/* roulang page: index */
:root {
      --color-primary: #E8453C;
      --color-primary-dark: #c5302a;
      --color-secondary: #1A1A2E;
      --color-accent: #FFB347;
      --color-accent-dark: #F59E2E;
      --color-bg: #F5F0EB;
      --color-card: #FFFFFF;
      --color-text: #4A4A5A;
      --color-text-light: #FEFEFE;
      --color-border: #E8E3DE;
      --color-footer-bg: #151525;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --shadow-card: 0 2px 8px rgba(26,26,46,0.04);
      --shadow-card-hover: 0 4px 20px rgba(26,26,46,0.06);
      --shadow-btn: 0 4px 14px rgba(232,69,60,0.3);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", -apple-system, sans-serif;
      --font-number: "Inter", "SF Pro Display", -apple-system, sans-serif;
      --transition: all 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(--color-bg);
      color: var(--color-text);
      line-height: 1.8;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

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

    a, button, input, textarea {
      font-family: inherit;
    }

    a {
      text-decoration: none;
      color: inherit;
    }

    button {
      cursor: pointer;
      border: none;
      background: none;
    }

    .container {
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
    }

    @media (min-width: 1024px) {
      .container {
        padding-left: 40px;
        padding-right: 40px;
      }
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(8px);
      z-index: 1000;
      height: 72px;
      display: flex;
      align-items: center;
      transition: var(--transition);
      box-shadow: 0 1px 0 transparent;
    }

    .site-header.scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
      background: rgba(255,255,255,0.98);
    }

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

    .logo {
      display: flex;
      align-items: baseline;
      gap: 8px;
    }

    .logo a {
      font-size: 1.5rem;
      font-weight: 700;
      letter-spacing: -0.02em;
      color: var(--color-secondary);
      white-space: nowrap;
    }

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

    .logo .domain-hint {
      font-size: 0.7rem;
      color: var(--color-text);
      opacity: 0.7;
      font-weight: 400;
      letter-spacing: 0.02em;
      margin-top: 4px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }

    .nav-links a {
      font-size: 0.9rem;
      font-weight: 500;
      color: var(--color-text);
      transition: var(--transition);
      position: relative;
      padding: 6px 0;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--color-primary);
    }

    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 100%;
      height: 3px;
      background: var(--color-primary);
      border-radius: 2px;
    }

    .btn-nav {
      background: var(--color-accent);
      color: var(--color-secondary) !important;
      font-weight: 600;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-size: 0.9rem;
      transition: var(--transition);
      margin-left: 8px;
      white-space: nowrap;
    }

    .btn-nav:hover {
      background: var(--color-accent-dark);
      box-shadow: 0 4px 10px rgba(255,179,71,0.35);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      padding: 8px;
    }

    .hamburger span {
      display: block;
      width: 24px;
      height: 2px;
      background: var(--color-secondary);
      transition: var(--transition);
    }

    @media (max-width: 1023px) {
      .nav-links {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(12px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 32px;
        z-index: 999;
      }

      .nav-links.open {
        display: flex;
      }

      .hamburger {
        display: flex;
      }

      .site-header {
        height: 60px;
      }
    }

    /* 板块间距 */
    section {
      padding: 80px 0;
    }

    @media (max-width: 640px) {
      section {
        padding: 60px 0;
      }
    }

    /* Hero */
    .hero {
      position: relative;
      background: var(--color-secondary);
      min-height: 85vh;
      display: flex;
      align-items: center;
      overflow: hidden;
      margin-top: 72px;
    }

    .hero-bg {
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center 30%;
      opacity: 0.35;
      z-index: 0;
    }

    .hero-content {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      gap: 40px;
      width: 100%;
    }

    .hero-text {
      flex: 1 1 50%;
    }

    .hero-visual {
      flex: 1 1 45%;
      display: flex;
      justify-content: center;
    }

    .hero-visual img {
      border-radius: 24px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.25);
      max-height: 420px;
      object-fit: cover;
    }

    .hero h1 {
      font-size: clamp(2rem, 6vw, 3.2rem);
      font-weight: 700;
      color: var(--color-text-light);
      line-height: 1.2;
      margin-bottom: 1.5rem;
      letter-spacing: -0.02em;
    }

    .hero h1 span {
      color: var(--color-accent);
    }

    .hero-desc {
      font-size: 1.15rem;
      color: rgba(255,255,255,0.85);
      margin-bottom: 2rem;
      max-width: 520px;
    }

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

    .btn-primary {
      background: var(--color-accent);
      color: var(--color-secondary);
      font-weight: 700;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-size: 1rem;
      letter-spacing: 0.04em;
      box-shadow: var(--shadow-btn);
      transition: var(--transition);
    }

    .btn-primary:hover {
      background: var(--color-accent-dark);
      box-shadow: 0 8px 20px rgba(255,179,71,0.4);
    }

    .btn-outline {
      border: 2px solid var(--color-primary);
      color: var(--color-text-light);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      transition: var(--transition);
      background: transparent;
    }

    .btn-outline:hover {
      background: rgba(232,69,60,0.1);
    }

    @media (max-width: 1023px) {
      .hero-content {
        flex-direction: column;
        text-align: center;
      }
      .hero-visual img {
        max-width: 80%;
        margin-top: 24px;
      }
      .hero-desc {
        margin-left: auto;
        margin-right: auto;
      }
      .hero-buttons {
        justify-content: center;
      }
    }

    @media (min-width: 1024px) {
      .hero {
        min-height: 90vh;
      }
      .hero-text {
        padding-right: 20px;
      }
    }

    /* 优势 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      margin-top: 40px;
    }

    .adv-card {
      background: var(--color-card);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }

    .adv-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }

    .adv-icon {
      font-size: 2.5rem;
      margin-bottom: 16px;
    }

    .adv-card h3 {
      font-weight: 700;
      margin-bottom: 12px;
      color: var(--color-secondary);
    }

    @media (max-width: 768px) {
      .advantages-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 服务矩阵 2x3 大小卡混排 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .service-card {
      background: var(--color-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }

    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
      border-top: 3px solid var(--color-primary);
    }

    .service-img {
      height: 180px;
      background-size: cover;
      background-position: center;
    }

    .service-body {
      padding: 24px;
    }

    .service-body h3 {
      font-weight: 700;
      color: var(--color-secondary);
      margin-bottom: 10px;
    }

    .text-link {
      color: var(--color-primary);
      font-weight: 600;
      font-size: 0.95rem;
      display: inline-block;
      margin-top: 12px;
    }

    @media (max-width: 768px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 数据 */
    .stats {
      background: linear-gradient(90deg, rgba(232,69,60,0.08) 0%, rgba(232,69,60,0.02) 100%);
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      text-align: center;
      gap: 24px;
    }

    .stat-item {
      padding: 20px;
    }

    .stat-number {
      font-size: 3rem;
      font-weight: 700;
      color: var(--color-primary);
      font-family: var(--font-number);
    }

    .stat-label {
      color: var(--color-text);
      font-weight: 500;
    }

    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      margin-top: 40px;
    }

    .case-card {
      background: var(--color-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      position: relative;
    }

    .case-card:hover {
      transform: translateY(-4px);
    }

    .case-img {
      height: 200px;
      background-size: cover;
      background-position: center;
    }

    .case-tag {
      position: absolute;
      top: 16px;
      left: 16px;
      background: var(--color-primary);
      color: white;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
    }

    .case-body {
      padding: 22px;
    }

    @media (max-width: 768px) {
      .cases-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 方案图文交替 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }

    .solution-row.reverse {
      flex-direction: row-reverse;
    }

    .solution-img {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      background-size: cover;
      background-position: center;
      min-height: 280px;
    }

    .solution-text {
      flex: 1;
    }

    @media (max-width: 1023px) {
      .solution-row, .solution-row.reverse {
        flex-direction: column;
      }
      .solution-img {
        width: 100%;
      }
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 40px auto 0;
    }

    .faq-item {
      background: var(--color-card);
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      box-shadow: var(--shadow-card);
    }

    .faq-question {
      width: 100%;
      text-align: left;
      padding: 20px 24px;
      font-weight: 700;
      font-size: 1rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--color-secondary);
      border-left: 4px solid var(--color-primary);
      transition: var(--transition);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 24px;
      color: var(--color-text);
    }

    .faq-item.open .faq-answer {
      max-height: 200px;
      padding: 0 24px 20px;
    }

    .faq-item.open .faq-question {
      border-left-color: var(--color-accent);
    }

    /* CTA */
    .cta-global {
      background: var(--color-secondary);
      text-align: center;
      padding: 80px 20px;
    }

    .cta-global h2 {
      color: white;
      font-size: 2.2rem;
    }

    .cta-global .btn-primary {
      margin-top: 24px;
    }

    /* Footer */
    .site-footer {
      background: var(--color-footer-bg);
      color: #ccc;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }

    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }

    .footer-bottom {
      border-top: 1px solid #2a2a3a;
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 0.85rem;
    }

    h2 {
      font-size: 2rem;
      font-weight: 700;
      color: var(--color-secondary);
      margin-bottom: 20px;
    }

    @media (max-width: 640px) {
      h2 {
        font-size: 1.6rem;
      }
    }

    button:focus-visible, a:focus-visible {
      outline: 2px solid var(--color-primary);
      outline-offset: 2px;
    }