/* roulang page: index */
:root {
      --primary-purple: #7B2FF7;
      --accent-rose: #E01E5A;
      --bg-deep: #0B0C10;
      --card-surface: #15161E;
      --text-primary: #F0F0F5;
      --text-secondary: #A0A3B1;
      --highlight-cyan: #00F0FF;
      --gradient-main: linear-gradient(135deg, #7B2FF7 0%, #E01E5A 100%);
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --shadow-hover: 0 12px 40px rgba(123, 47, 247, 0.25);
      --border-card: 1px solid rgba(123, 47, 247, 0.15);
      --border-hover: 1px solid rgba(224, 30, 90, 0.5);
      --radius-lg: 16px;
      --radius-full: 50px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-number: 'DIN Alternate', 'PingFang SC', sans-serif;
      --transition-smooth: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    }

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

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-deep);
      color: var(--text-primary);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

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

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* 导航 */
    #main-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      z-index: 100;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 32px;
      backdrop-filter: blur(0px);
      background: transparent;
      transition: var(--transition-smooth);
    }

    #main-nav.scrolled {
      background: rgba(11, 12, 16, 0.88);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 24px rgba(0,0,0,0.5);
      border-bottom: 1px solid rgba(123,47,247,0.2);
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 1px;
    }

    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
      list-style: none;
    }

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-secondary);
      padding: 0.5rem 0;
      position: relative;
    }

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

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

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

    .mobile-nav {
      display: none;
    }

    /* Hero */
    #hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      background: url('/assets/images/backpic/hero-bg.webp') center/cover no-repeat;
      background-attachment: fixed;
      text-align: center;
      padding: 0 24px;
    }

    .hero-overlay {
      position: absolute;
      inset: 0;
      background: rgba(11, 12, 16, 0.7);
      z-index: 1;
    }

    .hero-radial {
      position: absolute;
      bottom: 0;
      right: 0;
      width: 70%;
      height: 70%;
      background: radial-gradient(circle at 80% 80%, rgba(123,47,247,0.3), transparent 70%);
      z-index: 1;
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 900px;
    }

    .hero-content h1 {
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.2;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 1.5rem;
      letter-spacing: 0.5px;
    }

    .hero-sub {
      font-size: 1.1rem;
      color: var(--text-secondary);
      margin-bottom: 2.5rem;
    }

    .btn-group {
      display: flex;
      gap: 1rem;
      justify-content: center;
      flex-wrap: wrap;
    }

    .btn {
      display: inline-block;
      padding: 14px 36px;
      border-radius: var(--radius-full);
      font-weight: 600;
      font-size: 1rem;
      transition: var(--transition-smooth);
      cursor: pointer;
      border: none;
      text-align: center;
    }

    .btn-primary {
      background: var(--gradient-main);
      color: white;
      box-shadow: 0 4px 20px rgba(123,47,247,0.3);
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, #E01E5A 0%, #7B2FF7 100%);
      box-shadow: 0 0 24px rgba(123,47,247,0.6);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid transparent;
      background-image: var(--gradient-main);
      background-origin: border-box;
      background-clip: padding-box, border-box;
      color: white;
      position: relative;
      border: 2px solid #7B2FF7;
    }

    .btn-outline:hover {
      background: rgba(123,47,247,0.1);
      border-color: #E01E5A;
    }

    .scroll-indicator {
      position: absolute;
      bottom: 30px;
      left: 50%;
      transform: translateX(-50%);
      z-index: 2;
      animation: bounce 2s infinite;
      color: var(--text-secondary);
      font-size: 2rem;
    }

    @keyframes bounce {
      0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); }
      40% { transform: translateX(-50%) translateY(-10px); }
      60% { transform: translateX(-50%) translateY(-5px); }
    }

    /* 通用区块 */
    section {
      padding: 100px 0;
    }

    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      margin-bottom: 1rem;
      text-align: center;
    }

    .section-desc {
      color: var(--text-secondary);
      text-align: center;
      max-width: 700px;
      margin: 0 auto 3rem;
      font-size: 1.1rem;
    }

    /* 卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .card {
      background: var(--card-surface);
      border-radius: var(--radius-lg);
      padding: 2rem;
      border: var(--border-card);
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }

    .card:hover {
      border: var(--border-hover);
      box-shadow: var(--shadow-hover);
      transform: translateY(-6px);
    }

    .icon-placeholder {
      width: 56px;
      height: 56px;
      background: rgba(123,47,247,0.15);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 1.5rem;
      color: var(--primary-purple);
      font-size: 1.8rem;
    }

    .card h3 {
      font-size: 1.4rem;
      margin-bottom: 0.75rem;
    }

    .card p {
      color: var(--text-secondary);
      line-height: 1.6;
    }

    /* 数据区 */
    .data-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }

    .data-badge {
      background: var(--card-surface);
      border-radius: var(--radius-lg);
      padding: 2.5rem 1rem;
      text-align: center;
      border: var(--border-card);
    }

    .data-number {
      font-family: var(--font-number);
      font-size: 3.2rem;
      font-weight: 700;
      color: var(--highlight-cyan);
      text-shadow: 0 0 14px rgba(0,240,255,0.3);
      letter-spacing: 1px;
    }

    .data-label {
      color: var(--text-secondary);
      margin-top: 0.5rem;
    }

    /* 案例横向卡 */
    .case-row {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }

    .case-card {
      display: flex;
      background: var(--card-surface);
      border-radius: var(--radius-lg);
      overflow: hidden;
      border: var(--border-card);
      transition: var(--transition-smooth);
    }

    .case-card:hover {
      border-color: rgba(224,30,90,0.5);
      box-shadow: var(--shadow-hover);
    }

    .case-img {
      width: 38%;
      min-height: 240px;
      object-fit: cover;
      transition: transform 0.4s ease;
    }

    .case-card:hover .case-img {
      transform: scale(1.04);
    }

    .case-info {
      padding: 2rem;
      display: flex;
      flex-direction: column;
      justify-content: center;
      border-left: 2px solid transparent;
      transition: 0.3s;
    }

    .case-card:hover .case-info {
      border-left: 4px solid var(--accent-rose);
    }

    .tag {
      display: inline-block;
      background: var(--gradient-main);
      color: white;
      padding: 0.25rem 1rem;
      border-radius: 20px;
      font-size: 0.8rem;
      margin-bottom: 0.8rem;
      width: fit-content;
    }

    /* 业务方案图文卡 */
    .solution-img {
      width: 100%;
      height: 200px;
      object-fit: cover;
      border-radius: 12px 12px 0 0;
    }

    .card.link-card {
      padding: 0;
    }
    .card-body {
      padding: 1.5rem;
    }
    .text-link {
      color: var(--primary-purple);
      font-weight: 600;
      display: inline-block;
      margin-top: 0.5rem;
      background: linear-gradient(to right, #7B2FF7, #E01E5A) left bottom no-repeat;
      background-size: 0% 2px;
      transition: 0.3s;
    }
    .card:hover .text-link {
      background-size: 100% 2px;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .faq-item {
      background: var(--card-surface);
      border-radius: var(--radius-lg);
      border: var(--border-card);
      transition: 0.2s;
    }
    .faq-item[open] {
      background: #1E1F28;
      border-left: 4px solid #7B2FF7;
    }
    summary {
      padding: 1.2rem 1.8rem;
      font-weight: 600;
      cursor: pointer;
      list-style: none;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    summary::-webkit-details-marker { display: none; }
    .faq-answer {
      padding: 0 1.8rem 1.5rem;
      color: var(--text-secondary);
    }

    /* CTA */
    .cta-band {
      background: var(--gradient-main);
      text-align: center;
      padding: 5rem 24px;
      border-radius: 32px;
      margin: 0 24px;
    }
    .btn-white {
      background: white;
      color: #7B2FF7;
      font-weight: 700;
    }

    /* 页脚 */
    footer {
      background: #0B0C10;
      padding: 3rem 24px 1.5rem;
      border-top: 1px solid rgba(255,255,255,0.08);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 2rem;
    }
    .footer-logo {
      font-size: 1.6rem;
      font-weight: 700;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2,1fr); }
      .data-grid { grid-template-columns: repeat(2,1fr); }
      .case-card { flex-direction: column; }
      .case-img { width: 100%; height: 200px; }
    }

    @media (max-width: 767px) {
      .nav-links { display: none; }
      .mobile-nav {
        display: flex;
        position: fixed;
        bottom: 16px;
        left: 16px;
        right: 16px;
        background: rgba(21,22,30,0.92);
        backdrop-filter: blur(20px);
        border-radius: 40px;
        padding: 0.8rem 1.2rem;
        justify-content: space-around;
        z-index: 100;
        box-shadow: 0 8px 30px rgba(0,0,0,0.6);
        border: 1px solid rgba(123,47,247,0.2);
      }
      .mobile-nav a {
        font-size: 0.75rem;
        color: var(--text-secondary);
        display: flex;
        flex-direction: column;
        align-items: center;
        gap: 4px;
      }
      .grid-3, .data-grid, .footer-grid { grid-template-columns: 1fr; }
      section { padding: 70px 0; }
      .hero-content h1 { font-size: 2.2rem; }
      .data-number { font-size: 2.6rem; }
      .case-img { height: 180px; }
      .cta-band { margin: 0 12px; }
    }