/* roulang page: index */
:root {
      --primary: #00C9A7;
      --secondary: #1A1E2B;
      --accent: #FF6B35;
      --bg: #F5F1EC;
      --card-bg: #FFFFFF;
      --text-main: #1A1E2B;
      --text-body: #3A3F4A;
      --text-weak: #7A7F8A;
      --border-light: #E0E0E0;
      --radius: 12px;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --max-width: 1280px;
      --nav-height: 72px;
      --transition: all 0.25s ease;
    }

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

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

    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }

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

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

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

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    #home {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(26,30,43,0.85);
      backdrop-filter: blur(12px);
      transition: background 0.3s;
      height: var(--nav-height);
      display: flex;
      align-items: center;
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }

    #home.scrolled {
      background: var(--secondary);
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      display: flex;
      align-items: baseline;
      gap: 8px;
      color: white;
      font-weight: 800;
      font-size: 1.6rem;
      letter-spacing: -0.3px;
      line-height: 1;
    }

    .logo span {
      font-size: 0.8rem;
      font-weight: 400;
      opacity: 0.8;
      letter-spacing: 1px;
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }

    .nav-links a {
      color: white;
      font-size: 0.95rem;
      font-weight: 500;
      padding: 6px 0;
      border-bottom: 3px solid transparent;
      transition: var(--transition);
      white-space: nowrap;
    }

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

    .burger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
      z-index: 1001;
    }

    .burger span {
      display: block;
      width: 28px;
      height: 2px;
      background: white;
      transition: 0.3s;
    }

    @media (max-width: 1024px) {
      .nav-links {
        gap: 20px;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 320px;
        height: 100vh;
        background: var(--secondary);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 36px;
        transition: right 0.35s ease;
        box-shadow: -10px 0 30px rgba(0,0,0,0.3);
      }
      .nav-links.open {
        right: 0;
      }
      .burger {
        display: flex;
      }
    }

    /* Hero 双栏 */
    #hero {
      padding: calc(var(--nav-height) + 40px) 0 60px;
      background-color: var(--secondary);
      color: white;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }

    .hero-left h1 {
      font-size: 3rem;
      font-weight: 800;
      line-height: 1.2;
      letter-spacing: -0.5px;
      margin-bottom: 20px;
    }

    .hero-left .sub {
      font-size: 1.15rem;
      opacity: 0.85;
      margin-bottom: 36px;
      max-width: 90%;
    }

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

    .btn-primary {
      background: var(--accent);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      transition: var(--transition);
      display: inline-block;
    }

    .btn-primary:hover {
      background: var(--secondary);
      box-shadow: 0 8px 18px rgba(0,0,0,0.2);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 14px 32px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      transition: var(--transition);
    }

    .btn-outline:hover {
      background: var(--primary);
      color: var(--secondary);
    }

    .hero-right {
      position: relative;
      border-radius: var(--radius);
      overflow: hidden;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 380px;
    }

    .hero-right::after {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(0,201,167,0.25);
      mix-blend-mode: overlay;
    }

    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .hero-left h1 {
        font-size: 2.2rem;
      }
      .hero-right {
        min-height: 260px;
      }
    }

    /* 亮点网格 */
    #highlights {
      padding: 80px 0;
    }

    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 48px;
      text-align: center;
    }

    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .highlight-card {
      background: var(--card-bg);
      border-radius: var(--radius);
      padding: 32px 24px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border-top: 4px solid transparent;
    }

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

    .icon-placeholder {
      width: 36px;
      height: 36px;
      background: var(--primary);
      border-radius: 8px;
      margin-bottom: 20px;
    }

    .highlight-card h3 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 12px;
      color: var(--text-main);
    }

    @media (max-width: 1024px) {
      .highlights-grid {
        grid-template-columns: repeat(2,1fr);
      }
    }

    @media (max-width: 640px) {
      .highlights-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 案例瀑布流 */
    #cases {
      padding: 80px 0;
    }

    .masonry {
      columns: 3;
      column-gap: 24px;
    }

    .case-card {
      break-inside: avoid;
      background: var(--card-bg);
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      margin-bottom: 24px;
      overflow: hidden;
      transition: var(--transition);
    }

    .case-card:hover {
      box-shadow: var(--shadow-hover);
    }

    .case-img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }

    .case-content {
      padding: 20px;
    }

    .tag {
      background: var(--accent);
      color: white;
      font-size: 0.75rem;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 10px;
      font-weight: 600;
    }

    .case-title {
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--text-main);
    }

    @media (max-width: 1024px) {
      .masonry {
        columns: 2;
      }
    }

    @media (max-width: 640px) {
      .masonry {
        columns: 1;
      }
    }

    /* 方案对比 */
    #solutions {
      padding: 80px 0;
    }

    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }

    .compare-card {
      background: white;
      border-radius: var(--radius);
      padding: 36px 28px;
      box-shadow: var(--shadow-sm);
    }

    .compare-card.traditional {
      opacity: 0.8;
      background: #f9f9f9;
    }

    .compare-card.recommend {
      border: 2px solid var(--primary);
      position: relative;
    }

    .badge {
      position: absolute;
      top: -12px;
      right: 24px;
      background: var(--accent);
      color: white;
      padding: 4px 16px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 700;
    }

    .compare-row {
      display: flex;
      justify-content: space-between;
      padding: 14px 0;
      border-bottom: 1px solid #eee;
    }

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

    /* FAQ */
    #faq {
      padding: 80px 0;
    }

    .accordion {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      background: white;
      border-radius: var(--radius);
      margin-bottom: 16px;
      box-shadow: var(--shadow-sm);
      overflow: hidden;
    }

    .faq-question {
      padding: 20px 28px;
      font-weight: 700;
      font-size: 1.1rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      background: white;
      border: none;
      width: 100%;
      text-align: left;
      color: var(--text-main);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: rgba(0,201,167,0.03);
      padding: 0 28px;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 20px 28px;
      border-left: 4px solid var(--primary);
    }

    /* CTA */
    #contact {
      background: var(--secondary);
      color: white;
      padding: 80px 0;
    }

    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
    }

    .contact-form input,
    .contact-form textarea {
      width: 100%;
      padding: 14px;
      margin-bottom: 20px;
      border-radius: 8px;
      border: none;
      background: rgba(255,255,255,0.1);
      color: white;
      font-size: 1rem;
    }

    .contact-form input::placeholder,
    .contact-form textarea::placeholder {
      color: #ccc;
    }

    .btn-submit {
      background: var(--accent);
      color: white;
      border: none;
      padding: 14px 28px;
      border-radius: 30px;
      font-weight: 700;
      cursor: pointer;
    }

    .contact-info p {
      margin-bottom: 16px;
      opacity: 0.9;
    }

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

    /* 页脚 */
    #footer {
      background: #0f1118;
      color: #aaa;
      padding: 48px 0 24px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr;
      gap: 32px;
      margin-bottom: 32px;
    }

    .footer-brand {
      font-size: 1.4rem;
      font-weight: 800;
      color: white;
    }

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