/* roulang page: index */
:root {
      --primary: #1E1E24;
      --accent: #F15A24;
      --accent-hover: #D94A1A;
      --bg-warm: #FAF9F7;
      --bg-light: #F0EDE8;
      --text-primary: #1E1E24;
      --text-secondary: #5A5753;
      --text-muted: #8A8580;
      --white: #FFFFFF;
      --border-light: #E5E0DA;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.08), 0 2px 6px rgba(0,0,0,0.06);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-number: 'Inter', 'SF Pro Display', system-ui, sans-serif;
      --max-width: 1280px;
      --header-height: 72px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-body);
      background-color: var(--bg-warm);
      color: var(--text-primary);
      line-height: 1.7;
      font-weight: 400;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(250, 249, 247, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 1000;
      transition: background 0.3s ease, box-shadow 0.3s ease;
      border-bottom: 1px solid transparent;
    }
    .header.scrolled {
      background: rgba(250, 249, 247, 0.98);
      box-shadow: 0 1px 8px rgba(0,0,0,0.04);
      border-bottom: 1px solid var(--border-light);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 1.6rem;
      color: var(--primary);
      text-decoration: none;
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo-dot {
      display: inline-block;
      width: 8px;
      height: 8px;
      background: var(--accent);
      border-radius: 50%;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-link {
      font-weight: 500;
      color: var(--text-primary);
      text-decoration: none;
      font-size: 0.95rem;
      position: relative;
      padding: 8px 0;
      transition: color 0.2s;
      white-space: nowrap;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.25s ease;
    }
    .nav-link:hover,
    .nav-link.active {
      color: var(--accent);
    }
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--accent);
      color: var(--white);
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: none;
      cursor: pointer;
      font-size: 0.95rem;
      transition: background 0.25s ease, transform 0.25s ease;
      white-space: nowrap;
      letter-spacing: 0.3px;
      box-shadow: 0 4px 10px rgba(241, 90, 36, 0.2);
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      transform: scale(1.03);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: all 0.25s ease;
      white-space: nowrap;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: var(--white);
      border-color: var(--primary);
    }
    .btn-outline-white {
      border-color: var(--white);
      color: var(--white);
    }
    .btn-outline-white:hover {
      background: var(--white);
      color: var(--primary);
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      cursor: pointer;
      padding: 8px;
      flex-direction: column;
      gap: 5px;
      z-index: 1001;
    }
    .hamburger span {
      display: block;
      width: 24px;
      height: 2px;
      background: var(--primary);
      transition: 0.3s;
      border-radius: 2px;
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      right: 0;
      width: 100%;
      height: 100vh;
      background: var(--bg-warm);
      transform: translateX(100%);
      transition: transform 0.4s cubic-bezier(0.23, 1, 0.32, 1);
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 32px;
      z-index: 999;
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-menu a {
      font-size: 1.5rem;
      font-weight: 600;
      color: var(--primary);
      text-decoration: none;
    }
    /* 区块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: clamp(2.2rem, 5vw, 2.8rem);
      color: var(--primary);
      margin-bottom: 16px;
      letter-spacing: -0.3px;
    }
    .section-desc {
      color: var(--text-secondary);
      font-size: 1.1rem;
      max-width: 680px;
      margin-bottom: 48px;
    }
    /* Hero */
    .hero {
      padding-top: calc(var(--header-height) + 60px);
      padding-bottom: 80px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 6fr 7fr;
      gap: 48px;
      align-items: center;
    }
    .hero-title {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: clamp(2.8rem, 6vw, 3.8rem);
      line-height: 1.15;
      color: var(--primary);
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 1.15rem;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 420px;
      line-height: 1.6;
    }
    .hero-btns {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-visual {
      position: relative;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.12);
    }
    .hero-visual img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
      aspect-ratio: 4/3;
      transition: transform 0.4s ease;
    }
    .hero-visual:hover img {
      transform: scale(1.02);
    }
    /* 优势网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .feature-card {
