/* roulang page: index */
:root {
      --primary: #FF5E13;
      --primary-dark: #E04D0A;
      --secondary: #0D0F14;
      --accent: #A855F7;
      --surface: #1A1D24;
      --text-primary: #FFFFFF;
      --text-secondary: #9CA3AF;
      --text-disabled: #4B5563;
      --gradient-brand: linear-gradient(135deg, #FF5E13 0%, #A855F7 100%);
      --radius-xl: 24px;
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-full: 999px;
      --shadow-card: 0 4px 24px rgba(255, 94, 19, 0.08);
      --shadow-hover: 0 8px 32px rgba(168, 85, 247, 0.15);
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: 'Inter', 'Noto Sans SC', system-ui, sans-serif;
      background-color: var(--secondary);
      color: var(--text-primary);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease, opacity 0.2s ease;
    }
    button {
      font-family: inherit;
      cursor: pointer;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航栏 */
    .navbar {
      background-color: var(--secondary);
      border-bottom: 1px solid rgba(255, 94, 19, 0.2);
      position: sticky;
      top: 0;
      z-index: 50;
      backdrop-filter: blur(8px);
    }
    .nav-link {
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 1rem;
      position: relative;
      padding: 8px 0;
      transition: color 0.2s;
    }
    .nav-link:hover {
      color: white;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 50%;
      transform: translateX(-50%);
      width: 0;
      height: 4px;
      border-radius: 2px;
      background-color: var(--accent);
      transition: width 0.2s ease;
    }
    .nav-link:hover::after {
      width: 8px;
    }
    .btn-primary {
      background: var(--gradient-brand);
      color: white;
      font-weight: 600;
      border-radius: var(--radius-full);
      padding: 10px 24px;
      box-shadow: 0 0 12px rgba(255, 94, 19, 0.4);
      transition: all 0.25s ease;
      display: inline-block;
      text-align: center;
      border: none;
    }
    .btn-primary:hover {
      transform: scale(1.05);
      box-shadow: 0 0 20px rgba(168, 85, 247, 0.6);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      border-radius: var(--radius-md);
      padding: 12px 28px;
      transition: all 0.25s ease;
      display: inline-block;
    }
    .btn-outline:hover {
      background: rgba(255, 94, 19, 0.1);
      border-color: var(--accent);
      color: var(--accent);
    }
    .btn-text {
      color: var(--accent);
      font-weight: 500;
      text-decoration: underline;
      text-underline-offset: 4px;
      transition: all 0.2s;
      cursor: pointer;
      background: none;
      border: none;
    }
    .btn-text:hover {
      text-decoration-thickness: 2px;
      color: var(--primary);
    }
    /* 区块标题 */
    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      line-height: 1.3;
      text-align: center;
      margin-bottom: 0.5rem;
      letter-spacing: -0.3px;
      position: relative;
      display: inline-block;
      left: 50%;
      transform: translateX(-50%);
    }
    .section-title::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 50%;
      transform: translateX(-50%);
      width: 60px;
      height: 4px;
      border-radius: 2px;
      background: var(--gradient-brand);
    }
    .section-subtitle {
      color: var(--text-secondary);
      text-align: center;
      font-size: 1.125rem;
      margin: 20px auto 48px;
      max-width: 600px;
    }
    /* 卡片基础 */
    .card {
      background: var(--surface);
      border-radius: var(--radius-xl);
      box-shadow: var(--shadow-card);
      transition: box-shadow 0.3s ease, transform 0.2s;
    }
    .card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .badge {
      background: rgba(168, 85, 247, 0.15);
      color: var(--accent);
      border: 1px solid var(--accent);
      border-radius: var(--radius-full);
      padding: 4px 12px;
      font-size: 0.8rem;
      font-weight: 600;
    }
    /* Hero 浮动动画 */
    @keyframes float {
      0% { transform: translateY(0px); }
      50% { transform: translateY(-8px); }
      100% { transform: translateY(0px); }
    }
    .float-card-1 { animation: float 3s ease-in-out infinite; }
    .float-card-2 { animation: float 3s ease-in-out 0.2s infinite; }
    .float-card-3 { animation: float 3s ease-in-out 0.4s infinite; }
    /* 脉冲点 */
    @keyframes pulse-dot {
      0% { transform: scale(0.8); opacity: 0.7; }
      50% { transform: scale(1.4); opacity: 1; }
      100% { transform: scale(0.8); opacity: 0.7; }
    }
    .pulse-dot {
      width: 8px;
      height: 8px;
      background-color: var(--accent);
      border-radius: 50%;
      display: inline-block;
      animation: pulse-dot 1.8s infinite;
    }
    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .faq-question {
      cursor: pointer;
      padding: 20px 0;
      display: flex;
      align-items: center;
      justify-content: space-between;
      font-weight: 500;
      font-size: 1.25rem;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: var(--surface);
      border-left: 4px solid var(--accent);
      padding-left: 20px;
      margin-left: 12px;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px 20px;
    }
    .faq-icon {
      color: var(--primary);
      font-size: 1.2rem;
      transition: color 0.2s;
    }
    .faq-item.active .faq-icon {
      color: var(--accent);
    }
    /* 移动端汉堡菜单 */
    .mobile-menu {
      display: none;
      flex-direction: column;
      background: var(--secondary);
      position: absolute;
      top: 70px;
      left: 0;
      width: 100%;
      padding: 20px;
      border-bottom: 1px solid var(--primary);
    }
    #menu-toggle:checked ~ .mobile-menu {
      display: flex;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
      h1 {
        font-size: 2.5rem !important;
        line-height: 1.2 !important;
      }
      .section-title {
        font-size: 2rem;
      }
      .mobile-menu {
        display: none;
      }
    }