/* roulang page: index */
:root {
      --primary: #00E5A0;
      --primary-glow: rgba(0, 229, 160, 0.4);
      --secondary: #7B2FF7;
      --bg-deep: #0A0E1A;
      --bg-card: rgba(17, 24, 39, 0.6);
      --glass-border: rgba(255, 255, 255, 0.08);
      --text-main: #FFFFFF;
      --text-body: #B0C4DE;
      --text-muted: #6B7C93;
      --radius-card: 16px;
      --radius-btn: 12px;
      --radius-input: 10px;
      --radius-tag: 20px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", system-ui, sans-serif;
      --nav-width: 72px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-deep);
      color: var(--text-body);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      display: flex;
      min-height: 100vh;
    }

    /* 左侧固定导航栏 (桌面端) */
    .app-nav {
      position: fixed;
      left: 0;
      top: 0;
      width: var(--nav-width);
      height: 100vh;
      background: rgba(10, 14, 26, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-right: 1px solid rgba(255, 255, 255, 0.06);
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 24px 0;
      z-index: 50;
      transition: transform 0.3s ease;
    }

    .nav-logo {
      margin-bottom: 48px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      color: var(--primary);
      font-weight: 700;
      font-size: 10px;
      letter-spacing: 1px;
    }
    .nav-logo i {
      font-size: 28px;
      filter: drop-shadow(0 0 8px var(--primary-glow));
    }

    .nav-menu {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 32px;
      flex: 1;
    }

    .nav-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      color: var(--text-muted);
      text-decoration: none;
      font-size: 10px;
      font-weight: 500;
      transition: color 0.2s;
      position: relative;
      width: 100%;
      text-align: center;
    }

    .nav-item i {
      font-size: 20px;
      transition: color 0.2s, text-shadow 0.2s;
    }

    .nav-item.active {
      color: #FFFFFF;
    }
    .nav-item.active i {
      color: var(--primary);
      text-shadow: 0 0 12px var(--primary-glow);
    }
    .nav-item.active::before {
      content: '';
      position: absolute;
      left: 0;
      top: -8px;
      height: 40px;
      width: 3px;
      background: var(--primary);
      box-shadow: 0 0 14px var(--primary-glow);
      border-radius: 0 4px 4px 0;
    }

    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: rgba(10, 14, 26, 0.9);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255,255,255,0.06);
      z-index: 60;
      align-items: center;
      justify-content: space-between;
      padding: 0 20px;
    }
    .mobile-logo {
      display: flex;
      align-items: center;
      gap: 6px;
      color: var(--primary);
      font-weight: 700;
      font-size: 16px;
    }
    .mobile-logo i {
      font-size: 24px;
    }
    .hamburger {
      color: var(--text-main);
      font-size: 24px;
      background: none;
      border: none;
      cursor: pointer;
    }
    .mobile-drawer {
      position: fixed;
      top: 0;
      left: 0;
      width: 280px;
      height: 100vh;
      background: rgba(10, 14, 26, 0.95);
      backdrop-filter: blur(24px);
      -webkit-backdrop-filter: blur(24px);
      z-index: 70;
      transform: translateX(-100%);
      transition: transform 0.3s ease;
      display: flex;
      flex-direction: column;
      padding: 32px 24px;
      border-right: 1px solid rgba(255,255,255,0.08);
    }
    .mobile-drawer.open {
      transform: translateX(0);
    }
    .drawer-close {
      align-self: flex-end;
      background: none;
      border: none;
      color: white;
      font-size: 28px;
      margin-bottom: 40px;
      cursor: pointer;
    }
    .drawer-nav {
      display: flex;
      flex-direction: column;
      gap: 28px;
    }
    .drawer-nav a {
      color: var(--text-body);
      font-size: 18px;
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 8px 0;
      border-bottom: 1px solid rgba(255,255,255,0.05);
    }
    .drawer-nav a i {
      width: 24px;
      color: var(--primary);
    }

    /* 主内容区域 */
    .main-content {
      margin-left: var(--nav-width);
      width: 100%;
      overflow-x: hidden;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 32px;
    }

    section {
      padding: 80px 0;
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--bg-card);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      transition: all 0.25s ease;
    }
    .glass-card:hover {
      border-color: rgba(0,229,160,0.3);
      box-shadow: 0 8px 32px rgba(0,229,160,0.15);
      transform: translateY(-4px);
    }

    .btn-primary {
      background: var(--primary);
      color: #0A0E1A;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      box-shadow: 0 0 20px var(--primary-glow);
      transition: all 0.2s;
      font-size: 16px;
      letter-spacing: 0.5px;
    }
    .btn-primary:hover {
      box-shadow: 0 0 28px rgba(0,229,160,0.6);
      background: #00f0b3;
    }

    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      cursor: pointer;
      transition: all 0.2s;
      font-size: 16px;
    }
    .btn-outline:hover {
      background: rgba(0,229,160,0.1);
      border-color: #00f0b3;
      color: #fff;
    }

    .accent-text {
      color: var(--primary);
    }
    .muted-text {
      color: var(--text-muted);
    }

    @media (max-width: 768px) {
      .app-nav {
        display: none;
      }
      .mobile-header {
        display: flex;
      }
      .main-content {
        margin-left: 0;
        padding-top: 64px;
      }
      .container {
        padding: 0 20px;
      }
      section {
        padding: 60px 0;
      }
      h1 {
        font-size: 36px !important;
      }
      h2 {
        font-size: 28px !important;
      }
    }