/* roulang page: index */
:root {
      --primary: #F2410A;
      --primary-dark: #D12F00;
      --secondary-dark: #1A1C1E;
      --secondary-dark-soft: #2A2D30;
      --accent: #00E5F0;
      --white-warm: #F7F5F0;
      --white: #FFFFFF;
      --gray-border: #E8E5DF;
      --text-body: #1A1C1E;
      --text-muted: rgba(26,28,30,0.7);
      --text-footer: #9CA3AF;
      --success: #0FCF8E;
      --warning: #FFB800;
      --font-cn: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, sans-serif;
      --font-digits: "Oswald", "DIN Alternate", "Bebas Neue", var(--font-cn);
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 12px 32px rgba(0,0,0,0.08);
      --shadow-nav: 0 10px 30px rgba(0,0,0,0.15);
      --radius-sm: 12px;
      --radius-md: 16px;
      --radius-lg: 20px;
      --radius-btn: 100px;
      --nav-height: 80px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      background-color: var(--white-warm);
    }
    body {
      font-family: var(--font-cn);
      color: var(--text-body);
      line-height: 1.7;
      background: var(--white-warm);
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.25s ease, opacity 0.25s ease;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    button, input, textarea {
      font-family: inherit;
      outline: none;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 2rem;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 1.5rem;
      }
    }

    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 999;
      height: var(--nav-height);
      display: flex;
      align-items: center;
      background: transparent;
      transition: background 0.4s ease, backdrop-filter 0.4s ease, box-shadow 0.4s ease;
      border-bottom: 1px solid transparent;
    }
    #header.scrolled {
      background: rgba(26,28,30,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--primary);
      box-shadow: var(--shadow-nav);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: 1300px;
      margin: 0 auto;
      padding: 0 2rem;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 0.4rem;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--white-warm);
      letter-spacing: -0.02em;
      transition: color 0.3s;
    }
    .scrolled .logo {
      color: var(--white);
    }
    .logo-icon {
      width: 24px;
      height: 24px;
      background: var(--accent);
      border-radius: 4px;
      transform: rotate(45deg);
      display: inline-block;
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      list-style: none;
    }
    .nav-links a {
      color: rgba(255,255,255,0.8);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding-bottom: 4px;
    }
    .scrolled .nav-links a {
      color: rgba(255,255,255,0.9);
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%) scaleX(0);
      width: calc(100% + 4px);
      height: 2px;
      background: var(--primary);
      transition: transform 0.3s ease;
      border-radius: 2px;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      transform: translateX(-50%) scaleX(1);
    }
    .btn-nav {
      background: var(--primary);
      color: var(--white);
      padding: 0.6rem 1.8rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 0.9rem;
      letter-spacing: 0.02em;
      transition: background 0.3s, transform 0.25s;
      white-space: nowrap;
    }
    .btn-nav:hover {
      background: #E53E00;
      transform: translateY(-2px);
      color: white;
    }
    .burger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .burger span {
      width: 24px;
      height: 2px;
      background: var(--white-warm);
      transition: 0.3s;
      border-radius: 2px;
    }
    .scrolled .burger span {
      background: white;
    }
    @media (max-width: 1024px) {
      .nav-links {
        gap: 1.5rem;
      }
    }
    @media (max-width: 768px) {
      .nav-links, .btn-nav {
        display: none;
      }
      .burger {
        display: flex;
      }
      .mobile-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: var(--secondary-dark);
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 2rem;
        transform: translateX(100%);
        transition: transform 0.4s ease;
        z-index: 1000;
      }
      .mobile-menu.active {
        transform: translateX(0);
      }
      .mobile-menu a {
        font-size: 1.4rem;
        color: white;
        padding: 0.8rem 1rem;
        border-left: 3px solid transparent;
      }
      .mobile-menu a.active {
        color: var(--primary);
        border-left-color: var(--primary);
      }
      .mobile-close {
        position: absolute;
        top: 2rem;
        right: 2rem;
        background: none;
        border: none;
        font-size: 2rem;
        color: white;
      }
    }

