/* roulang page: index */
:root {
      --primary: #E6390C;
      --primary-dark: #c42f08;
      --secondary: #1A1A2E;
      --accent: #F4A261;
      --bg-light: #F8F9FA;
      --white: #FFFFFF;
      --gray-400: #6C757D;
      --gray-300: #DEE2E6;
      --gray-200: #e9ecef;
      --shadow-sm: 0 4px 16px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 24px rgba(230,57,12,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition: 0.25s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-number: "Inter", "SF Pro Display", system-ui;
      --max-width: 1280px;
      --header-height: 72px;
      --header-height-mobile: 60px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: #212529;
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: var(--transition);
      font-weight: 600;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: var(--header-height);
      background: transparent;
      transition: background 0.3s, box-shadow 0.3s;
      display: flex;
      align-items: center;
    }

    .header.scrolled {
      background: var(--white);
      box-shadow: 0 2px 12px rgba(0,0,0,0.08);
      height: var(--header-height);
    }

    .header .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 800;
      font-size: 1.6rem;
      color: var(--white);
      letter-spacing: -0.5px;
      transition: color 0.3s;
    }
    .header.scrolled .logo {
      color: var(--secondary);
    }
    .logo i {
      font-size: 2rem;
      color: var(--primary);
    }

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

    .nav-link {
      font-weight: 500;
      font-size: 0.95rem;
      color: rgba(255,255,255,0.85);
      padding: 8px 0;
      position: relative;
    }
    .header.scrolled .nav-link {
      color: var(--secondary);
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.3s;
    }
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      box-shadow: 0 4px 10px rgba(230,57,12,0.3);
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(230,57,12,0.4);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-btn);
      padding: 12px 28px;
    }
    .btn-outline:hover {
      background: rgba(230,57,12,0.08);
      transform: translateY(-2px);
    }

    .btn-white {
      background: white;
      color: var(--primary);
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      font-weight: 700;
    }

    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: white;
      background: none;
      border: none;
    }
    .header.scrolled .hamburger {
      color: var(--secondary);
    }

    /* Hero */
    .hero {
      background: linear-gradient(135deg, #1A1A2E 0%, #2a2a4a 100%);
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding-top: var(--header-height);
      color: white;
      position: relative;
      overflow: hidden;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 40px;
    }
    .hero-text {
      flex: 1;
    }
    .hero-image {
      flex: 1;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 420px;
      border-radius: 24px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      position: relative;
      overflow: hidden;
    }
    .hero-image::after {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(230,57,12,0.25);
      mix-blend-mode: overlay;
    }

    h1 {
      font-size: 48px;
      line-height: 1.2;
      font-weight: 800;
      letter-spacing: -0.5px;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 18px;
      opacity: 0.9;
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    /* 区块通用 */
    section {
      padding: 90px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }
    h2 {
      font-size: 36px;
      font-weight: 700;
      color: var(--secondary);
    }
    .section-sub {
      color: var(--gray-400);
      font-size: 1.1rem;
      margin-top: 12px;
    }

    /* 功能卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .feature-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: left;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 64px;
      height: 64px;
      background: rgba(230,57,12,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 2rem;
    }
    .feature-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 12px;
    }

    /* 场景 */
    .scenarios-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .scene-card {
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .scene-img {
      height: 240px;
      background-size: cover;
      background-position: center;
    }
    .scene-info {
      padding: 24px;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      box-shadow: var(--shadow-sm);
    }
    .metric {
      font-family: var(--font-number);
      font-size: 42px;
      font-weight: 700;
      color: var(--primary);
    }

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .price-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      border: 2px solid transparent;
      position: relative;
    }
    .price-card.featured {
      border-color: var(--accent);
      background: #fff9f2;
      box-shadow: 0 12px 28px rgba(0,0,0,0.1);
    }
    .badge {
      background: var(--accent);
      color: #1A1A2E;
      padding: 4px 16px;
      border-radius: 20px;
      font-weight: 600;
      font-size: 0.8rem;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--gray-300);
    }
    .faq-question {
      width: 100%;
      padding: 20px 0;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      background: transparent;
      font-size: 1.1rem;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--gray-400);
      padding: 0 0;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }

    /* CTA 横幅 */
    .cta-band {
      background: var(--primary);
      color: white;
      text-align: center;
      padding: 80px 0;
    }

    /* Footer */
    .footer {
      background: var(--secondary);
      color: #ccc;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    .footer a:hover {
      color: var(--primary);
    }

    @media (max-width: 1024px) {
      .features-grid, .scenarios-grid, .cases-grid, .pricing-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 768px) {
      .hamburger {
        display: block;
      }
      .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        height: 100vh;
        background: white;
        flex-direction: column;
        padding: 100px 30px;
        transition: 0.3s;
        box-shadow: -5px 0 25px rgba(0,0,0,0.1);
        gap: 28px;
      }
      .nav-menu.active {
        right: 0;
      }
      .nav-link { color: var(--secondary) !important; }
      .hero .container {
        flex-direction: column;
      }
      h1 { font-size: 36px; }
      .features-grid, .scenarios-grid, .cases-grid, .pricing-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }