/* roulang page: index */
/* ----- 设计变量 & 全局重置 ----- */
    :root {
      --primary: #0A1F3F;      /* 深蓝黑 · 战场夜空 */
      --accent: #00C2BA;       /* 电竞青 · 胜利光芒 */
      --highlight: #FF5E3A;    /* 橙红 · 竞技热血 */
      --bg: #F4F7FC;
      --card-bg: #FFFFFF;
      --border-light: #E8ECF1;
      --text-main: #1A2332;
      --text-muted: #5A6878;
      --shadow-sm: 0 4px 20px rgba(10, 31, 63, 0.06);
      --shadow-hover: 0 8px 30px rgba(10, 31, 63, 0.12);
      --radius-lg: 12px;
      --radius-md: 8px;
      --transition: all 0.25s ease;
      --max-width: 1280px;
      --header-height: 72px;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
      background-color: var(--bg);
      color: var(--text-main);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

    a {
      text-decoration: none;
      color: inherit;
    }

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

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 20px;
    }

    /* ----- 导航栏（固定顶部·白底）----- */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(8px);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
      z-index: 999;
      display: flex;
      align-items: center;
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
    }

    .logo-icon {
      width: 36px;
      height: 36px;
      background: var(--accent);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 2L2 22h20L12 2zm0 4.5L18.5 20h-13L12 6.5z"/></svg>') center/contain no-repeat;
      background: var(--accent);
    }

    .nav-links {
      display: flex;
      gap: 2rem;
      font-weight: 500;
      color: var(--text-main);
    }

    .nav-links a {
      position: relative;
      padding: 6px 0;
      transition: color 0.2s;
    }

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

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

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

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

    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--primary);
      border-radius: 4px;
      transition: var(--transition);
    }

    /* 移动端菜单 */
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 300px;
        height: 100vh;
        background: rgba(10,31,63,0.97);
        backdrop-filter: blur(12px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 2.5rem;
        transition: right 0.4s ease;
        color: white;
        font-size: 1.5rem;
      }
      .nav-links.active {
        right: 0;
      }
      .nav-links a {
        color: white;
      }
      .hamburger {
        display: flex;
        z-index: 1001;
      }
    }

    /* ----- 板块通用 ----- */
    section {
      padding: 90px 0;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 700;
      margin-bottom: 1.5rem;
      color: var(--primary);
      letter-spacing: -0.3px;
    }

    .section-sub {
      color: var(--text-muted);
      margin-bottom: 3rem;
      font-size: 1.1rem;
    }

    /* ----- Hero 首屏 ----- */
    .hero {
      padding-top: calc(var(--header-height) + 60px);
      display: flex;
      align-items: center;
      gap: 3rem;
      min-height: 85vh;
    }

    .hero-left {
      flex: 1;
    }

    .hero-right {
      flex: 1;
      position: relative;
      border-radius: var(--radius-lg);
      overflow: hidden;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 420px;
    }

    .hero-right::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(10,31,63,0.7) 0%, rgba(0,194,186,0.2) 100%);
    }

    .hero h1 {
      font-size: 3.25rem;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 1.25rem;
      color: var(--primary);
    }

    .hero-highlight {
      color: var(--accent);
    }

    .hero-desc {
      font-size: 1.2rem;
      color: var(--text-muted);
      margin-bottom: 2rem;
    }

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

    .btn-primary {
      background: var(--accent);
      color: white;
      border: none;
      padding: 0.85rem 2.2rem;
      border-radius: var(--radius-md);
      font-weight: 600;
      cursor: pointer;
      transition: var(--transition);
      box-shadow: 0 4px 14px rgba(0,194,186,0.3);
    }

    .btn-primary:hover {
      background: #009C96;
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(0,194,186,0.4);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--accent);
      color: var(--accent);
      padding: 0.8rem 2.1rem;
      border-radius: var(--radius-md);
      font-weight: 600;
      transition: var(--transition);
    }

    .btn-outline:hover {
      background: rgba(0,194,186,0.08);
    }

    .stats-bar {
      display: flex;
      gap: 2.5rem;
      margin-top: 2.5rem;
    }

    .stat-item h3 {
      font-size: 2rem;
      color: var(--highlight);
      font-weight: 700;
    }

    @media (max-width: 1024px) {
      .hero {
        flex-direction: column;
        text-align: center;
      }
      .hero-right {
        width: 100%;
        min-height: 300px;
      }
      .stats-bar {
        justify-content: center;
      }
    }

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

    .adv-card {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 2rem;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border: 1px solid var(--border-light);
    }

    .adv-card:hover {
      box-shadow: var(--shadow-hover);
      border-top: 4px solid var(--accent);
    }

    .adv-icon {
      font-size: 2.2rem;
      color: var(--accent);
      margin-bottom: 1.2rem;
    }

    @media (max-width: 1024px) {
      .advantages-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 640px) {
      .advantages-grid { grid-template-columns: 1fr; }
    }

    /* 案例瀑布流 */
    .cases-masonry {
      columns: 3;
      column-gap: 20px;
    }

    .case-card {
      break-inside: avoid;
      margin-bottom: 20px;
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .case-img {
      position: relative;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      transition: transform 0.4s;
    }
    .case-card:hover .case-img img {
      transform: scale(1.04);
    }
    .case-content {
      padding: 1.2rem;
    }

    @media (max-width: 768px) {
      .cases-masonry { columns: 2; }
    }
    @media (max-width: 520px) {
      .cases-masonry { columns: 1; }
    }

    /* 方案对比 */
    .compare-panel {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2rem;
    }
    .compare-card {
      background: white;
      border-radius: var(--radius-lg);
      padding: 2rem;
      box-shadow: var(--shadow-sm);
    }
    .compare-card.highlight {
      border: 2px solid var(--accent);
      background: #F0FDFC;
    }
    .compare-list li {
      display: flex;
      align-items: center;
      gap: 10px;
      margin: 0.8rem 0;
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      box-shadow: 0 2px 8px rgba(0,0,0,0.03);
    }
    .faq-question {
      padding: 1.2rem 1.5rem;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      padding: 0 1.5rem 1.2rem;
      display: none;
      color: var(--text-muted);
    }
    .faq-item.active .faq-answer { display: block; }

    /* 联系表单 */
    .contact-row {
      display: flex;
      gap: 3rem;
      background: white;
      border-radius: var(--radius-lg);
      padding: 2.5rem;
    }
    .form-input {
      width: 100%;
      padding: 0.9rem;
      margin-bottom: 1rem;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      background: #F9FBFD;
    }
    .btn-highlight {
      background: var(--highlight);
      color: white;
      border: none;
      padding: 0.9rem 2rem;
      border-radius: var(--radius-md);
      font-weight: 600;
      cursor: pointer;
    }
    @media (max-width: 768px) {
      .contact-row, .compare-panel { flex-direction: column; grid-template-columns: 1fr; }
    }

    footer {
      background: var(--primary);
      color: #ccd6e0;
      padding: 3rem 0;
    }