    /* Hero */
    .hero {
      display: grid;
      grid-template-columns: 5fr 7fr;
      min-height: 100vh;
      background: var(--secondary-dark);
      overflow: hidden;
    }
    .hero-left {
      display: flex;
      flex-direction: column;
      justify-content: center;
      padding: 2rem 4rem 2rem max(3rem, 5vw);
      color: var(--white-warm);
    }
    .hero-tag {
      font-size: 0.8rem;
      letter-spacing: 0.15em;
      color: var(--accent);
      text-transform: uppercase;
      margin-bottom: 1.5rem;
    }
    .hero-left h1 {
      font-size: clamp(2.8rem, 5vw, 3.8rem);
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.03em;
      margin-bottom: 1.5rem;
      color: var(--white);
    }
    .highlight-orange {
      color: var(--primary);
      font-weight: 800;
      position: relative;
    }
    .hero-sub {
      font-size: 1.1rem;
      color: rgba(255,255,240,0.7);
      line-height: 1.6;
      margin-bottom: 2.5rem;
      max-width: 90%;
    }
    .hero-buttons {
      display: flex;
      gap: 1.2rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 0.9rem 2.4rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: all 0.25s ease;
      box-shadow: 0 8px 18px rgba(242,65,10,0.25);
    }
    .btn-primary:hover {
      background: #E53E00;
      transform: translateY(-4px);
      box-shadow: 0 12px 24px rgba(242,65,10,0.4);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid rgba(255,255,240,0.7);
      color: white;
      padding: 0.9rem 2.4rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.3s;
    }
    .btn-outline:hover {
      background: white;
      color: var(--secondary-dark);
    }
    .hero-right {
      position: relative;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .hero-img-collage {
      display: flex;
      gap: 12px;
      position: relative;
      width: 100%;
      height: 100%;
  }
  .dynamic-overlay {
      position: absolute;
      top: 0; left: 0; width: 100%; height: 100%;
      background: linear-gradient(135deg, rgba(26,28,30,0.5) 0%, rgba(242,65,10,0.2) 80%);
      display: flex;
      align-items: flex-end;
      padding: 2rem;
  }
  .geometric-lines {
      position: absolute;
      bottom: 3rem;
      left: 2rem;
      width: 120px;
      height: 120px;
      border: 3px solid rgba(0,229,240,0.5);
      border-radius: 0 20px 0 20px;
      transform: rotate(15deg);
  }
  @media (max-width: 768px) {
      .hero {
          grid-template-columns: 1fr;
      }
      .hero-left {
          padding: 6rem 1.5rem 2rem;
          order: 1;
      }
      .hero-right {
          height: 50vh;
          order: 2;
      }
  }

  /* 亮点网格 */
  .highlights {
      padding: 5rem 0;
  }
  .grid-3x2 {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 1.5rem;
  }
  .highlight-card {
      background: var(--white);
      border-radius: var(--radius-md);
      padding: 2rem;
      border: 1px solid var(--gray-border);
      transition: 0.25s ease;
      text-align: center;
  }
  .highlight-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-card-hover);
  }
  .high-icon {
      font-size: 2.5rem;
      color: var(--accent);
      margin-bottom: 1rem;
  }
  .big-number {
      font-family: var(--font-digits);
      font-size: 3.2rem;
      font-weight: 700;
      color: var(--primary);
  }
  @media (max-width: 768px) {
      .grid-3x2 { grid-template-columns: 1fr; }
  }

  /* 服务 */
  .services {
      padding: 5rem 0;
  }
  .masonry {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 1.8rem;
  }
  .service-card {
      background: white;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: 0.25s;
  }
  .service-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-card-hover); }
  .service-img {
      height: 140px;
      background-size: cover;
  }
  .service-body { padding: 1.5rem; }
  .link-arrow { color: var(--primary); font-weight: 600; transition: 0.3s; }
  .link-arrow:hover { text-decoration: underline; }
  @media (max-width: 1024px) { .masonry { grid-template-columns: 1fr 1fr; } }
  @media (max-width: 600px) { .masonry { grid-template-columns: 1fr; } }

  /* 对比 */
  .compare {
      padding: 5rem 0;
  }
  .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 0;
  }
  .plan-card {
      padding: 3rem;
      border-radius: var(--radius-lg);
  }
  .plan-standard { background: white; border: 1px solid var(--gray-border); }
  .plan-pro { background: var(--secondary-dark); color: white; position: relative; transform: scale(1.02); }
  .badge-recommend {
      position: absolute;
      top: -8px; right: 20px;
      background: var(--primary); color: white; padding: 0.3rem 1.8rem; border-radius: 20px;
  }
  .price { font-size: 2.5rem; font-weight: 700; color: var(--primary); }
  @media (max-width: 768px) {
      .compare-grid { grid-template-columns: 1fr; }
      .plan-pro { transform: none; }
  }

  /* 案例横向滚动 */
  .cases-scroll {
      display: flex;
      gap: 1.5rem;
      overflow-x: auto;
      scroll-snap-type: x mandatory;
      padding: 1rem 0 2rem;
  }
  .case-card {
      flex: 0 0 300px;
      scroll-snap-align: start;
      border-radius: var(--radius-lg);
      background: white;
      overflow: hidden;
  }
  .case-img { height: 180px; background-size: cover; transition: 0.3s; }
  .case-card:hover .case-img { transform: scale(1.05); }

  /* FAQ */
  .faq-section { max-width: 800px; margin: 5rem auto; }
  .faq-item { border-bottom: 1px solid var(--gray-border); padding: 1.5rem 0; cursor: pointer; }
  .faq-q { display: flex; justify-content: space-between; font-weight: 600; }

  /* CTA */
  .cta-full {
      background: var(--secondary-dark);
      display: grid;
      grid-template-columns: 1fr 1fr;
      padding: 4rem 3rem;
      color: white;
  }
  .form-dark input {
      background: #2A2D30; border: none; border-bottom: 1px solid #444; padding: 1rem; color: white;
      margin-bottom: 1rem;
  }
  @media (max-width: 768px) { .cta-full { grid-template-columns: 1fr; } }

  footer {
      background: var(--secondary-dark); color: var(--text-footer); padding: 2rem;
      display: grid; grid-template-columns: repeat(4,1fr); gap: 2rem;
  }