/* roulang page: index */
:root {
      --primary: #F15A24;
      --primary-dark: #D94A1A;
      --secondary: #1A1A1A;
      --bg: #FAF9F7;
      --surface: #FFFFFF;
      --green-accent: #2E7D32;
      --text-primary: #1A1A1A;
      --text-body: #3D3D3D;
      --text-muted: #6B6B6B;
      --text-light: #9B9B9B;
      --border-light: #E8E6E1;
      --border-warm: #F0EDE8;
      --shadow-card: 0 2px 12px rgba(26,26,26,0.04);
      --shadow-card-hover: 0 8px 28px rgba(26,26,26,0.08);
      --radius-sm: 6px;
      --radius-md: 8px;
      --radius-lg: 12px;
      --radius-pill: 40px;
      --font-title: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-mono: "Inter", "SF Pro Display", "Helvetica Neue", sans-serif;
      --max-width: 1280px;
      --spacing-section: 120px;
      --spacing-element: 32px;
      --transition-base: 0.25s cubic-bezier(0.22, 0.61, 0.36, 1);
      --transition-smooth: 0.4s ease-in-out;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-title);
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      letter-spacing: 0.01em;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 40px;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-title);
      color: var(--text-primary);
      letter-spacing: -0.02em;
      line-height: 1.2;
    }

    h1 {
      font-size: 56px;
      font-weight: 700;
    }

    h2 {
      font-size: 40px;
      font-weight: 700;
      margin-bottom: 16px;
    }

    h3 {
      font-size: 22px;
      font-weight: 600;
    }

    h4 {
      font-size: 18px;
      font-weight: 600;
    }

    p {
      font-size: 17px;
      color: var(--text-body);
      margin-bottom: 16px;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition-base);
    }

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

    button, .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-family: var(--font-title);
      font-weight: 600;
      border-radius: var(--radius-md);
      cursor: pointer;
      transition: all var(--transition-base);
      border: none;
      font-size: 17px;
      padding: 14px 32px;
      line-height: 1.2;
      gap: 8px;
      letter-spacing: 0.02em;
    }

    .btn-primary {
      background: var(--primary);
      color: #FFFFFF;
      box-shadow: 0 4px 12px rgba(241,90,36,0.15);
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(241,90,36,0.25);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--secondary);
      color: var(--secondary);
    }

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

    .btn-white {
      background: #FFFFFF;
      color: var(--secondary);
      border: 1px solid var(--border-light);
    }

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

    /* 导航栏 PC */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      right: 0;
      height: 72px;
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(8px);
      border-bottom: 1px solid var(--border-light);
      z-index: 1000;
      display: flex;
      align-items: center;
      padding: 0 40px;
      transition: box-shadow 0.3s ease;
    }

    .navbar.scrolled {
      box-shadow: 0 2px 20px rgba(0,0,0,0.04);
    }

    .nav-container {
      max-width: var(--max-width);
      width: 100%;
      margin: 0 auto;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .logo {
      display: flex;
      align-items: baseline;
      gap: 6px;
      font-weight: 800;
      font-size: 24px;
      color: var(--secondary);
      letter-spacing: -0.01em;
    }

    .logo .domain {
      font-size: 14px;
      font-weight: 400;
      color: var(--text-muted);
      letter-spacing: 0.02em;
    }

    .nav-links {
      display: flex;
      gap: 36px;
      list-style: none;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-body);
      position: relative;
      padding: 4px 0;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition-base);
    }

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

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

    /* 移动端底部导航 */
    .mobile-nav {
      display: none;
    }

    /* Hero */
    .hero {
      padding-top: 160px;
      padding-bottom: 100px;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }

    .hero-left {
      display: flex;
      flex-direction: column;
      justify-content: center;
    }

    .hero-left h1 {
      margin-bottom: 20px;
      line-height: 1.15;
    }

    .hero-left .subtitle {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 36px;
      max-width: 80%;
    }

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

    .hero-right {
      position: relative;
    }

    .hero-image-wrapper {
      border-radius: var(--radius-lg);
      overflow: hidden;
      clip-path: polygon(3% 0%, 100% 0%, 97% 100%, 0% 100%);
      transform: rotate(0.5deg);
      transition: transform 0.3s ease;
      box-shadow: var(--shadow-card-hover);
    }

    .hero-image-wrapper img {
      width: 100%;
      height: auto;
      filter: grayscale(5%);
      transition: transform 0.4s ease;
    }

    .hero-right:hover .hero-image-wrapper img {
      transform: scale(1.02);
    }

    /* 板块通用 */
    .section {
      padding: var(--spacing-section) 0;
    }

    .section-header {
      text-align: center;
      margin-bottom: 60px;
    }

    .section-header h2 {
      margin-bottom: 12px;
    }

    .section-header .section-desc {
      font-size: 17px;
      color: var(--text-muted);
      max-width: 640px;
      margin: 0 auto;
    }

    /* 亮点网格 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }

    .highlight-card {
      background: var(--surface);
      padding: var(--spacing-element);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .highlight-card.wide {
      grid-column: span 2;
      flex-direction: row;
      align-items: center;
      background: #F5F3F0;
      gap: 32px;
    }

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

    .icon-circle {
      width: 48px;
      height: 48px;
      display: flex;
      align-items: center;
      justify-content: center;
      border: 1.5px solid var(--primary);
      border-radius: var(--radius-sm);
      color: var(--primary);
      font-size: 24px;
      flex-shrink: 0;
    }

    .highlight-card h3 {
      font-size: 20px;
    }

    .highlight-card p {
      font-size: 16px;
      color: var(--text-muted);
      margin: 0;
    }

    /* 案例瀑布 */
    .cases-waterfall {
      column-count: 3;
      column-gap: 24px;
    }

    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      background: var(--surface);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
    }

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

    .case-img {
      position: relative;
      overflow: hidden;
      aspect-ratio: 4/3;
    }

    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s ease;
    }

    .case-card:hover .case-img img {
      transform: scale(1.03);
    }

    .case-overlay {
      position: absolute;
      inset: 0;
      background: rgba(241,90,36,0);
      transition: background 0.3s ease;
    }

    .case-card:hover .case-overlay {
      background: rgba(241,90,36,0.12);
    }

    .case-info {
      padding: 20px;
    }

    .case-tag {
      font-size: 12px;
      letter-spacing: 0.08em;
      color: var(--primary);
      font-weight: 600;
      text-transform: uppercase;
      margin-bottom: 6px;
    }

    .case-info h3 {
      font-size: 17px;
      margin-bottom: 6px;
    }

    .case-info p {
      font-size: 14px;
      color: var(--text-muted);
      margin: 0;
    }

    /* 对比表 */
    .comparison-wrapper {
      max-width: 900px;
      margin: 0 auto;
    }

    .provocative-title {
      text-align: center;
      font-size: 28px;
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 48px;
    }

    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 0;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      overflow: hidden;
    }

    .compare-col {
      padding: 32px;
    }

    .compare-col.left {
      background: #F0EDE8;
    }

    .compare-col.right {
      background: #FFF3EE;
    }

    .compare-col h3 {
      margin-bottom: 24px;
      font-size: 24px;
    }

    .compare-row {
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 12px 0;
      border-bottom: 1px solid rgba(0,0,0,0.05);
      font-size: 16px;
    }

    .icon-x {
      color: #999;
      font-weight: 700;
    }

    .icon-check {
      color: var(--green-accent);
      font-weight: 700;
    }

    /* FAQ */
    .faq-list {
      max-width: 760px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 16px 0;
    }

    .faq-question {
      display: flex;
      align-items: center;
      gap: 16px;
      cursor: pointer;
      padding: 8px 0;
      transition: color 0.2s;
    }

    .faq-number {
      font-family: var(--font-mono);
      font-size: 28px;
      font-weight: 700;
      color: var(--primary);
      width: 48px;
      flex-shrink: 0;
    }

    .faq-question h4 {
      flex: 1;
      margin: 0;
    }

    .faq-arrow {
      font-size: 20px;
      transition: transform 0.4s ease;
    }

    .faq-item.active .faq-arrow {
      transform: rotate(180deg);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease-in-out;
      padding-left: 64px;
      color: var(--text-body);
      font-size: 16px;
      line-height: 1.8;
    }

    .faq-item.active .faq-answer {
      max-height: 300px;
      padding-bottom: 16px;
    }

