/* roulang page: index */
:root {
      --deep-blue: #0B1A2E;
      --dark-gradient: #162D50;
      --silver: #E8EDF2;
      --champagne: #C9A96E;
      --champagne-dark: #B8924F;
      --aurora: #5EEAD4;
      --bg-light: #F5F7FA;
      --white: #FFFFFF;
      --text-primary: #334155;
      --text-secondary: #64748B;
      --border-light: #E2E8F0;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 6px 16px rgba(0,0,0,0.04);
      --shadow-hover: 0 4px 12px rgba(0,0,0,0.08), 0 12px 28px rgba(0,0,0,0.06);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --transition: 0.25s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      margin: 0;
      background-color: var(--bg-light);
      color: var(--text-primary);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      margin: 0;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }
    /* 导航卡片化面板 */
    .nav-panel {
      position: fixed;
      top: 16px;
      left: 50%;
      transform: translateX(-50%);
      width: calc(100% - 40px);
      max-width: 1200px;
      background: rgba(255,255,255,0.88);
      backdrop-filter: blur(12px);
      border-radius: 16px;
      box-shadow: 0 10px 30px rgba(0,0,0,0.05);
      padding: 12px 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      z-index: 100;
      border: 1px solid rgba(255,255,255,0.4);
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      letter-spacing: 1px;
      color: var(--deep-blue);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i {
      color: var(--champagne);
      font-size: 26px;
    }
    .nav-categories {
      display: flex;
      gap: 8px;
      align-items: center;
    }
    .nav-cat-item {
      background: transparent;
      border-radius: 10px;
      padding: 8px 14px;
      font-size: 15px;
      font-weight: 500;
      color: var(--text-primary);
      display: flex;
      align-items: center;
      gap: 6px;
      transition: background var(--transition), color var(--transition);
    }
    .nav-cat-item i {
      font-size: 16px;
      color: var(--champagne);
    }
    .nav-cat-item:hover {
      background: rgba(201,169,110,0.1);
      color: var(--deep-blue);
    }
    .cta-main-btn {
      background: var(--champagne);
      color: var(--deep-blue);
      font-weight: 600;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-size: 15px;
      transition: background var(--transition), transform var(--transition);
      white-space: nowrap;
      border: none;
      cursor: pointer;
      display: inline-block;
    }
    .cta-main-btn:hover {
      background: var(--champagne-dark);
      transform: translateY(-1px);
      color: var(--deep-blue);
    }
    /* 移动端导航 */
    .mobile-nav {
      display: none;
    }
    @media (max-width: 840px) {
      .nav-panel {
        top: auto;
        bottom: 0;
        left: 0;
        transform: none;
        width: 100%;
        border-radius: 20px 20px 0 0;
        padding: 8px 12px;
        background: rgba(255,255,255,0.95);
        backdrop-filter: blur(16px);
      }
      .nav-panel .logo, .nav-panel .nav-categories {
        display: none;
      }
      .mobile-nav {
        display: flex;
        width: 100%;
        justify-content: space-around;
        align-items: center;
      }
      .mobile-nav a {
        display: flex;
        flex-direction: column;
        align-items: center;
        font-size: 12px;
        color: var(--text-secondary);
        gap: 2px;
      }
      .mobile-nav i {
        font-size: 20px;
        color: var(--champagne);
      }
      .mobile-cta {
        position: absolute;
        top: -28px;
        left: 50%;
        transform: translateX(-50%);
        background: var(--champagne);
        color: var(--deep-blue);
        width: 50px;
        height: 50px;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        box-shadow: 0 8px 18px rgba(201,169,110,0.4);
        font-size: 22px;
      }
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, #0B1A2E 0%, #162D50 100%);
      padding: 140px 0 100px;
      position: relative;
      overflow: hidden;
      color: var(--silver);
    }
    .hero::before {
      content: "";
      position: absolute;
      width: 400px;
      height: 400px;
      background: radial-gradient(circle, rgba(94,234,212,0.12) 0%, transparent 70%);
      top: -100px;
      right: -100px;
      border-radius: 50%;
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 40px;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 400px;
    }
    .hero-text h1 {
      font-size: 40px;
      font-weight: 700;
      line-height: 1.2;
      color: white;
      margin-bottom: 18px;
    }
    .hero-text h1 span {
      color: var(--champagne);
    }
    .hero-desc {
      font-size: 18px;
      color: var(--silver);
      margin-bottom: 28px;
      opacity: 0.9;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-outline-light {
      border: 1px solid var(--silver);
      color: var(--silver);
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 500;
      transition: all var(--transition);
      background: transparent;
    }
    .btn-outline-light:hover {
      background: rgba(255,255,255,0.1);
      color: white;
    }
    .hero-image {
      flex: 1 1 400px;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 20px 35px rgba(0,0,0,0.5);
    }
    @media (max-width: 768px) {
      .hero {
        padding: 120px 0 80px;
      }
      .hero-text h1 {
        font-size: 32px;
      }
    }
    /* 通用板块 */
    section {
      padding: 80px 0;
    }
    .section-title {
      font-size: 28px;
      font-weight: 600;
      color: var(--deep-blue);
      margin-bottom: 12px;
    }
    .section-sub {
      color: var(--text-secondary);
      margin-bottom: 40px;
    }
    /* 功能卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
      gap: 24px;
    }
    .feature-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--shadow-card);
      transition: all var(--transition);
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 48px;
      height: 48px;
      background: rgba(94,234,212,0.15);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--aurora);
      font-size: 24px;
      margin-bottom: 18px;
    }
    .feature-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 10px;
    }
    /* 场景图文 */
    .scene-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 60px;
      flex-wrap: wrap;
    }
    .scene-img {
      flex: 1 1 300px;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .scene-text {
      flex: 1 1 300px;
    }
    /* 案例卡片 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
      gap: 24px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 20px;
      box-shadow: var(--shadow-card);
    }
    .stat-number {
      font-size: 32px;
      font-weight: 700;
      color: var(--champagne);
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      box-shadow: var(--shadow-card);
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--deep-blue);
    }
    .faq-answer {
      padding: 0 24px 20px;
      color: var(--text-primary);
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    /* CTA 底部 */
    .cta-bottom {
      background: var(--deep-blue);
      color: white;
      text-align: center;
      padding: 70px 20px;
      border-radius: 0;
    }
    .footer {
      background: #0B1A2E;
      color: var(--silver);
      padding: 50px 0 20px;
      font-size: 14px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 30px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      section {
        padding: 60px 0;
      }
    }