/* roulang page: index */
/* ----- 设计变量 & reset ----- */
    :root {
      --primary: #1A6DF5;
      --primary-dark: #1557D0;
      --accent: #0FCF97;
      --accent-dark: #0BB87E;
      --deep-gray: #1E2A3A;
      --body-text: #4B5563;
      --white: #FFFFFF;
      --bg-light: #F8FAFC;
      --bg-data: #F0F4F8;
      --border: #E5E7EB;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.06), 0 4px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 24px rgba(26,109,245,0.12), 0 2px 6px rgba(0,0,0,0.06);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-mono: "Inter", "SF Mono", "Menlo", monospace;
    }
    * { box-sizing: border-box; margin: 0; padding: 0; }
    html { scroll-behavior: smooth; }
    body {
      font-family: var(--font-sans);
      font-size: 15px;
      line-height: 1.7;
      color: var(--body-text);
      background: var(--white);
      -webkit-font-smoothing: antialiased;
    }
    img { max-width: 100%; height: auto; display: block; }
    a { text-decoration: none; color: inherit; }
    button, .btn { cursor: pointer; font-family: inherit; }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 32px;
    }
    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
    }
    @media (max-width: 640px) {
      .container { padding: 0 16px; }
    }

    /* ----- 导航 ----- */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      z-index: 1000;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid transparent;
      transition: background 0.25s, box-shadow 0.25s;
      display: flex;
      align-items: center;
    }
    .site-header.scrolled {
      background: var(--white);
      box-shadow: 0 1px 8px rgba(0,0,0,0.06);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 20px;
      font-weight: 700;
      color: var(--deep-gray);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo-icon {
      width: 28px;
      height: 28px;
      background: var(--primary);
      border-radius: 6px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 16px;
      font-weight: 700;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }
    .nav-menu a {
      font-size: 15px;
      font-weight: 500;
      color: var(--body-text);
      padding: 6px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }
    .nav-cta-btn {
      background: var(--primary);
      color: white !important;
      padding: 10px 20px !important;
      border-radius: 20px;
      font-weight: 600;
      font-size: 14px;
      border-bottom: none !important;
      transition: background 0.25s;
    }
    .nav-cta-btn:hover {
      background: var(--primary-dark);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      width: 28px;
      cursor: pointer;
    }
    .hamburger span {
      width: 100%;
      height: 2px;
      background: var(--deep-gray);
      border-radius: 4px;
      transition: 0.2s;
    }
    @media (max-width: 1024px) {
      .nav-menu {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        align-items: center;
        padding: 32px 0;
        gap: 24px;
        box-shadow: 0 10px 20px rgba(0,0,0,0.05);
        transform: translateY(-120%);
        opacity: 0;
        transition: 0.3s ease;
        pointer-events: none;
      }
      .nav-menu.open {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
      }
      .hamburger { display: flex; }
    }
    @media (max-width: 640px) {
      .site-header { height: 60px; }
      .nav-menu { top: 60px; }
    }

    /* 板块通用 */
    section {
      padding: 80px 0;
    }
    @media (max-width: 640px) {
      section { padding: 60px 0; }
    }
    .section-title {
      font-size: 28px;
      font-weight: 700;
      color: var(--deep-gray);
      text-align: center;
      margin-bottom: 16px;
    }
    .section-sub {
      text-align: center;
      color: var(--body-text);
      max-width: 600px;
      margin: 0 auto 48px;
    }

    /* Hero */
    .hero {
      min-height: 85vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #F0F4F8 0%, #FFFFFF 100%);
      padding-top: 100px;
      position: relative;
      overflow: hidden;
    }
    .hero-bg-img {
      position: absolute;
      right: -10%;
      top: 0;
      width: 55%;
      height: 100%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      opacity: 0.35;
      pointer-events: none;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 600px;
    }
    .hero h1 {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
      color: var(--deep-gray);
      margin-bottom: 20px;
    }
    .hero h1 span {
      color: var(--primary);
    }
    .hero p {
      font-size: 18px;
      color: var(--body-text);
      margin-bottom: 32px;
      max-width: 520px;
    }
    .hero-btns {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border: none;
      transition: 0.25s;
      display: inline-flex;
      align-items: center;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      box-shadow: 0 8px 16px rgba(26,109,245,0.25);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 14px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.25s;
    }
    .btn-outline:hover {
      background: rgba(26,109,245,0.05);
    }
    @media (max-width: 640px) {
      .hero h1 { font-size: 26px; }
      .hero-bg-img { width: 80%; right: -30%; }
      .hero-btns .btn-primary, .hero-btns .btn-outline { width: 100%; justify-content: center; }
    }

    /* 数据看板 */
    .metrics {
      background: var(--bg-data);
    }
    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .metric-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px;
      text-align: center;
      box-shadow: var(--shadow-card);
    }
    .metric-num {
      font-family: var(--font-mono);
      font-size: 40px;
      font-weight: 700;
      color: var(--primary);
    }
    .metric-label {
      font-size: 13px;
      color: var(--body-text);
      margin-top: 8px;
    }
    @media (max-width: 640px) {
      .metrics-grid { grid-template-columns: 1fr 1fr; }
    }

    /* 服务矩阵 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      border: 1px solid var(--border);
      box-shadow: var(--shadow-card);
      transition: 0.3s;
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: var(--primary);
    }
    .service-icon {
      width: 64px;
      height: 64px;
      margin-bottom: 20px;
      border-radius: 12px;
      background: #F0F4F8;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .service-card h3 {
      font-size: 20px;
      font-weight: 600;
      color: var(--deep-gray);
      margin-bottom: 10px;
    }
    .service-card p {
      font-size: 15px;
      margin-bottom: 16px;
    }
    .service-link {
      color: var(--primary);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }
    @media (max-width: 768px) {
      .services-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 640px) {
      .services-grid { grid-template-columns: 1fr; }
    }

    /* 对比表 */
    .compare-wrapper {
      display: flex;
      gap: 32px;
      align-items: center;
      justify-content: center;
    }
    .compare-col {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      flex: 1;
      border: 1px solid var(--border);
    }
    .compare-col h3 {
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 24px;
    }
    .compare-item {
      display: flex;
      justify-content: space-between;
      padding: 12px 0;
      border-bottom: 1px solid var(--border);
    }
    .check { color: var(--accent); font-weight: bold; }
    .cross { color: #e07b7b; }
    .vs-badge {
      background: var(--primary);
      color: white;
      border-radius: 50%;
      width: 56px;
      height: 56px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 18px;
    }
    @media (max-width: 768px) {
      .compare-wrapper { flex-direction: column; }
      .vs-badge { margin: 8px 0; }
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-card);
      transition: 0.2s;
    }
    .case-card:hover { transform: translateY(-4px); }
    .case-img {
      height: 120px;
      background: #F0F4F8;
      border-radius: 8px;
      margin-bottom: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
    }
    .case-stat {
      font-size: 32px;
      font-weight: 700;
      color: var(--accent);
    }
    @media (max-width: 768px) {
      .cases-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 640px) {
      .cases-grid { grid-template-columns: 1fr; }
    }

    /* FAQ */
    .faq {
      background: var(--bg-light);
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      border: 1px solid var(--border);
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 20px 24px;
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      font-size: 17px;
      color: var(--deep-gray);
      cursor: pointer;
    }
    .faq-answer {
      padding: 0 24px 20px;
      display: none;
      color: var(--body-text);
    }
    .faq-item.open .faq-answer { display: block; }
    .faq-item.open .faq-question { color: var(--primary); }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #1A6DF5, #1557D0);
      text-align: center;
      color: white;
      padding: 80px 0;
    }
    .cta-section h2 {
      color: white;
      font-size: 28px;
      margin-bottom: 16px;
    }
    .cta-btns {
      display: flex;
      gap: 16px;
      justify-content: center;
      margin-top: 28px;
    }
    .btn-white {
      background: white;
      color: var(--primary);
      padding: 16px 36px;
      border-radius: var(--radius-btn);
      font-weight: 700;
    }
    .btn-ghost {
      border: 2px solid white;
      color: white;
      padding: 16px 36px;
      border-radius: var(--radius-btn);
    }
    @media (max-width: 640px) {
      .cta-btns { flex-direction: column; align-items: center; }
    }

    /* Footer */
    .footer {
      background: var(--deep-gray);
      color: #CBD5E1;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a { color: #CBD5E1; }
    .footer a:hover { color: white; }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }