/* roulang page: index */
:root {
      --primary: #0A2E1F;
      --accent: #E85D04;
      --bg: #F9FAF8;
      --white: #FFFFFF;
      --text: #1A1A1A;
      --text-secondary: #5A5A5A;
      --border: #E0E0DE;
      --radius: 12px;
      --shadow: 0 2px 16px rgba(10,46,31,0.06);
      --shadow-hover: 0 8px 28px rgba(10,46,31,0.12);
      --transition: 0.3s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
      --container: 1280px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-sans);
      background: var(--bg);
      color: var(--text);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 24px;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      outline: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: var(--transition);
    }
    /* 导航 */
    .header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(12px);
      height: 72px;
      border-bottom: 1px solid var(--border);
      display: flex;
      align-items: center;
      padding: 0 24px;
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--container);
      margin: 0 auto;
    }
    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: -0.02em;
    }
    .logo-icon {
      width: 28px;
      height: 28px;
      background: var(--accent);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="white" stroke-width="2"><path d="M4 15s1-1 4-1 5 2 8 2 4-1 4-1V3s-1 1-4 1-5-2-8-2-4 1-4 1z"/><line x1="4" y1="22" x2="4" y2="15"/></svg>') center/contain no-repeat;
      background-color: var(--accent);
    }
    .nav-menu {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }
    .nav-link {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text);
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: var(--transition);
    }
    .nav-link:hover {
      color: var(--accent);
      border-bottom-color: var(--accent);
    }
    .active-nav {
      color: var(--accent);
      border-bottom-color: var(--accent);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--primary);
      transition: var(--transition);
    }
    /* 移动端导航 */
    @media (max-width: 767px) {
      .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        height: 100vh;
        background: var(--white);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 40px;
        transition: 0.3s ease;
        box-shadow: -5px 0 20px rgba(0,0,0,0.1);
        z-index: 60;
      }
      .nav-menu.active {
        right: 0;
      }
      .hamburger {
        display: flex;
        z-index: 70;
      }
      .close-btn {
        position: absolute;
        top: 24px;
        right: 24px;
        font-size: 2rem;
        background: none;
        border: none;
        color: var(--primary);
      }
    }
    /* 按钮 */
    .btn-primary {
      background: var(--accent);
      color: var(--white);
      border-radius: 8px;
      padding: 14px 32px;
      font-weight: 600;
      font-size: 1rem;
    }
    .btn-primary:hover {
      background: #C94D00;
      transform: scale(1.03);
    }
    .btn-secondary {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      border-radius: 8px;
      padding: 14px 32px;
      font-weight: 600;
      font-size: 1rem;
    }
    .btn-secondary:hover {
      background: var(--primary);
      color: var(--white);
    }
    .btn-white {
      background: white;
      color: var(--accent);
      border-radius: 8px;
      padding: 16px 40px;
      font-weight: 700;
      font-size: 1.1rem;
    }
    .btn-white:hover {
      background: var(--primary);
      color: white;
    }
    /* 区块标题 */
    .section-title {
      font-size: clamp(1.8rem, 3.5vw, 2.4rem);
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 16px;
      letter-spacing: -0.02em;
    }
    .title-decor {
      width: 40px;
      height: 4px;
      background: var(--accent);
      margin: 0 auto 24px;
    }
    .section-subtitle {
      font-size: 1.15rem;
      color: var(--text-secondary);
      margin-bottom: 48px;
      max-width: 700px;
    }
    /* Hero */
    #hero {
      padding: 80px 0 100px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero-content h1 {
      font-size: clamp(2.4rem, 5vw, 4rem);
      font-weight: 700;
      line-height: 1.15;
      color: var(--primary);
      margin-bottom: 24px;
    }
    .hero-content p {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .hero-image img {
      border-radius: 16px;
      box-shadow: var(--shadow);
      transition: 0.25s ease;
      object-fit: cover;
      width: 100%;
      aspect-ratio: 4/3;
    }
    .hero-image img:hover {
      transform: scale(1.02);
    }
    /* 优势网格 */
    #advantages {
      padding: 100px 0;
    }
