/* roulang page: index */
:root {
      --primary: #0A0E27;
      --accent: #00F0FF;
      --highlight: #FF3CAC;
      --neutral-light: #F5F7FA;
      --neutral-dark: #1A1F3A;
      --text-muted: #8E94A4;
      --text-main: #E8EAEF;
      --card-radius: 12px;
      --btn-radius: 8px;
      --input-radius: 6px;
      --shadow-card: 0 4px 20px rgba(0,240,255,0.08);
      --shadow-hover: 0 8px 30px rgba(0,240,255,0.2);
      --transition: all 0.25s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", system-ui, sans-serif;
      --gap-section: 100px;
      --gap-card: 28px;
      --gap-grid: 24px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--primary);
      color: var(--text-main);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 2rem;
    }

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

    a:hover {
      color: #33F5FF;
      text-shadow: 0 0 8px rgba(0,240,255,0.4);
    }

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

    h1, h2, h3 {
      font-weight: 700;
      letter-spacing: -0.3px;
    }

    h1 {
      font-size: 48px;
      line-height: 1.2;
    }

    h2 {
      font-size: 36px;
      line-height: 1.3;
      margin-bottom: 1.5rem;
    }

    h3 {
      font-size: 22px;
      line-height: 1.4;
    }

    p {
      margin-bottom: 1.5em;
      color: var(--text-muted);
      font-weight: 400;
    }

    button, .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0.85rem 2.2rem;
      border-radius: var(--btn-radius);
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      border: none;
      transition: var(--transition);
      text-decoration: none;
      background: transparent;
      color: var(--text-main);
    }

    .btn-primary {
      background: var(--accent);
      color: #0A0E27;
      box-shadow: 0 0 12px rgba(0,240,255,0.15);
    }

    .btn-primary:hover {
      background: #33F5FF;
      box-shadow: 0 0 20px rgba(0,240,255,0.6);
      color: #0A0E27;
    }

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

    .btn-outline:hover {
      background: rgba(0,240,255,0.08);
      border-color: #33F5FF;
    }

    .btn-highlight {
      background: var(--highlight);
      color: white;
      box-shadow: 0 0 16px rgba(255,60,172,0.3);
    }

    .btn-highlight:hover {
      background: #ff5cbf;
      box-shadow: 0 0 28px rgba(255,60,172,0.6);
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10, 14, 39, 0.8);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,240,255,0.15);
      transition: var(--transition);
    }

    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 1rem 2rem;
      max-width: 1280px;
      margin: 0 auto;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      color: white;
      letter-spacing: 1px;
      text-decoration: none;
    }
    .logo span {
      color: var(--accent);
    }

    .nav-links {
      display: flex;
      gap: 2.5rem;
      align-items: center;
    }

    .nav-links a {
      color: var(--text-muted);
      font-weight: 500;
      position: relative;
      padding-bottom: 4px;
    }

    .nav-links a.active,
    .nav-links a:hover {
      color: var(--accent);
    }

    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent);
      box-shadow: 0 0 8px var(--accent);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 4px;
    }
    .hamburger span {
      width: 25px;
      height: 2px;
      background: var(--accent);
      transition: var(--transition);
    }

    /* 首屏 Hero */
    .hero {
      padding: 140px 0 80px;
      background: radial-gradient(circle at 30% 40%, #0f1535, #0A0E27 80%);
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-blend-mode: overlay;
      position: relative;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: repeating-linear-gradient(0deg, rgba(0,240,255,0.03) 0px, rgba(0,240,255,0.03) 2px, transparent 2px, transparent 8px);
      pointer-events: none;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
      position: relative;
    }
    .hero-left h1 {
      color: white;
      margin-bottom: 1.2rem;
      text-shadow: 0 0 20px rgba(0,240,255,0.3);
    }
    .hero-sub {
      font-size: 1.25rem;
      color: var(--text-muted);
      margin-bottom: 2.5rem;
    }
    .hero-visual {
      background: rgba(26,31,58,0.7);
      border-radius: 24px;
      overflow: hidden;
      border: 1px solid rgba(0,240,255,0.25);
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      animation: float 4s ease-in-out infinite;
      backdrop-filter: blur(4px);
    }
    @keyframes float {
      0% { transform: translateY(0); }
      50% { transform: translateY(-10px); }
      100% { transform: translateY(0); }
    }

