/* roulang page: index */
:root {
      --primary: #7B2FBE;
      --secondary: #00E5A0;
      --bg-deep: #0D0D1A;
      --bg-card: #1A1A2E;
      --text-light: #F0F0FF;
      --text-muted: #8E8EA0;
      --border-subtle: rgba(255, 255, 255, 0.06);
      --gradient-main: linear-gradient(135deg, #7B2FBE 0%, #00E5A0 100%);
      --shadow-glow: 0 8px 32px rgba(123, 47, 190, 0.25);
      --radius-card: 16px;
      --radius-btn: 40px;
      --radius-tag: 20px;
      --max-width: 1280px;
      --font-sans: 'Noto Sans SC', sans-serif;
      --font-mono: 'Inter', sans-serif;
      --transition: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
    }

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

    html {
      scroll-behavior: smooth;
      background-color: var(--bg-deep);
    }

    body {
      font-family: var(--font-sans);
      background: var(--bg-deep);
      color: var(--text-light);
      line-height: 1.7;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }

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

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

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

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

    h1, h2, h3 {
      font-weight: 700;
      line-height: 1.2;
    }

    h1 {
      font-size: 3.5rem;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: 2.5rem;
      margin-bottom: 1rem;
    }

    h3 {
      font-size: 1.4rem;
      font-weight: 600;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(13, 13, 26, 0.8);
      backdrop-filter: blur(16px);
      transition: background 0.3s, box-shadow 0.3s;
      border-bottom: 1px solid transparent;
    }

    .header.scrolled {
      background: rgba(13, 13, 26, 0.96);
      box-shadow: 0 1px 0 rgba(123, 47, 190, 0.3);
    }

    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 32px;
      height: 72px;
      max-width: 1400px;
      margin: 0 auto;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--text-light);
    }

    .logo-icon {
      font-size: 2rem;
      color: var(--secondary);
      filter: drop-shadow(0 0 6px var(--secondary));
    }

    .nav-links {
      display: flex;
      gap: 36px;
      font-weight: 500;
      color: #d1d1e0;
    }

    .nav-links a {
      position: relative;
      padding: 8px 0;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--gradient-main);
      transition: 0.25s ease;
    }

    .nav-links a:hover {
      color: white;
    }

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

    .btn-primary {
      background: var(--gradient-main);
      color: white;
      border: none;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      cursor: pointer;
      transition: 0.3s;
      background-size: 100% 100%;
      box-shadow: 0 4px 14px rgba(123, 47, 190, 0.4);
      border: 1px solid transparent;
    }

    .btn-primary:hover {
      transform: scale(1.04);
      box-shadow: 0 8px 22px rgba(0, 229, 160, 0.3);
      background-size: 110% 110%;
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--secondary);
      color: var(--secondary);
      padding: 10px 26px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.3s;
    }

    .btn-outline:hover {
      background: rgba(0, 229, 160, 0.08);
      border-color: #fff;
      color: #fff;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }

    .hamburger span {
      width: 26px;
      height: 2px;
      background: var(--text-light);
      transition: 0.3s;
    }

    /* Hero */
    .hero {
      padding: 140px 0 80px;
      display: flex;
      align-items: center;
      gap: 48px;
    }

    .hero-left {
      flex: 1.2;
    }

    .hero-right {
      flex: 1;
      position: relative;
    }

    .hero-img {
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 0 20px rgba(123, 47, 190, 0.35);
      border: 1px solid rgba(255, 255, 255, 0.12);
    }

    .gradient-text {
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .hero-sub {
      color: var(--text-muted);
      font-size: 1.2rem;
      margin: 24px 0 36px;
    }

    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    /* 亮点网格 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 20px;
    }

    .stat-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      border: 1px solid var(--border-subtle);
      transition: var(--transition);
      position: relative;
    }

    .stat-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 20%;
      width: 60%;
      height: 2px;
      background: var(--primary);
    }

    .stat-number {
      font-family: var(--font-mono);
      font-weight: 800;
      font-size: 2.8rem;
      color: var(--secondary);
    }

    .stat-label {
      color: var(--text-muted);
      margin-top: 8px;
    }

    /* 服务卡片瀑布流 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      margin-top: 40px;
    }

    .service-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-subtle);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
    }

    .service-card:nth-child(2) {
      margin-top: 30px;
    }

    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-glow);
      border-color: rgba(123, 47, 190, 0.4);
    }

    .service-img {
      height: 200px;
      object-fit: cover;
    }

    .service-content {
      padding: 24px;
    }

    .tags {
      display: flex;
      gap: 10px;
      margin: 16px 0 8px;
      flex-wrap: wrap;
    }

    .tag {
      background: rgba(0, 229, 160, 0.12);
      color: var(--secondary);
      padding: 4px 14px;
      border-radius: var(--radius-tag);
      font-size: 0.8rem;
      font-weight: 600;
    }

    /* 横向滚动案例 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding: 20px 0 32px;
      scrollbar-width: thin;
      scrollbar-color: var(--primary) var(--bg-card);
    }

    .case-card {
      min-width: 320px;
      background: var(--bg-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-subtle);
    }

    .case-img {
      height: 200px;
      object-fit: cover;
    }

    .case-info {
      padding: 20px;
    }

    /* 对比表 */
    .compare-container {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 0;
      background: var(--bg-card);
      border-radius: var(--radius-card);
      overflow: hidden;
    }

    .compare-col {
      padding: 40px;
    }

    .compare-col:first-child {
      border-right: 1px solid rgba(255,255,255,0.08);
    }

    .compare-item {
      display: flex;
      align-items: center;
      gap: 12px;
      margin: 20px 0;
    }

    /* FAQ */
    .faq-item {
      background: var(--bg-card);
      border-radius: 12px;
      margin-bottom: 14px;
      border: 1px solid var(--border-subtle);
      transition: 0.25s;
    }

    .faq-question {
      padding: 20px 28px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }

    .faq-answer {
      padding: 0 28px 20px;
      color: var(--text-muted);
      display: none;
    }

    .faq-item.active {
      border-color: var(--primary);
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    /* CTA */
    .cta-block {
      background: var(--gradient-main);
      border-radius: 32px;
      padding: 70px 48px;
      text-align: center;
      margin: 80px 0;
    }

    .cta-form {
      display: flex;
      gap: 16px;
      margin-top: 36px;
      flex-wrap: wrap;
      justify-content: center;
    }

    .cta-form input {
      padding: 14px 20px;
      border-radius: 40px;
      border: none;
      background: rgba(255,255,255,0.15);
      color: white;
      min-width: 200px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.5fr 1.2fr;
      gap: 40px;
      padding: 60px 0;
    }

    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2,1fr); }
      .service-card:nth-child(2) { margin-top: 0; }
    }

    @media (max-width: 768px) {
      .nav-links, .nav .btn-primary { display: none; }
      .hamburger { display: flex; }
      .hero { flex-direction: column; }
      .highlights-grid { grid-template-columns: 1fr 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .compare-container { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 520px) {
      h1 { font-size: 2.4rem; }
      .highlights-grid { grid-template-columns: 1fr; }
    }