/* roulang page: index */
:root {
      --primary: #E9402B;
      --primary-dark: #C5301F;
      --secondary: #1A1A2E;
      --light-bg: #F5F5F7;
      --accent: #00D4AA;
      --text-main: #1A1A2E;
      --text-sub: #6B7280;
      --border-light: #E5E7EB;
      --white: #FFFFFF;
      --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
      --shadow-hover: 0 8px 24px rgba(0, 0, 0, 0.12);
      --radius-sm: 4px;
      --radius-md: 6px;
      --radius-lg: 8px;
      --transition: 0.25s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: -apple-system, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background: var(--white);
      color: var(--text-main);
      line-height: 1.75;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }

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

    a {
      text-decoration: none;
      color: inherit;
    }

    button, .button {
      cursor: pointer;
      transition: var(--transition);
    }

    .grid-container {
      max-width: 1200px;
    }

    /* 导航栏 */
    .top-bar {
      background: var(--secondary);
      height: 64px;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      box-shadow: 0 2px 10px rgba(0,0,0,0.3);
    }

    .top-bar .menu {
      background: var(--secondary);
    }

    .top-bar .menu a {
      color: white;
      font-weight: 500;
      font-size: 0.95rem;
      padding: 0.5rem 1rem;
      transition: var(--transition);
      border-bottom: 2px solid transparent;
    }

    .top-bar .menu a:hover {
      border-bottom: 2px solid var(--primary);
      color: white;
    }

    .brand-logo {
      font-weight: 700;
      font-size: 1.5rem;
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      color: white !important;
    }

    .brand-logo i {
      color: var(--primary);
      margin-right: 6px;
      font-size: 1.4rem;
    }

    .nav-cta-button {
      background: var(--primary);
      color: white !important;
      padding: 10px 20px !important;
      border-radius: var(--radius-md);
      font-weight: 600;
      margin-left: 16px;
      white-space: nowrap;
      border-bottom: none !important;
    }

    .nav-cta-button:hover {
      background: var(--primary-dark);
      transform: scale(1.03);
      box-shadow: 0 0 12px rgba(233,64,43,0.5);
    }

    /* 移动端汉堡菜单内 CTA */
    .mobile-cta {
      background: var(--primary);
      color: white;
      text-align: center;
      margin: 8px 16px;
      padding: 12px;
      border-radius: var(--radius-md);
      font-weight: 600;
      display: block;
    }

    /* Hero */
    .hero-section {
      padding-top: 64px;
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: var(--light-bg);
    }

    .hero-content {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 2rem;
    }

    .hero-text {
      flex: 1 1 400px;
    }

    .hero-text h1 {
      font-size: 2.5rem;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 1rem;
    }

    .hero-text h1 span {
      color: var(--primary);
    }

    .hero-text .subtitle {
      font-size: 1.1rem;
      color: var(--text-sub);
      margin-bottom: 2rem;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-md);
      font-weight: 600;
      display: inline-block;
      text-align: center;
      border: none;
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      color: white;
    }

    .btn-ghost {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-md);
      font-weight: 600;
      display: inline-block;
    }

    .btn-ghost:hover {
      background: var(--primary);
      color: white;
    }

    .hero-image {
      flex: 1 1 400px;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-hover);
    }

    .hero-stats {
      display: flex;
      gap: 2rem;
      margin-top: 2.5rem;
      flex-wrap: wrap;
    }

    .stat-item .stat-number {
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.2;
    }

    .stat-item .stat-label {
      font-size: 0.85rem;
      color: var(--text-sub);
    }

    /* 通用板块标题 */
    .section-title {
      font-size: 1.8rem;
      font-weight: 700;
      margin-bottom: 2.5rem;
      position: relative;
      display: inline-block;
    }

    .section-title::after {
      content: '';
      display: block;
      width: 50px;
      height: 4px;
      background: var(--primary);
      margin-top: 8px;
      border-radius: 2px;
    }

    .text-center .section-title::after {
      margin-left: auto;
      margin-right: auto;
    }

    section {
      padding: 80px 0;
    }

    /* 卡片通用 */
    .card {
      background: white;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-sm);
      padding: 24px;
      transition: var(--transition);
      height: 100%;
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .icon-circle {
      width: 64px;
      height: 64px;
      background: var(--light-bg);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 1rem;
      color: var(--primary);
      font-size: 1.8rem;
    }

    /* 案例卡片特别样式 */
    .case-card {
      border-left: 5px solid var(--primary);
      padding-left: 16px;
    }

    .case-img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
      border-radius: var(--radius-md);
      margin-bottom: 1rem;
      border: 1px solid var(--border-light);
      background: #E5E7EB;
    }

    .tag {
      background: var(--accent);
      color: var(--secondary);
      font-weight: 600;
      font-size: 0.75rem;
      padding: 4px 10px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 0.5rem;
    }

    /* 训练步骤条 */
    .steps-container {
      display: flex;
      justify-content: space-between;
      position: relative;
      flex-wrap: wrap;
    }

    .step-item {
      flex: 1;
      text-align: center;
      position: relative;
      padding: 0 10px;
    }

    .step-number {
      font-size: 3.5rem;
      font-weight: 700;
      color: rgba(233,64,43,0.2);
      line-height: 1;
    }

    .step-connector {
      position: absolute;
      top: 30px;
      left: 70%;
      width: 60%;
      height: 2px;
      background: var(--border-light);
    }

    /* FAQ */
    .accordion-item {
      border-bottom: 1px solid var(--border-light);
    }

    .accordion-title {
      font-weight: 600;
      font-size: 1rem;
      background: white;
      padding: 16px;
      display: flex;
      align-items: center;
      cursor: pointer;
    }

    .accordion-title .q-mark {
      color: var(--primary);
      font-weight: 700;
      font-size: 1.3rem;
      margin-right: 12px;
      width: 24px;
    }

    .accordion-content {
      background: #F9FAFB;
      padding: 0 16px 16px 52px;
      color: var(--text-sub);
    }

    /* CTA 区块 */
    .cta-block {
      background: var(--primary);
      color: white;
      text-align: center;
    }

    .cta-block h2 {
      color: white;
    }

    .cta-block .btn-ghost-white {
      border: 2px solid white;
      color: white;
      background: transparent;
      padding: 14px 34px;
      font-weight: 700;
    }

    .cta-block .btn-ghost-white:hover {
      background: white;
      color: var(--primary);
    }

    /* 页脚 */
    .footer {
      background: var(--secondary);
      color: #9CA3AF;
      padding: 50px 0 20px;
    }

    .footer a:hover {
      color: white;
    }

    .footer-links {
      list-style: none;
      margin: 0;
      padding: 0;
    }

    .footer-links li {
      margin-bottom: 8px;
    }

    .social-icons i {
      font-size: 1.4rem;
      margin-right: 16px;
      color: #9CA3AF;
      transition: var(--transition);
    }

    .social-icons i:hover {
      color: var(--primary);
    }

    .copyright {
      border-top: 1px solid rgba(255,255,255,0.1);
      margin-top: 2rem;
      padding-top: 1.5rem;
      font-size: 0.85rem;
    }

    /* 响应式 */
    @media (max-width: 640px) {
      .hero-text h1 {
        font-size: 1.7rem;
      }
      .hero-buttons .btn-primary, .hero-buttons .btn-ghost {
        width: 100%;
      }
      section {
        padding: 50px 0;
      }
      .steps-container {
        flex-direction: column;
      }
      .step-connector {
        display: none;
      }
    }