    /* 亮点网格 */
    .features {
      padding: var(--gap-section) 0;
      background: #0b102a;
    }
    .features-grid {
      display: grid;
      grid-template-columns: 2fr 1fr;
      gap: var(--gap-grid);
    }
    .feature-card {
      background: var(--neutral-dark);
      border-radius: var(--card-radius);
      padding: var(--gap-card);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border: 1px solid transparent;
    }
    .feature-card.large {
      background: #232844;
    }
    .feature-card:hover {
      box-shadow: var(--shadow-hover);
      border-color: var(--accent);
      transform: translateY(-4px);
    }
    .feature-icon {
      font-size: 2.2rem;
      color: var(--accent);
      margin-bottom: 1rem;
    }
    .feature-card h3 {
      color: white;
      margin-bottom: 0.8rem;
    }
    .text-link {
      color: var(--accent);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    /* 案例瀑布 */
    .cases {
      padding: var(--gap-section) 0;
    }
    .waterfall {
      columns: 3 280px;
      column-gap: var(--gap-grid);
    }
    .case-item {
      break-inside: avoid;
      background: var(--neutral-dark);
      border-radius: var(--card-radius);
      overflow: hidden;
      margin-bottom: var(--gap-grid);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border: 1px solid transparent;
    }
    .case-item:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: var(--accent);
    }
    .case-img {
      height: 180px;
      background-size: cover;
      background-position: center;
    }
    .case-content {
      padding: 1.5rem;
    }
    .tag {
      display: inline-block;
      background: var(--highlight);
      color: white;
      font-size: 0.75rem;
      padding: 0.25rem 0.8rem;
      border-radius: 20px;
      margin-right: 0.5rem;
      font-weight: 600;
    }

    /* 方案对比 */
    .compare {
      padding: var(--gap-section) 0;
      background: #0b102a;
    }
    .compare-panels {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2rem;
      align-items: start;
    }
    .panel {
      background: var(--neutral-dark);
      border-radius: var(--card-radius);
      padding: 2rem;
      box-shadow: var(--shadow-card);
    }
    .panel.right {
      border: 1px solid var(--accent);
      background: #151d3d;
    }
    .feature-list {
      list-style: none;
      margin-top: 1.5rem;
    }
    .feature-list li {
      margin-bottom: 0.8rem;
      display: flex;
      align-items: center;
      gap: 0.6rem;
    }
    .check {
      color: var(--accent);
      font-weight: bold;
    }
    .cross {
      color: var(--highlight);
    }

    /* FAQ */
    .faq {
      padding: var(--gap-section) 0;
    }
    .accordion-item {
      background: var(--neutral-dark);
      margin-bottom: 1rem;
      border-radius: var(--card-radius);
      overflow: hidden;
      border: 1px solid transparent;
      transition: var(--transition);
    }
    .accordion-item.active {
      border-color: var(--accent);
      background: #252c4a;
    }
    .accordion-header {
      padding: 1.5rem;
      font-weight: 700;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: white;
    }
    .accordion-icon {
      font-size: 1.8rem;
      color: var(--accent);
      transition: var(--transition);
    }
    .accordion-body {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 1.5rem;
      color: var(--text-muted);
    }
    .accordion-item.active .accordion-body {
      max-height: 200px;
      padding-bottom: 1.5rem;
    }

    /* CTA 横幅 */
    .cta-banner {
      background: linear-gradient(135deg, #11163b, #0A0E27);
      padding: 4rem 0;
      text-align: center;
      border-top: 1px solid var(--accent);
      border-bottom: 1px solid var(--accent);
    }

    /* 页脚 */
    .site-footer {
      background: #080b1f;
      padding: 3rem 0 1.5rem;
      font-size: 0.9rem;
      color: var(--text-muted);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }

    @media (max-width: 1024px) {
      .container { padding: 0 1.5rem; }
      .hero-grid { grid-template-columns: 1fr; }
      .features-grid { grid-template-columns: 1fr; }
      .compare-panels { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      h1 { font-size: 36px; }
      h2 { font-size: 28px; }
      .nav-links { display: none; position: fixed; top: 70px; left: 0; width: 100%; background: #0A0E27; flex-direction: column; padding: 2rem; gap: 1.5rem; }
      .nav-links.open { display: flex; }
      .hamburger { display: flex; }
      .waterfall { columns: 1; }
      .hero { padding: 120px 0 60px; }
    }