    /* CTA */
    .cta-section {
      background-color: var(--secondary);
      background-image: repeating-linear-gradient(45deg, rgba(255,255,255,0.02) 0px, rgba(255,255,255,0.02) 2px, transparent 2px, transparent 8px);
      padding: 80px 0;
      text-align: center;
    }

    .cta-section h2 {
      color: #FFFFFF;
      font-size: 36px;
      margin-bottom: 24px;
    }

    .cta-form {
      display: flex;
      gap: 12px;
      max-width: 480px;
      margin: 0 auto 12px;
      flex-wrap: wrap;
      justify-content: center;
    }

    .cta-form input {
      flex: 2;
      min-width: 200px;
      padding: 14px 18px;
      border-radius: var(--radius-md);
      border: none;
      background: #FFFFFF;
      font-size: 16px;
      outline: none;
      transition: box-shadow 0.2s;
    }

    .cta-form input:focus {
      box-shadow: 0 0 0 3px rgba(241,90,36,0.4);
    }

    .cta-form button {
      flex: 1;
      background: var(--primary);
      color: #FFF;
      font-weight: 600;
      border: none;
      border-radius: var(--radius-md);
      padding: 14px 24px;
      cursor: pointer;
      transition: background 0.2s;
    }

    .cta-form button:hover {
      background: var(--primary-dark);
    }

    .privacy-note {
      color: #9B9B9B;
      font-size: 13px;
    }

    /* 页脚 */
    .footer {
      background: var(--bg);
      padding: 60px 0 30px;
      border-top: 1px solid var(--border-light);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 48px;
      margin-bottom: 40px;
    }

    .footer-col h4 {
      margin-bottom: 16px;
      font-size: 16px;
      color: var(--secondary);
    }

    .footer-col p, .footer-col a {
      font-size: 15px;
      color: var(--text-muted);
      display: block;
      margin-bottom: 8px;
    }

    .footer-col a:hover {
      color: var(--primary);
    }

    .copyright {
      text-align: center;
      font-size: 13px;
      color: var(--text-light);
      border-top: 1px solid var(--border-light);
      padding-top: 24px;
    }

    /* 滚动动画 */
    .fade-up {
      opacity: 0;
      transform: translateY(20px);
      transition: opacity 0.6s cubic-bezier(0.22, 0.61, 0.36, 1), transform 0.6s cubic-bezier(0.22, 0.61, 0.36, 1);
    }

    .fade-up.visible {
      opacity: 1;
      transform: translateY(0);
    }

    @media (max-width: 1024px) {
      .hero {
        grid-template-columns: 1fr;
        gap: 48px;
        text-align: center;
      }
      .hero-left .subtitle {
        max-width: 100%;
      }
      .hero-buttons {
        justify-content: center;
      }
      .highlights-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .highlight-card.wide {
        grid-column: span 2;
      }
      .cases-waterfall {
        column-count: 2;
      }
      h1 {
        font-size: 44px;
      }
    }

    @media (max-width: 768px) {
      .navbar {
        display: none;
      }
      .mobile-nav {
        display: flex;
        position: fixed;
        bottom: 20px;
        left: 50%;
        transform: translateX(-50%);
        background: rgba(255,255,255,0.92);
        backdrop-filter: blur(12px);
        border-radius: var(--radius-pill);
        padding: 8px 16px;
        box-shadow: 0 4px 24px rgba(0,0,0,0.08);
        z-index: 1000;
        gap: 8px;
      }
      .mobile-nav a {
        font-size: 13px;
        padding: 8px 14px;
        border-radius: 30px;
        color: var(--text-body);
        font-weight: 500;
        transition: 0.2s;
        white-space: nowrap;
      }
      .mobile-nav a.active {
        background: var(--primary);
        color: #FFFFFF;
      }
      .container {
        padding: 0 20px;
      }
      .hero {
        padding-top: 80px;
        padding-bottom: 60px;
      }
      h1 {
        font-size: 36px;
      }
      h2 {
        font-size: 30px;
      }
      .highlights-grid {
        grid-template-columns: 1fr;
      }
      .highlight-card.wide {
        grid-column: span 1;
        flex-direction: column;
      }
      .cases-waterfall {
        column-count: 1;
      }
      .compare-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .section {
        padding: 80px 0;
      }
    }