/* roulang page: index */
:root {
      --primary: #4E6EF2;
      --primary-light: rgba(78, 110, 242, 0.08);
      --primary-glow: rgba(78, 110, 242, 0.2);
      --success: #00B578;
      --warning: #FF9F0A;
      --error: #FA5151;
      --bg-base: #F5F6FA;
      --bg-white: #FFFFFF;
      --bg-dark: #1F2329;
      --text-primary: #1F2329;
      --text-secondary: #86909C;
      --text-disabled: #C9CDD4;
      --border-light: rgba(0,0,0,0.04);
      --shadow-card: 0 4px 12px rgba(0, 0, 0, 0.04), 0 1px 2px rgba(0, 0, 0, 0.02);
      --shadow-card-hover: 0 12px 24px rgba(0, 0, 0, 0.06);
      --radius-md: 12px;
      --radius-full: 50px;
      --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
      --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Inter", sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-base);
      color: var(--text-primary);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 16px;
      }
    }
    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,0,0,0.05);
      z-index: 1000;
      height: 72px;
      display: flex;
      align-items: center;
      transition: var(--transition);
    }
    .nav {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--text-primary);
      text-decoration: none;
      letter-spacing: -0.5px;
    }
    .logo span {
      color: var(--primary);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 2.5rem;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 0.95rem;
      transition: var(--transition);
      position: relative;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-cta {
      background: var(--primary);
      color: white !important;
      padding: 0.6rem 1.8rem;
      border-radius: var(--radius-full);
      font-weight: 600;
      box-shadow: 0 2px 8px rgba(78,110,242,0.3);
    }
    .nav-cta:hover {
      background: #3A5AD9;
      transform: translateY(-1px);
      box-shadow: 0 6px 16px rgba(78,110,242,0.4);
    }
    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--text-primary);
      cursor: pointer;
    }
    @media (max-width: 1024px) {
      .nav-links {
        gap: 1.8rem;
      }
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 2rem;
        box-shadow: 0 10px 20px rgba(0,0,0,0.05);
        gap: 1.5rem;
        align-items: flex-start;
      }
      .nav-links.active-mobile {
        display: flex;
      }
      .mobile-menu-btn {
        display: block;
      }
    }
    /* 区块通用 */
    section {
      padding: 100px 0;
      scroll-margin-top: 72px;
    }
    @media (max-width: 768px) {
      section {
        padding: 70px 0;
      }
    }
    .section-title {
      font-size: 2.25rem;
      font-weight: 600;
      margin-bottom: 1rem;
      letter-spacing: -0.5px;
    }
    .section-sub {
      color: var(--text-secondary);
      font-size: 1.1rem;
      max-width: 600px;
      margin: 0 auto 3rem auto;
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, #ffffff 0%, #f0f3fc 100%);
      padding-top: 120px;
      min-height: 90vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
    }
    .hero-left h1 {
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }
    .hero-left .highlight {
      color: var(--primary);
      position: relative;
    }
    .hero-desc {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 2.5rem;
      max-width: 500px;
    }
    .hero-btns {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-block;
      padding: 0.8rem 2rem;
      border-radius: var(--radius-full);
      font-weight: 600;
      text-decoration: none;
      transition: var(--transition);
      cursor: pointer;
      border: none;
      font-size: 1rem;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      box-shadow: 0 6px 18px rgba(78,110,242,0.3);
    }
    .btn-primary:hover {
      background: #3A5AD9;
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background: var(--primary-light);
    }
    .hero-right {
      display: flex;
      justify-content: center;
      align-items: center;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 400px;
      border-radius: 32px;
      position: relative;
      overflow: hidden;
    }
    .hero-abstract {
      width: 100%;
      height: 100%;
      background: rgba(255,255,255,0.25);
      backdrop-filter: blur(4px);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 6rem;
      color: var(--primary);
      opacity: 0.9;
    }
    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .hero-left h1 {
        font-size: 2.2rem;
      }
      .hero-right {
        min-height: 250px;
      }
    }
    /* 核心优势 */
    .advantages {
      background: var(--bg-white);
    }
    .adv-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    .adv-item {
      text-align: left;
      padding: 2rem;
      background: var(--bg-base);
      border-radius: var(--radius-md);
      transition: var(--transition);
    }
    .adv-item:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    .adv-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--primary);
      line-height: 1;
      margin-bottom: 1rem;
    }
    .adv-item h3 {
      font-size: 1.4rem;
      margin-bottom: 0.6rem;
    }
    @media (max-width: 768px) {
      .adv-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 解决方案卡片 */
    .solutions {
      background: var(--bg-base);
    }
    .card-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    .card {
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-card-hover);
    }
    .card-img {
      height: 200px;
      background-size: cover;
      background-position: center;
    }
    .card-body {
      padding: 1.8rem;
    }
    .card-body h3 {
      margin-bottom: 0.8rem;
    }
    .card-body p {
      color: var(--text-secondary);
      margin-bottom: 1.2rem;
    }
    .text-link {
      color: var(--primary);
      font-weight: 600;
      text-decoration: none;
    }
    @media (max-width: 1024px) {
      .card-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 768px) {
      .card-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 案例 */
    .cases {
      background: var(--bg-white);
    }
    .case-layout {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
    }
    .case-image {
      background: url('/assets/images/coverpic/cover-1.webp') center/cover no-repeat;
      min-height: 320px;
      border-radius: var(--radius-md);
    }
    .case-details p {
      margin-bottom: 1rem;
    }
    @media (max-width: 768px) {
      .case-layout {
        grid-template-columns: 1fr;
      }
    }
    /* 方案对比 */
    .compare {
      background: var(--bg-base);
    }
    .compare-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    .compare-card {
      background: white;
      border-radius: var(--radius-md);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      border: 2px solid transparent;
    }
    .compare-card.featured {
      border-color: var(--primary);
      background: #f8faff;
    }
    .compare-card h3 {
      margin-bottom: 1rem;
    }
    .price {
      font-size: 2rem;
      font-weight: 700;
      margin: 1rem 0;
    }
    @media (max-width: 768px) {
      .compare-grid {
        grid-template-columns: 1fr;
      }
    }
    /* FAQ */
    .faq {
      background: var(--bg-white);
    }
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid #eee;
      padding: 1.2rem 0;
    }
    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
      margin-top: 0.5rem;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
    }
    /* CTA 尾屏 */
    .cta-full {
      background: var(--bg-dark);
      color: white;
      text-align: center;
    }
    .cta-full h2 {
      font-size: 2.5rem;
      margin-bottom: 1rem;
    }
    .btn-large {
      padding: 1rem 2.8rem;
      font-size: 1.2rem;
    }
    /* 页脚 */
    .footer {
      background: var(--bg-dark);
      color: var(--text-secondary);
      padding: 3rem 0;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
    }
    .footer a {
      color: var(--text-secondary);
      text-decoration: none;
    }
    .footer a:hover {
      color: var(--primary);
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }