/* roulang page: index */
:root {
      --primary: #D42E1A;
      --primary-hover: #B82515;
      --secondary-dark: #1A1A2E;
      --accent-gold: #F5A623;
      --bg-warm: #FDFBF7;
      --card-bg: #FFFFFF;
      --border-soft: #E5E0D9;
      --text-main: #2C2C2C;
      --text-muted: #5A5A5A;
      --success-green: #0F9B6B;
      --shadow-sm: 0 4px 20px rgba(26, 26, 46, 0.06);
      --shadow-hover: 0 8px 30px rgba(26, 26, 46, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      background-color: var(--bg-warm);
      color: var(--text-main);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 700;
      letter-spacing: -0.02em;
    }

    .container {
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      transition: background 0.3s ease, box-shadow 0.3s ease;
      background: transparent;
    }
    .navbar.scrolled {
      background: rgba(255, 255, 255, 0.96);
      backdrop-filter: blur(16px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.05);
    }
    .nav-link {
      color: white;
      font-weight: 500;
      font-size: 15px;
      transition: color 0.2s;
      text-decoration: none;
      position: relative;
    }
    .navbar.scrolled .nav-link {
      color: var(--secondary-dark);
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s;
    }
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
      display: inline-block;
      text-decoration: none;
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: scale(1.02);
    }
    .btn-outline-light {
      border: 2px solid white;
      color: white;
      background: transparent;
      padding: 10px 26px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: all 0.25s;
      text-decoration: none;
    }
    .btn-outline-light:hover {
      background: rgba(255,255,255,0.15);
    }
    .btn-outline-primary {
      border: 2px solid var(--primary);
      color: var(--primary);
      background: transparent;
      padding: 10px 26px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: all 0.25s;
    }
    .btn-outline-primary:hover {
      background: rgba(212,46,26,0.1);
    }

    /* 移动菜单 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: var(--secondary-dark);
      transform: translateX(100%);
      transition: transform 0.35s ease;
      z-index: 60;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
    }
    .mobile-menu.open {
      transform: translateX(0);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      justify-content: space-around;
      width: 24px;
      height: 20px;
      background: transparent;
      border: none;
      cursor: pointer;
      padding: 0;
      z-index: 70;
      position: relative;
    }
    .hamburger span {
      width: 100%;
      height: 2px;
      background: white;
      transition: all 0.3s;
      display: block;
    }
    .navbar.scrolled .hamburger span {
      background: var(--secondary-dark);
    }
    .hamburger.open span:nth-child(1) {
      transform: rotate(45deg) translate(5px, 5px);
    }
    .hamburger.open span:nth-child(2) {
      opacity: 0;
    }
    .hamburger.open span:nth-child(3) {
      transform: rotate(-45deg) translate(5px, -5px);
    }

    @media (max-width: 1023px) {
      .desktop-nav {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .mobile-menu a {
        color: white;
        font-size: 22px;
        margin: 16px 0;
        text-decoration: none;
      }
    }

    .section-spacing {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      .section-spacing {
        padding: 60px 0;
      }
    }

.animate-fadeInUp {
      animation: fadeInUp 0.8s ease-out;
    }
    @keyframes fadeInUp {
      from { opacity: 0; transform: translateY(20px); }
      to { opacity: 1; transform: translateY(0); }
    }
    html { scroll-behavior: smooth; }