/* roulang page: index */
:root {
      --primary-deep: #0A0E27;
      --primary-soft: #1A1F3A;
      --accent-pink: #E8355A;
      --accent-orange: #FF6B35;
      --accent-gold: #FFD700;
      --gradient-main: linear-gradient(135deg, #E8355A 0%, #FF6B35 100%);
      --gradient-hero: linear-gradient(180deg, #0A0E27 0%, #1A1F3A 100%);
      --text-dark: #1E1E2E;
      --text-soft: #5B5B6B;
      --text-light: #B0B0C0;
      --bg-page: #FAFAFC;
      --bg-card: #FFFFFF;
      --bg-light: #F0F1F5;
      --border-light: #E8E8F0;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-md: 0 12px 32px rgba(0,0,0,0.08);
      --radius-card: 16px;
      --radius-btn: 50px;
      --radius-img: 24px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-dark);
      line-height: 1.7;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .top-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 99;
      display: flex;
      align-items: center;
      border-bottom: 1px solid rgba(0,0,0,0.02);
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo strong {
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: -0.5px;
    }
    .logo .brand-gradient {
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .logo .brand-dark {
      color: var(--text-dark);
    }
    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-dark);
      font-size: 0.95rem;
      position: relative;
      padding: 4px 0;
      white-space: nowrap;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 50%;
      transform: translateX(-50%);
      width: 0;
      height: 2px;
      background: var(--gradient-main);
      border-radius: 4px;
      transition: width 0.25s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 60%;
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--text-dark);
      cursor: pointer;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: fixed;
        top: 64px;
        left: 0;
        width: 100%;
        height: calc(100vh - 64px);
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(16px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 32px;
        font-size: 1.8rem;
        z-index: 100;
      }
      .nav-links.show {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
    }
    /* 板块间距 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }
    /* Hero */
    .hero {
      background: var(--gradient-hero);
      min-height: 90vh;
      display: flex;
      align-items: center;
      padding-top: 80px;
      color: white;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 55% 45%;
      gap: 40px;
      align-items: center;
    }
    .hero-left h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 24px;
      color: white;
    }
    .hero-left .highlight {
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero-sub {
      font-size: 1.1rem;
      color: #E0E0F0;
      max-width: 480px;
      margin-bottom: 32px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--gradient-main);
      color: white;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      transition: all 0.25s ease;
      display: inline-block;
      text-align: center;
      font-size: 1rem;
    }
    .btn-primary:hover {
      transform: scale(1.03);
      background: linear-gradient(135deg, #FF6B35 0%, #E8355A 100%);
      color: white;
    }
    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      transition: all 0.25s ease;
      display: inline-block;
      text-align: center;
      font-size: 1rem;
    }
    .btn-outline:hover {
      background: var(--gradient-main);
      border-color: transparent;
      transform: scale(1.03);
    }
    .hero-right .hero-img {
      border-radius: var(--radius-img);
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.3);
      transition: transform 0.3s;
    }
    .hero-right .hero-img:hover {
      transform: scale(1.02);
    }
    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-left h1 {
        font-size: 2.4rem;
      }
      .hero-sub {
        max-width: 100%;
      }
      .btn-group {
        justify-content: center;
      }
      .hero-right {
        order: -1;
        margin-bottom: 24px;
      }
    }
    /* 数据徽章 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      text-align: center;
    }
    .stat-item {
      padding: 24px 12px;
      border-right: 1px solid var(--border-light);
    }
    .stat-item:last-child {
      border-right: none;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 800;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      line-height: 1.2;
    }
    .stat-label {
      color: var(--text-soft);
      margin-top: 8px;
      font-weight: 500;
    }
    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: 1fr 1fr;
        border: none;
      }
      .stat-item {
        border-right: none;
        border-bottom: 1px solid var(--border-light);
        padding: 20px 8px;
      }
    }
    /* 核心优势卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .advantage-card {
      background: var(--bg-card);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all 0.25s ease;
      border: 1px solid transparent;
    }
    .advantage-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
      border-image: var(--gradient-main) 1;
      border-radius: var(--radius-card);
      outline: 2px solid transparent;
      outline-offset: -2px;
      background-clip: padding-box;
      position: relative;
    }
    .advantage-card:hover::before {
      content: '';
      position: absolute;
      top: 0; left: 0; right: 0; height: 4px;
      background: var(--gradient-main);
      border-radius: 16px 16px 0 0;
    }
    .advantage-icon {
      font-size: 2.2rem;
      color: #E8355A;
      margin-bottom: 16px;
    }
    .advantage-card h3 {
      font-weight: 700;
      margin-bottom: 12px;
    }
    @media (max-width: 768px) {
      .cards-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 案例瀑布流 */
    .waterfall {
      columns: 3;
      column-gap: 20px;
    }
    .case-card {
      break-inside: avoid;
      background: white;
      border-radius: 12px;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      margin-bottom: 20px;
      transition: all 0.2s;
    }
    .case-card:hover {
      box-shadow: var(--shadow-md);
    }
    .case-card img {
      width: 100%;
      display: block;
      transition: filter 0.3s;
    }
    .case-card:hover img {
      filter: saturate(1.2);
    }
    .case-info {
      padding: 20px;
    }
    .case-info h3 {
      font-weight: 700;
      margin-bottom: 6px;
    }
    .case-date {
      color: var(--text-soft);
      font-size: 0.85rem;
    }
    @media (max-width: 768px) {
      .waterfall {
        columns: 2;
      }
    }
    @media (max-width: 520px) {
      .waterfall {
        columns: 1;
      }
    }
    /* 对比表 */
    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
      align-items: start;
    }
    .compare-col {
      background: #F5F5F8;
      border-radius: 20px;
      padding: 32px;
    }
    .compare-col.highlight {
      background: white;
      border-left: 6px solid;
      border-image: var(--gradient-main) 1;
      box-shadow: var(--shadow-sm);
    }
    .compare-col h3 {
      font-weight: 700;
      margin-bottom: 24px;
    }
    .compare-list {
      list-style: none;
    }
    .compare-list li {
      margin-bottom: 14px;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .text-muted {
      color: var(--text-soft);
    }
    @media (max-width: 768px) {
      .compare-grid {
        grid-template-columns: 1fr;
      }
    }
    /* FAQ */
    .accordion-item {
      border-bottom: 1px solid var(--border-light);
      padding: 16px 0;
    }
    .accordion-question {
      font-weight: 700;
      font-size: 1.1rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text-dark);
    }
    .accordion-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-soft);
    }
    .accordion-answer.open {
      max-height: 200px;
      margin-top: 12px;
    }
    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #0A0E27, #2A1E3A);
      color: white;
      text-align: center;
    }
    .cta-form {
      display: flex;
      gap: 16px;
      justify-content: center;
      flex-wrap: wrap;
      margin-top: 32px;
    }
    .cta-form input {
      padding: 14px 20px;
      border-radius: 8px;
      border: none;
      background: white;
      min-width: 220px;
    }
    @media (max-width: 768px) {
      .cta-form {
        flex-direction: column;
        align-items: center;
      }
    }
    /* 页脚 */
    .footer {
      background: #0A0E27;
      color: #B0B0C0;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }