/* roulang page: index */
:root {
      --primary: #E8380D;
      --primary-glow: rgba(232, 56, 13, 0.25);
      --secondary: #1A1A2E;
      --gold: #F5A623;
      --dark-bg: #0F0F1A;
      --light-bg: #FAFAFA;
      --card-bg-light: #FFFFFF;
      --card-bg-dark: rgba(255, 255, 255, 0.04);
      --text-on-dark: #FFFFFF;
      --text-muted-on-dark: #B0B0C0;
      --text-on-light: #1A1A2E;
      --text-muted-on-light: #555555;
      --border-dark: rgba(255, 255, 255, 0.08);
      --border-light: #E2E8F0;
      --radius-card: 16px;
      --radius-btn: 10px;
      --radius-badge: 20px;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-hover: 0 12px 28px rgba(232,56,13,0.18);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-number: "Inter", "SF Pro Display", system-ui, sans-serif;
      --transition: 0.25s ease;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--light-bg);
      color: var(--text-on-light);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

    img {
      max-width: 100%;
      height: auto;
      display: block;
      border-radius: 8px;
    }

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

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 72px;
      display: flex;
      align-items: center;
      transition: background 0.3s, backdrop-filter 0.3s, box-shadow 0.3s;
      background: transparent;
      backdrop-filter: blur(0px);
    }

    .navbar.scrolled {
      background: rgba(26, 26, 46, 0.95);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.3);
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-weight: 700;
      font-size: 1.8rem;
      background: linear-gradient(135deg, #E8380D, #F5A623);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: -0.5px;
      cursor: pointer;
    }

    .nav-menu {
      display: flex;
      gap: 32px;
      align-items: center;
    }

    .nav-link {
      color: #FFFFFF;
      font-weight: 500;
      font-size: 1rem;
      position: relative;
      padding: 6px 0;
      transition: color 0.2s;
    }

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

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

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }

    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: #FFFFFF;
      border-radius: 4px;
      transition: 0.3s;
    }

    /* 移动端菜单 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(15, 15, 26, 0.98);
      backdrop-filter: blur(12px);
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: flex-start;
      padding-left: 32px;
      gap: 28px;
      transform: translateX(-100%);
      transition: transform 0.35s ease;
      z-index: 999;
    }

    .mobile-menu.open {
      transform: translateX(0);
    }

    .mobile-link {
      font-size: 1.5rem;
      font-weight: 600;
      color: #FFFFFF;
      border-bottom: 2px solid transparent;
    }

    .mobile-link:hover {
      border-bottom-color: var(--primary);
    }

    /* 版块通用 */
    section {
      padding: 100px 0;
    }

    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      margin-bottom: 16px;
      color: var(--text-on-light);
    }

    .section-sub {
      color: var(--text-muted-on-light);
      font-size: 1.1rem;
      margin-bottom: 48px;
    }

    .dark-section {
      background-color: var(--dark-bg);
      color: var(--text-on-dark);
    }

    .dark-section .section-title {
      color: #FFFFFF;
    }

    .dark-section .section-sub {
      color: var(--text-muted-on-dark);
    }

    /* 按钮 */
    .btn {
      display: inline-block;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: all 0.25s;
      cursor: pointer;
      border: none;
      font-size: 1rem;
      letter-spacing: 0.3px;
    }

    .btn-primary {
      background: linear-gradient(135deg, #E8380D, #F5A623);
      color: #FFFFFF;
      box-shadow: 0 6px 18px rgba(232,56,13,0.35);
    }

    .btn-primary:hover {
      filter: brightness(1.15);
      transform: translateY(-2px);
      box-shadow: 0 12px 24px rgba(232,56,13,0.5);
    }

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

    .btn-outline:hover {
      background: rgba(232,56,13,0.08);
    }

    .dark-section .btn-outline {
      border-color: #FFFFFF;
      color: #FFFFFF;
    }

    .dark-section .btn-outline:hover {
      background: rgba(255,255,255,0.1);
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 30% 40%, rgba(232,56,13,0.25) 0%, #0F0F1A 80%);
      color: #FFFFFF;
      padding-top: 72px;
      position: relative;
      overflow: hidden;
    }

    .hero-content {
      display: flex;
      align-items: center;
      gap: 48px;
      flex-wrap: wrap;
    }

    .hero-text {
      flex: 1 1 50%;
    }

    .hero h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-sub {
      font-size: 1.2rem;
      color: #B0B0C0;
      margin-bottom: 32px;
    }

    .hero-badges {
      display: flex;
      gap: 20px;
      margin-top: 24px;
      flex-wrap: wrap;
    }

    .badge {
      background: linear-gradient(135deg, #E8380D, #F5A623);
      padding: 6px 16px;
      border-radius: 20px;
      font-family: var(--font-number);
      font-weight: 700;
      color: #FFFFFF;
      font-size: 1.1rem;
      white-space: nowrap;
    }

    .hero-image {
      flex: 1 1 40%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: 24px;
      min-height: 320px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      border: 1px solid rgba(255,255,255,0.1);
    }

    /* 核心优势卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .advantage-card {
      background: var(--card-bg-light);
      border-radius: var(--radius-card);
      padding: 32px 28px;
      box-shadow: var(--shadow-card);
      transition: all 0.3s;
      border: 1px solid var(--border-light);
    }

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

    .icon-circle {
      width: 48px;
      height: 48px;
      background: rgba(232,56,13,0.1);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-size: 1.6rem;
      margin-bottom: 20px;
    }

    .card-title {
      font-size: 1.3rem;
      font-weight: 600;
      margin-bottom: 12px;
    }

    /* 功能分组 图文穿插 */
    .feature-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 80px;
      flex-wrap: wrap;
    }

    .feature-row.reverse {
      flex-direction: row-reverse;
    }

    .feature-text {
      flex: 1;
    }

    .feature-img {
      flex: 1;
      background-size: cover;
      background-position: center;
      border-radius: 20px;
      min-height: 280px;
    }

    /* 案例卡片带数据徽章 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .case-card {
      background: var(--card-bg-dark);
      backdrop-filter: blur(8px);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-dark);
      position: relative;
    }

    .case-img {
      height: 180px;
      background-size: cover;
      background-position: center;
    }

    .case-body {
      padding: 20px;
    }

    .case-badge {
      position: absolute;
      top: 16px;
      right: 16px;
      background: linear-gradient(135deg, #E8380D, #F5A623);
      color: #fff;
      font-family: var(--font-number);
      font-weight: 700;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.95rem;
    }

    /* FAQ */
    .faq-item {
      background: var(--card-bg-light);
      border-radius: 12px;
      margin-bottom: 12px;
      padding: 16px 24px;
      cursor: pointer;
      border: 1px solid var(--border-light);
      transition: 0.2s;
    }

    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: #555;
      margin-top: 0;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }

    .cta-banner {
      background: linear-gradient(135deg, #E8380D, #F5A623);
      border-radius: 24px;
      padding: 64px 32px;
      text-align: center;
      color: #fff;
    }

    .footer {
      background: #0F0F1A;
      color: #B0B0C0;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }

    @media (max-width: 992px) {
      .cards-grid, .case-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .hero h1 {
        font-size: 2.5rem;
      }
    }

    @media (max-width: 768px) {
      .nav-menu {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .cards-grid, .case-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      section {
        padding: 70px 0;
      }
      .hero-content {
        flex-direction: column;
      }
    }