/* roulang page: index */
:root {
      --primary: #1E6F9F;
      --primary-light: #0EA5E9;
      --primary-dark: #155E85;
      --soft: #F8FAFC;
      --soft-blue: #EBF4FA;
      --deep: #1A202C;
      --muted: #4A5568;
      --faint: #A0AEC0;
      --success: #10B981;
      --danger: #EF4444;
      --border: #E2E8F0;
      --radius-card: 20px;
      --radius-btn: 10px;
      --radius-input: 10px;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      margin: 0;
      background-color: #FFFFFF;
      color: #1A202C;
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(8px);
      -webkit-backdrop-filter: blur(8px);
      border-bottom: 1px solid var(--border);
      z-index: 50;
      transition: box-shadow 0.3s;
      display: flex;
      align-items: center;
    }
    #header.scrolled {
      box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    }
    .nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo img {
      height: 36px;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-menu a {
      font-size: 15px;
      font-weight: 500;
      color: var(--deep);
      position: relative;
      padding: 8px 0;
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: all 0.3s;
      transform: translateX(-50%);
    }
    .nav-menu a:hover {
      color: var(--primary);
    }
    .nav-menu a:hover::after {
      width: 60%;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      cursor: pointer;
      transition: all 0.25s;
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(30,111,159,0.25);
    }
    .btn-outline {
      background: transparent;
      color: var(--primary);
      border: 1.5px solid var(--primary);
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      cursor: pointer;
      transition: all 0.25s;
    }
    .btn-outline:hover {
      background: var(--soft-blue);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(30,111,159,0.1);
    }
    /* 汉堡菜单 */
    #menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 28px;
      color: var(--deep);
      cursor: pointer;
    }
    .mobile-drawer {
      display: none;
      position: fixed;
      top: 0;
      right: 0;
      width: 80%;
      max-width: 320px;
      height: 100vh;
      background: white;
      z-index: 100;
      box-shadow: -4px 0 20px rgba(0,0,0,0.1);
      flex-direction: column;
      padding: 24px;
      transform: translateX(100%);
      transition: transform 0.3s ease;
    }
    .mobile-drawer.open {
      transform: translateX(0);
    }
    .drawer-overlay {
      display: none;
      position: fixed;
      inset: 0;
      background: rgba(0,0,0,0.3);
      z-index: 90;
    }
    .drawer-overlay.active {
      display: block;
    }
    @media (max-width: 1023px) {
      .nav-menu {
        display: none;
      }
      #menu-toggle {
        display: block;
      }
      .mobile-drawer {
        display: flex;
      }
    }
    /* 区块间距 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 767px) {
      section {
        padding: 64px 0;
      }
      h1 {
        font-size: 32px !important;
      }
      h2 {
        font-size: 24px !important;
      }
    }
    .float-animation {
      animation: float 3s ease-in-out infinite;
    }
    @keyframes float {
      0% { transform: translateY(0); }
      50% { transform: translateY(-10px); }
      100% { transform: translateY(0); }
    }
    .pulse-arrow {
      animation: pulse 2s infinite;
    }
    @keyframes pulse {
      0% { opacity: 1; transform: translateY(0); }
      50% { opacity: 0.6; transform: translateY(8px); }
      100% { opacity: 1; transform: translateY(0); }
    }