/* roulang page: index */
:root {
      --primary: #E8380F;
      --primary-dark: #c42d0a;
      --secondary: #1A1A2E;
      --energy-gold: #F5A623;
      --bg-warm: #FBF9F6;
      --card-white: #FFFFFF;
      --card-alt: #F0EDE8;
      --text-main: #1A1A2E;
      --text-muted: #5C5B5A;
      --white: #FFFFFF;
      --shadow-sm: 0 8px 30px rgba(26, 26, 46, 0.06);
      --shadow-md: 0 16px 40px rgba(26, 26, 46, 0.12);
      --shadow-glow: 0 0 25px rgba(232, 56, 15, 0.5);
      --radius-lg: 28px;
      --radius-md: 20px;
      --radius-sm: 14px;
      --radius-btn: 50px;
      --font-head: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-body: "PingFang SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
      --font-number: "DIN Alternate", "PingFang SC", sans-serif;
      --transition: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    }

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

    html {
      scroll-behavior: smooth;
      background-color: var(--bg-warm);
    }

    body {
      font-family: var(--font-body);
      color: var(--text-main);
      background-color: var(--bg-warm);
      line-height: 1.75;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }

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

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

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

    button, .btn {
      font-family: var(--font-head);
      cursor: pointer;
      border: none;
      outline: none;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-head);
      letter-spacing: -0.02em;
    }

    h2 {
      font-size: clamp(28px, 4vw, 40px);
      font-weight: 700;
      margin-bottom: 16px;
    }

    /* 导航 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      height: 72px;
      display: flex;
      align-items: center;
      background: transparent;
      transition: background 0.3s ease, box-shadow 0.3s ease;
    }
    .main-header.scrolled {
      background: rgba(26, 26, 46, 0.97);
      box-shadow: 0 1px 0 var(--primary);
      backdrop-filter: blur(12px);
    }
    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      display: flex;
      flex-direction: column;
      font-family: var(--font-head);
      font-weight: 800;
      font-size: 28px;
      line-height: 1.2;
      color: var(--white);
      text-shadow: 0 2px 10px rgba(0,0,0,0.5);
      transition: color 0.2s;
    }
    .logo small {
      font-size: 12px;
      font-weight: 400;
      opacity: 0.8;
      letter-spacing: 0.5px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-weight: 500;
      color: rgba(255,255,255,0.9);
      font-size: 16px;
      position: relative;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .nav-cta {
      background: var(--primary);
      color: white;
      padding: 10px 28px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      letter-spacing: 1px;
      transition: all 0.2s ease;
    }
    .nav-cta:hover {
      background: #ff4a1a;
      box-shadow: var(--shadow-glow);
      transform: scale(1.05);
    }
    .hamburger {
      display: none;
      font-size: 28px;
      color: var(--primary);
      background: none;
      border: none;
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 80%;
      max-width: 320px;
      height: 100vh;
      background: var(--secondary);
      padding: 24px;
      display: flex;
      flex-direction: column;
      gap: 16px;
      transition: right 0.3s ease;
      z-index: 200;
      box-shadow: -10px 0 30px rgba(0,0,0,0.5);
    }
    .mobile-menu.open {
      right: 0;
    }
    .mobile-menu a, .mobile-menu .mobile-close {
      color: white;
      font-size: 18px;
      padding: 12px 20px;
      background: rgba(255,255,255,0.08);
      border-radius: 20px;
      font-weight: 600;
      display: block;
    }
    .mobile-close {
      align-self: flex-end;
      background: transparent;
      font-size: 28px;
      margin-bottom: 20px;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      color: white;
      padding: 120px 0 80px;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(26,26,46,0.85) 0%, rgba(26,26,46,0.4) 70%);
    }
    .hero .container {
      position: relative;
      display: flex;
      align-items: center;
      gap: 48px;
      flex-wrap: wrap;
    }
    .hero-left {
      flex: 1 1 500px;
    }
    .hero-right {
      flex: 1 1 400px;
      display: flex;
      justify-content: center;
      position: relative;
    }
    .hero h1 {
      font-size: clamp(36px, 6vw, 64px);
      font-weight: 900;
      background: linear-gradient(to right, var(--primary), var(--energy-gold));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 20px;
      color: rgba(255,255,255,0.85);
      margin-bottom: 32px;
      max-width: 500px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 16px 38px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 18px;
      transition: all 0.2s ease;
      box-shadow: 0 8px 20px rgba(232,56,15,0.4);
    }
    .btn-primary:hover {
      transform: scale(1.05);
      box-shadow: 0 0 30px var(--primary);
    }
    .btn-secondary {
      background: transparent;
      border: 2px solid white;
      color: white;
      padding: 16px 38px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 18px;
    }
    .btn-secondary:hover {
      background: white;
      color: var(--secondary);
    }
    .badge-float {
      background: rgba(26,26,46,0.8);
      backdrop-filter: blur(10px);
      color: var(--energy-gold);
      padding: 8px 20px;
      border-radius: 20px;
      font-weight: 700;
      font-size: 16px;
      display: inline-block;
      margin-bottom: 16px;
    }
    .mockup-stack {
      width: 300px;
      height: auto;
      border-radius: 36px;
      box-shadow: 0 30px 40px rgba(0,0,0,0.5);
    }

    section {
      padding: 100px 0;
    }

    .solution-cards {
      display: flex;
      gap: 32px;
      margin-top: 48px;
      align-items: flex-start;
    }
    .card {
      background: var(--card-white);
      border-radius: var(--radius-lg);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      flex: 1;
    }
    .card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-md);
    }
    .card-icon {
      font-size: 32px;
      color: var(--primary);
      margin-bottom: 16px;
    }
    .tag {
      background: var(--primary);
      color: white;
      font-size: 12px;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .data-wall {
      display: flex;
      gap: 32px;
      flex-wrap: wrap;
      margin-top: 40px;
    }
    .stat-circle {
      background: var(--card-alt);
      border-radius: 24px;
      padding: 28px;
      text-align: center;
      min-width: 160px;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
    }
    .testimonial-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding: 20px 0;
    }
    .testimonial-card {
      min-width: 280px;
      background: white;
      border-left: 5px solid var(--primary);
      padding: 24px;
      border-radius: 20px;
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      padding: 18px 24px;
      cursor: pointer;
      font-weight: 600;
      transition: 0.2s;
    }
    .faq-item:hover {
      border-left: 5px solid var(--primary);
    }
    .cta-dark {
      background: var(--secondary);
      text-align: center;
      padding: 80px 20px;
      color: white;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 32px;
      color: #ddd;
    }
    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .solution-cards { flex-direction: column; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .hero .container { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }