/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --primary: #FF2D55;
      --primary-glow: rgba(255, 45, 85, 0.4);
      --secondary: #00F0FF;
      --secondary-glow: rgba(0, 240, 255, 0.3);
      --accent-gold: #FFB800;
      --bg-deep: #0A0E27;
      --bg-card: #1A1F3A;
      --bg-light: #F5F5F7;
      --text-primary: #FFFFFF;
      --text-secondary: #B0B8D0;
      --text-dark: #1E1E2F;
      --border-dim: rgba(255, 255, 255, 0.08);
      --border-neon: rgba(0, 240, 255, 0.25);
      --radius-card: 1rem;
      --radius-btn: 0.5rem;
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --shadow-hover: 0 12px 36px rgba(255, 45, 85, 0.2);
      --font-title: "DIN Alternate", "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-body: "Inter", "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-mono: "JetBrains Mono", "SF Mono", monospace;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg-deep);
      color: var(--text-primary);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

    a {
      color: inherit;
      text-decoration: none;
      transition: color 0.2s ease;
    }

    button, input {
      font-family: inherit;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    /* 导航栏 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      background: rgba(10, 14, 39, 0.85);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-bottom: 1px solid rgba(255, 45, 85, 0.15);
      transition: background 0.3s;
    }

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

    .nav-links {
      display: flex;
      gap: 2rem;
      list-style: none;
    }

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
      padding: 0.25rem 0;
      letter-spacing: 0.3px;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 50%;
      transform: translateX(-50%) scaleX(0);
      width: 100%;
      height: 2px;
      background: var(--secondary);
      transition: transform 0.25s ease;
    }

    .nav-links a:hover {
      color: var(--secondary);
    }
    .nav-links a:hover::after {
      transform: translateX(-50%) scaleX(1);
    }

    .logo-area {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      font-family: var(--font-title);
      font-size: 1.4rem;
      font-weight: 700;
      letter-spacing: 2px;
      color: white;
    }
    .logo-icon {
      width: 12px;
      height: 12px;
      background: var(--primary);
      transform: rotate(45deg);
      box-shadow: 0 0 12px var(--primary-glow);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      padding: 8px;
      z-index: 60;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: white;
      border-radius: 2px;
      transition: all 0.3s;
    }

    .mobile-menu {
      display: none;
      position: fixed;
      inset: 0;
      background: var(--bg-deep);
      flex-direction: column;
      justify-content: center;
      align-items: flex-start;
      padding: 2rem;
      z-index: 55;
      backdrop-filter: blur(20px);
    }
    .mobile-menu a {
      font-size: 1.8rem;
      font-weight: 600;
      margin: 1.2rem 0;
      color: white;
      border-bottom: 1px solid var(--border-dim);
      width: 100%;
      padding-bottom: 0.5rem;
    }

    /* 版块通用 */
    .section {
      padding: 5rem 0;
    }
    .section-light {
      background-color: var(--bg-light);
      color: var(--text-dark);
    }
    .section-dark {
      background: linear-gradient(135deg, #0A0E27 0%, #1A1030 50%, #0D1B2A 100%);
    }
    .section-title {
      font-family: var(--font-title);
      font-size: 2.5rem;
      font-weight: 700;
      text-align: center;
      margin-bottom: 1rem;
      letter-spacing: 1px;
    }
    .section-subtitle {
      text-align: center;
      color: var(--text-secondary);
      max-width: 600px;
      margin: 0 auto 3rem;
    }

    /* 按钮 */
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 0.75rem 1.8rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      box-shadow: 0 4px 14px rgba(255, 45, 85, 0.3);
    }
    .btn-primary:hover {
      background: #FF4D6D;
      box-shadow: 0 0 24px var(--primary-glow);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--secondary);
      color: var(--secondary);
      padding: 0.75rem 1.8rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: all 0.3s;
    }
    .btn-outline:hover {
      background: rgba(0, 240, 255, 0.08);
      box-shadow: 0 0 18px var(--secondary-glow);
    }

    /* 卡片 */
    .card {
      background: rgba(26, 31, 58, 0.7);
      backdrop-filter: blur(12px);
      border: 1px solid var(--border-dim);
      border-radius: var(--radius-card);
      padding: 2rem;
      transition: all 0.3s ease;
    }
    .card:hover {
      transform: translateY(-6px);
      border-color: rgba(255, 45, 85, 0.4);
      box-shadow: var(--shadow-hover);
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .mobile-menu.active { display: flex; }
      .section-title { font-size: 2rem; }
    }
    @media (max-width: 640px) {
      .section { padding: 3.5rem 0; }
      .section-title { font-size: 1.8rem; }
    }