/* roulang page: index */
:root {
      --primary-deep: #0A0F1E;
      --accent-orange: #FF4D2E;
      --bg-cool-gray: #F5F6FA;
      --card-dark: #1E2A3A;
      --fl-green: #00C9A7;
      --amber: #FFB800;
      --text-white: #FFFFFF;
      --text-sub-white: #E0E4EB;
      --text-main: #1A1F2B;
      --text-muted: #5B667A;
      --radius-lg: 16px;
      --radius-pill: 50px;
      --shadow-card: 0 4px 20px rgba(10,15,30,0.06);
      --shadow-hover: 0 12px 32px rgba(10,15,30,0.12);
      --transition-smooth: 0.25s ease;
    }
    body {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      background-color: var(--bg-cool-gray);
      color: var(--text-main);
      line-height: 1.7;
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }
    .container-custom {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 2rem;
      padding-right: 2rem;
    }
    @media (max-width: 768px) {
      .container-custom {
        padding-left: 1.25rem;
        padding-right: 1.25rem;
      }
    }
    /* 导航栏 */
    .nav-blur {
      background: rgba(10, 15, 30, 0.88);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      height: 72px;
      transition: box-shadow 0.3s;
    }
    .nav-shadow {
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    }
    .search-box {
      width: 320px;
      background: rgba(255,255,255,0.08);
      border: 1px solid rgba(255,255,255,0.18);
      border-radius: 50px;
      transition: all 0.2s;
    }
    .search-box:focus-within {
      background: rgba(255,255,255,0.14);
      border-color: var(--fl-green);
      box-shadow: 0 0 0 3px rgba(0,201,167,0.2);
    }
    .search-input {
      background: transparent;
      border: none;
      color: white;
      outline: none;
      width: 100%;
      padding-left: 2.5rem;
    }
    .search-input::placeholder {
      color: rgba(224,228,235,0.7);
      font-weight: 400;
    }
    @media (max-width: 768px) {
      .search-box {
        width: 100%;
        max-width: 280px;
      }
    }
    .nav-link {
      color: var(--text-sub-white);
      transition: color 0.2s;
      position: relative;
    }
    .nav-link:hover {
      color: white;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--accent-orange);
      transition: width 0.25s ease;
    }
    .nav-link:hover::after {
      width: 100%;
    }
    /* 按钮 */
    .btn-primary {
      background: var(--accent-orange);
      color: white;
      border-radius: 50px;
      padding: 0.75rem 2rem;
      font-weight: 600;
      transition: background 0.2s, box-shadow 0.2s;
      box-shadow: 0 4px 12px rgba(255,77,46,0.3);
      border: none;
      cursor: pointer;
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: #D93A1E;
      box-shadow: 0 8px 20px rgba(255,77,46,0.5);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid white;
      color: white;
      border-radius: 50px;
      padding: 0.75rem 2rem;
      font-weight: 600;
      transition: all 0.2s;
      cursor: pointer;
      display: inline-block;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.15);
      border-color: white;
    }
    .btn-outline-dark {
      border-color: var(--text-main);
      color: var(--text-main);
    }
    .btn-outline-dark:hover {
      background: rgba(10,15,30,0.05);
    }
    /* 卡片与装饰 */
    .card-hover {
      transition: transform 0.25s ease, box-shadow 0.25s ease;
      border-radius: var(--radius-lg);
      background: white;
      box-shadow: var(--shadow-card);
    }
    .card-hover:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .highlight-number {
      color: var(--fl-green);
      font-weight: 800;
      font-size: 3rem;
      line-height: 1.2;
    }
    .badge-hot {
      background: var(--amber);
      color: #0A0F1E;
      font-weight: 700;
      padding: 0.2rem 0.8rem;
      border-radius: 50px;
      font-size: 0.75rem;
      letter-spacing: 0.3px;
    }
    /* 方案表 */
    .plan-recommend {
      background: linear-gradient(180deg, rgba(0,201,167,0.08) 0%, rgba(0,201,167,0.02) 100%);
      border-radius: 16px 16px 0 0;
    }
    /* FAQ */
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, background 0.2s;
      background: transparent;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      background: #F5F6FA;
      padding: 1rem;
      margin-top: 0.5rem;
      border-radius: 12px;
    }
    .faq-item.active .faq-icon {
      transform: rotate(180deg);
    }
    .faq-icon {
      transition: transform 0.3s;
    }
    /* 瀑布流模拟 */
    .waterfall-item:nth-child(odd) {
      margin-top: 0;
    }
    .waterfall-item:nth-child(even) {
      margin-top: 2rem;
    }
    @media (max-width: 768px) {
      .waterfall-item:nth-child(even) {
        margin-top: 0;
      }
    }
    /* 装饰线条 */
    .hero-glow {
      background: radial-gradient(circle at 30% 40%, rgba(255,77,46,0.25) 0%, transparent 60%);
    }