/* roulang page: index */
:root {
      --primary: #E63946;
      --primary-dark: #C1121F;
      --secondary-dark: #1D1D1D;
      --accent-gold: #F4A261;
      --accent-victory: #E9C46A;
      --bg-warm: #FDFBF7;
      --card-bg: #FFFFFF;
      --text-body: #333333;
      --text-muted: #666666;
      --text-light: #AAAAAA;
      --border-light: #E5E5E5;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --radius-lg: 20px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --radius-btn: 50px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Inter", "Poppins", sans-serif;
      --transition: 0.25s ease;
    }

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

    html {
      scroll-behavior: smooth;
      scroll-padding-top: 80px;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-body);
      line-height: 1.65;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    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;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      box-shadow: 0 2px 12px rgba(0,0,0,0.02);
      transition: background 0.3s, box-shadow 0.3s;
      padding: 16px 0;
    }

    .nav.scrolled {
      background: rgba(255,255,255,0.98);
      box-shadow: 0 4px 20px rgba(0,0,0,0.06);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--secondary-dark);
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .logo span {
      color: var(--primary);
    }

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

    .nav-links a {
      font-weight: 500;
      color: var(--secondary-dark);
      position: relative;
      padding: 4px 0;
      font-size: 1rem;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s;
    }

    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 12px 32px;
      font-weight: 600;
      box-shadow: 0 6px 16px rgba(230,57,70,0.3);
      border: none;
      font-size: 1rem;
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 10px 24px rgba(193,18,31,0.4);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--secondary-dark);
      color: var(--secondary-dark);
      border-radius: var(--radius-btn);
      padding: 12px 32px;
      font-weight: 600;
    }

    .btn-outline:hover {
      background: var(--secondary-dark);
      color: white;
      transform: translateY(-2px);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }

    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--secondary-dark);
      border-radius: 4px;
      transition: 0.3s;
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(253,251,247,0.98);
      backdrop-filter: blur(20px);
      z-index: 55;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
    }

    .mobile-menu.active {
      display: flex;
    }

    .mobile-menu a {
      font-size: 1.6rem;
      font-weight: 600;
      color: var(--secondary-dark);
    }

    .mobile-menu .close-btn {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 2rem;
      background: none;
      border: none;
      color: var(--secondary-dark);
    }

    /* Hero */
    .hero {
      padding: 140px 0 80px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      display: flex;
      align-items: center;
      min-height: 85vh;
      color: white;
    }

    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(29,29,29,0.7) 0%, rgba(230,57,70,0.35) 100%);
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
      display: flex;
      flex-direction: column;
      gap: 24px;
    }

    .hero h1 {
      font-size: clamp(2.5rem, 6vw, 3.8rem);
      font-weight: 800;
      letter-spacing: -0.5px;
      line-height: 1.2;
      color: white;
      text-shadow: 0 4px 20px rgba(0,0,0,0.3);
    }

    .hero .subtitle {
      font-size: 1.25rem;
      opacity: 0.9;
      max-width: 500px;
    }

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

    /* 通用区块 */
    section {
      padding: 80px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }

    .section-title h2 {
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--secondary-dark);
      margin-bottom: 12px;
    }

    .section-title p {
      color: var(--text-muted);
      font-size: 1.1rem;
    }

    /* 解决方案 */
    .solution-grid {
      display: flex;
      flex-direction: column;
      gap: 48px;
    }

    .solution-item {
      display: flex;
      align-items: center;
      gap: 48px;
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .solution-item:hover {
      box-shadow: var(--shadow-hover);
    }

    .solution-text {
      flex: 1;
    }

    .solution-text h3 {
      font-size: 1.8rem;
      font-weight: 700;
      margin-bottom: 12px;
      color: var(--secondary-dark);
    }

    .solution-img {
      flex: 1;
      border-radius: var(--radius-md);
      overflow: hidden;
    }

    .solution-img img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }

    .icon-circle {
      width: 48px;
      height: 48px;
      background: rgba(230,57,70,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-size: 1.5rem;
      margin-bottom: 16px;
      transition: 0.25s;
    }

    .solution-item:hover .icon-circle {
      background: var(--primary);
      color: white;
    }

    /* 优势卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .advantage-card {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 32px 28px;
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
      align-items: center;
    }

    .advantage-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }

    .badge-gold {
      background: var(--accent-victory);
      color: var(--secondary-dark);
      font-weight: 800;
      font-size: 1.7rem;
      padding: 8px 18px;
      border-radius: 30px;
      margin-top: 16px;
      display: inline-block;
    }

    /* 证言 */
    .testimonials {
      background: var(--secondary-dark);
      color: white;
    }

    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
    }

    .testimonial-card {
      background: rgba(255,255,255,0.06);
      backdrop-filter: blur(10px);
      border-radius: var(--radius-lg);
      padding: 32px;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .stars {
      color: var(--accent-victory);
      font-size: 1.2rem;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: #F5F5F5;
      border-radius: 12px;
      overflow: hidden;
    }

    .faq-question {
      padding: 18px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      background: #F5F5F5;
      border: none;
      width: 100%;
      text-align: left;
      font-size: 1.1rem;
      color: var(--secondary-dark);
    }

    .faq-answer {
      padding: 0 24px 20px;
      color: #555;
      display: none;
      background: white;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    .faq-icon {
      font-size: 1.8rem;
      font-weight: 300;
      transition: 0.2s;
    }

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

    .footer {
      background: var(--secondary-dark);
      color: var(--text-light);
      padding: 48px 0 24px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }

    @media (max-width: 1024px) {
      .cards-grid, .testimonial-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .solution-item {
        flex-direction: column;
      }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .cards-grid, .testimonial-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero {
        text-align: center;
        min-height: 70vh;
      }
      .hero-content {
        align-items: center;
      }
      .solution-item {
        padding: 24px;
      }
    }