/* roulang page: index */
:root {
      --primary-purple: #7C3AED;
      --primary-orange: #F97316;
      --deep-bg: #0F0F1A;
      --warm-gold: #FBBF24;
      --text-main: #1E1B2E;
      --text-secondary: #6B6B7B;
      --light-bg: #F8F7FC;
      --card-white: #FFFFFF;
      --radius-xl: 20px;
      --radius-lg: 16px;
      --radius-md: 12px;
      --shadow-card: 0 8px 30px rgba(124, 58, 237, 0.12);
      --shadow-hover: 0 16px 40px rgba(124, 58, 237, 0.22);
      --transition-smooth: 0.3s ease;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', sans-serif;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      color: var(--text-main);
      background-color: #fff;
      line-height: 1.8;
      margin: 0;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      margin: 0;
    }

    h1 {
      font-size: 3.5rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      line-height: 1.2;
    }

    h2 {
      font-size: 2.25rem;
      font-weight: 700;
      line-height: 1.3;
    }

    h3 {
      font-size: 1.5rem;
      font-weight: 600;
      line-height: 1.4;
    }

    h4 {
      font-size: 1.1rem;
      font-weight: 600;
    }

    p {
      font-size: 1rem;
      font-weight: 400;
      color: var(--text-secondary);
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-body);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      transition: all var(--transition-smooth);
      border: none;
      outline: none;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      transition: background 0.3s, box-shadow 0.3s, backdrop-filter 0.3s;
      background: transparent;
      backdrop-filter: blur(0px);
    }

    .navbar.scrolled {
      background: rgba(255, 255, 255, 0.98);
      box-shadow: 0 1px 8px rgba(0,0,0,0.05);
      backdrop-filter: blur(12px);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo-text {
      font-family: var(--font-heading);
      font-size: 1.8rem;
      font-weight: 800;
      background: linear-gradient(135deg, var(--primary-purple), var(--primary-orange));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 0.5px;
    }

    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
    }

    .nav-links a {
      font-weight: 500;
      color: rgba(255,255,255,0.9);
      transition: color 0.2s;
    }

    .navbar.scrolled .nav-links a {
      color: var(--text-main);
    }

    .nav-links a:hover {
      color: var(--primary-purple);
    }

    .mobile-menu-btn {
      display: none;
      background: transparent;
      border: none;
      font-size: 1.8rem;
      color: white;
    }

    .navbar.scrolled .mobile-menu-btn {
      color: var(--text-main);
    }

    /* 移动端导航 */
    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .mobile-menu-btn {
        display: block;
      }
      .mobile-nav-open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(15,15,26,0.98);
        backdrop-filter: blur(20px);
        padding: 1.5rem;
        gap: 1.5rem;
      }
      .navbar.scrolled .mobile-nav-open {
        background: white;
      }
      .mobile-nav-open a {
        color: white;
        font-size: 1.2rem;
      }
      .navbar.scrolled .mobile-nav-open a {
        color: var(--text-main);
      }
    }

    /* 按钮系统 */
    .btn-primary {
      background: linear-gradient(135deg, #7C3AED, #F97316);
      color: white;
      border-radius: var(--radius-md);
      padding: 0.9rem 2rem;
      font-size: 1.1rem;
      letter-spacing: 0.03em;
      box-shadow: 0 8px 18px rgba(124,58,237,0.3);
    }

    .btn-primary:hover {
      filter: brightness(1.1);
      transform: scale(1.05);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary-purple);
      color: var(--primary-purple);
      border-radius: var(--radius-md);
      padding: 0.9rem 2rem;
      font-size: 1.1rem;
    }

    .btn-outline:hover {
      background: rgba(124,58,237,0.08);
    }

    .btn-gold {
      background: var(--warm-gold);
      color: #1E1B2E;
      border-radius: 16px;
      padding: 1rem 2.5rem;
      font-weight: 700;
      font-size: 1.2rem;
    }

    /* 卡片悬浮 */
    .hover-card {
      transition: transform 0.3s ease, box-shadow 0.3s ease;
    }
    .hover-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }

    .gradient-text {
      background: linear-gradient(135deg, #7C3AED, #F97316);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .badge-gold {
      background: var(--warm-gold);
      color: #1E1B2E;
      font-weight: 700;
      border-radius: 8px;
      padding: 0.2rem 1rem;
      display: inline-block;
    }

    @media (max-width: 640px) {
      h1 { font-size: 2.2rem; }
      h2 { font-size: 1.7rem; }
      .container { padding: 0 1rem; }
    }