      background: var(--bg-light);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      transition: all 0.3s ease;
      box-shadow: var(--shadow-card);
      text-align: left;
    }
    .feature-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-4px);
    }
    .feature-icon {
      font-size: 2.5rem;
      color: var(--accent);
      margin-bottom: 16px;
      display: inline-block;
      transition: transform 0.3s;
    }
    .feature-card:hover .feature-icon {
      transform: rotate(5deg);
    }
    .feature-card h3 {
      font-family: var(--font-title);
      font-weight: 650;
      font-size: 1.3rem;
      margin-bottom: 8px;
      color: var(--primary);
    }
    .feature-card p {
      color: var(--text-secondary);
      font-size: 0.95rem;
      line-height: 1.5;
    }
    /* 案例瀑布 */
    .cases-masonry {
      columns: 3;
      column-gap: 24px;
    }
    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: all 0.35s ease;
    }
    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-card-hover);
    }
    .case-card img {
      width: 100%;
      display: block;
      transition: filter 0.4s ease, transform 0.4s;
    }
    .case-card:hover img {
      filter: saturate(1.15);
      transform: scale(1.03);
    }
    .case-info {
      padding: 20px;
    }
    .case-info h3 {
      font-family: var(--font-title);
      font-weight: 650;
      font-size: 1.2rem;
      margin-bottom: 8px;
    }
    .case-tag {
      background: var(--bg-light);
      color: var(--accent);
      font-size: 0.75rem;
      font-weight: 600;
      padding: 4px 10px;
      border-radius: var(--radius-tag);
      display: inline-block;
      margin-bottom: 8px;
    }
    .case-quote {
      color: var(--text-muted);
      font-size: 0.9rem;
      line-height: 1.5;
    }
    /* 方案对比 */
    .solutions-table {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
    }
    .solution-col {
      background: var(--white);
      border-radius: var(--radius-card);
      border: 1px solid var(--border-light);
      padding: 32px 24px;
      transition: all 0.3s;
    }
    .solution-col:hover {
      border-color: var(--accent);
      box-shadow: var(--shadow-card-hover);
    }
    .solution-col h3 {
      font-weight: 700;
      font-size: 1.4rem;
      margin-bottom: 12px;
    }
    .solution-list {
      list-style: none;
      margin: 20px 0;
    }
    .solution-list li {
      padding: 8px 0;
      color: var(--text-secondary);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .solution-list li::before {
      content: "✓";
      color: var(--accent);
      font-weight: bold;
    }
    /* 信任数据 */
    .trust-bg {
      background: var(--primary);
      color: var(--white);
    }
    .trust-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }
    .trust-item .number {
      font-family: var(--font-number);
      font-weight: 700;
      font-size: 3.4rem;
      color: var(--accent);
      line-height: 1.1;
    }
    .trust-item .label {
      color: rgba(255,255,255,0.8);
      margin-top: 8px;
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 650;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      background: none;
      border: none;
      width: 100%;
      text-align: left;
      color: var(--primary);
      transition: 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    .faq-icon {
      font-size: 1.5rem;
      color: var(--accent);
    }
    /* CTA */
    .cta-section {
      background: var(--primary);
      text-align: center;
    }
    .cta-title {
      color: var(--white);
      font-size: 2.5rem;
      font-weight: 700;
    }
    .cta-desc {
      color: rgba(255,255,255,0.75);
      margin: 20px 0 32px;
    }
    .cta-btns {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
    }
    /* Footer */
    .footer {
      background: var(--primary);
      color: rgba(255,255,255,0.7);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer-logo {
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--white);
      margin-bottom: 12px;
    }
    .footer a {
      color: rgba(255,255,255,0.7);
      text-decoration: none;
      transition: color 0.2s;
    }
    .footer a:hover {
      color: var(--white);
    }
    .copyright {
      margin-top: 40px;
      text-align: center;
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 24px;
      font-size: 0.9rem;
    }
    @media (max-width: 1024px) {
      .hero-grid { grid-template-columns: 1fr; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .cases-masonry { columns: 2; }
      .solutions-table { grid-template-columns: 1fr; }
      .trust-grid { grid-template-columns: repeat(2,1fr); }
      .footer-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .features-grid { grid-template-columns: 1fr; }
      .cases-masonry { columns: 1; }
      .trust-grid { grid-template-columns: 1fr 1fr; }
    }