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .advantage-card {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius);
      box-shadow: var(--shadow);
      transition: var(--transition);
    }
    .advantage-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .advantage-icon {
      width: 64px;
      height: 64px;
      margin-bottom: 24px;
      color: var(--accent);
      display: flex;
      align-items: center;
    }
    .advantage-card h3 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 12px;
    }
    /* 案例瀑布 */
    #cases {
      padding: 100px 0;
    }
    .cases-masonry {
      column-count: 3;
      column-gap: 20px;
      margin-top: 40px;
    }
    .case-card {
      break-inside: avoid;
      background: var(--white);
      border-radius: 8px;
      box-shadow: var(--shadow);
      margin-bottom: 20px;
      overflow: hidden;
      transition: var(--transition);
    }
    .case-card:hover {
      box-shadow: var(--shadow-hover);
    }
    .case-card img {
      width: 100%;
      display: block;
      transition: 0.25s ease;
    }
    .case-card:hover img {
      transform: scale(1.03);
    }
    .case-info {
      padding: 20px;
    }
    .case-info h3 {
      font-size: 1.2rem;
      font-weight: 600;
      margin-bottom: 8px;
    }
    /* 对比 */
    #comparison {
      padding: 100px 0;
    }
    .comparison-wrapper {
      display: grid;
      grid-template-columns: 1fr 40px 1fr;
      gap: 24px;
      align-items: start;
      margin-top: 40px;
    }
    .compare-card {
      background: var(--white);
      border-radius: var(--radius);
      padding: 40px 32px;
      box-shadow: var(--shadow);
    }
    .compare-highlight {
      background: var(--accent);
      color: white;
      writing-mode: vertical-rl;
      text-orientation: mixed;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 8px;
      font-weight: 700;
      letter-spacing: 0.1em;
      height: 100%;
      min-height: 200px;
    }
    .feature-list {
      list-style: none;
      margin-top: 24px;
    }
    .feature-list li {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 16px;
      font-size: 0.95rem;
    }
    .check {
      color: var(--primary);
      font-weight: bold;
    }
    .cross {
      color: #CCCCCC;
    }
    /* FAQ */
    #faq {
      background: var(--primary);
      padding: 100px 0;
      color: white;
    }
    #faq .section-title {
      color: white;
    }
    #faq .section-subtitle {
      color: #B0C4B8;
    }
    .faq-item {
      background: rgba(255,255,255,0.08);
      border-radius: 8px;
      margin-bottom: 12px;
      padding: 20px 24px;
      cursor: pointer;
      transition: var(--transition);
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
    }
    .faq-toggle {
      font-size: 1.4rem;
      color: var(--accent);
      transition: 0.3s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      color: #D0D8D2;
      padding-top: 0;
      border-top: 1px solid transparent;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-top: 16px;
      border-top-color: rgba(255,255,255,0.15);
    }
    /* CTA */
    #cta {
      background: var(--accent);
      text-align: center;
      padding: 80px 24px;
    }
    #cta h2 {
      color: white;
      font-size: 2.2rem;
      margin-bottom: 16px;
    }
    #cta p {
      color: rgba(255,255,255,0.9);
      margin-bottom: 32px;
    }
    /* 页脚 */
    #footer {
      background: var(--primary);
      color: #B0C4B8;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    .footer-logo {
      font-size: 1.3rem;
      font-weight: 700;
      color: white;
      margin-bottom: 12px;
    }
    .footer-links a {
      display: block;
      margin-bottom: 10px;
      color: #B0C4B8;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
      text-align: center;
      font-size: 0.8rem;
      color: #6A7A70;
    }
    /* 响应式 */
    @media (max-width: 1023px) {
      .hero-grid {
        grid-template-columns: 1fr;
        gap: 40px;
      }
      .advantages-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .cases-masonry {
        column-count: 2;
      }
      .comparison-wrapper {
        grid-template-columns: 1fr;
      }
      .compare-highlight {
        writing-mode: horizontal-tb;
        height: auto;
        padding: 12px;
      }
    }
    @media (max-width: 767px) {
      .advantages-grid {
        grid-template-columns: 1fr;
      }
      .cases-masonry {
        column-count: 1;
      }
      .hero-buttons {
        flex-direction: column;
      }
      .btn-primary, .btn-secondary {
        width: 100%;
        max-width: 320px;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }