glow:hover {
      box-shadow: var(--glow-primary-hover);
      transform: translateY(-2px);
      background-color: #ff4d1f;
    }

    .btn-outline-glow {
      background: transparent;
      color: var(--accent);
      border: 2px solid var(--accent);
      border-radius: var(--radius-btn);
      padding: 14px 36px;
      font-weight: 600;
      font-size: 16px;
      cursor: pointer;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      letter-spacing: 0.5px;
      box-shadow: 0 0 12px rgba(0, 229, 255, 0.2);
    }

    .btn-outline-glow:hover {
      background: var(--accent);
      color: var(--darker-bg);
      box-shadow: 0 0 28px rgba(0, 229, 255, 0.7);
      transform: translateY(-2px);
    }

    /* 导航 */
    .main-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: rgba(15, 26, 46, 0.8);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.25);
      transition: var(--transition);
    }

    .nav-link {
      color: var(--text-light-muted);
      text-decoration: none;
      font-weight: 500;
      font-size: 15px;
      padding: 8px 12px;
      border-radius: 20px;
      transition: var(--transition);
      position: relative;
    }

    .nav-link:hover,
    .nav-link.active {
      color: var(--accent);
    }

    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%);
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: var(--transition);
    }

    .nav-link:hover::after,
    .nav-link.active::after {
      width: 70%;
    }

    /* 汉堡菜单 */
    .hamburger {
      display: none;
      flex-direction: column;
      cursor: pointer;
      gap: 6px;
    }

    .hamburger span {
      display: block;
      width: 26px;
      height: 2px;
      background: white;
      transition: var(--transition);
    }

    .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;
      justify-content: center;
      padding: 32px;
      transform: translateX(-100%);
      transition: 0.4s ease;
      z-index: 99;
    }

    .mobile-menu.open {
      transform: translateX(0);
    }

    .mobile-menu a {
      color: white;
      font-size: 24px;
      margin: 16px 0;
      text-decoration: none;
      font-weight: 600;
      padding-left: 16px;
      border-left: 4px solid var(--primary);
      transition: 0.2s;
    }

    .mobile-menu a:hover {
      color: var(--accent);
      border-left-color: var(--accent);
    }

    /* 板块间距 */
    section {
      padding: var(--section-padding) 0;
    }

    @media (max-width: 1024px) {
      :root {
        --section-padding: 80px;
      }
    }

    @media (max-width: 768px) {
      :root {
        --section-padding: 60px;
      }
      .hamburger {
        display: flex;
      }
      .desktop-nav-links {
        display: none;
      }
    }

    /* 进度条动画 */
    .progress-bar {
      height: 4px;
      background: rgba(255,255,255,0.1);
      border-radius: 2px;
      margin-top: 12px;
      overflow: hidden;
    }
    .progress-fill {
      height: 100%;
      width: 0%;
      background: var(--accent);
      box-shadow: 0 0 10px var(--accent);
      transition: width 1.5s ease;
    }

    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.08);
      padding: 20px 0;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      padding-left: 16px;
      border-left: 3px solid var(--accent);
      margin-top: 12px;
      color: var(--text-light-muted);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
    }

    /* 粒子背景模拟 */
    .particle-bg {
      position: relative;
      overflow: hidden;
    }
    .particle-bg::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: radial-gradient(circle at 20% 30%, rgba(255,59,15,0.15) 0%, transparent 60%);
      pointer-events: none;
    }

    .text-accent-glow {
      color: var(--accent);
      text-shadow: 0 0 12px rgba(0,229,255,0.5);
    }

    .hover-lift {
      transition: transform 0.3s ease, box-shadow 0.3s ease;
    }
    .hover-lift:hover {
      transform: translateY(-6px);
    }