/* roulang page: index */
:root {
      --sport-red: #C8102E;
      --sport-red-hover: #A00D24;
      --charcoal-dark: #1E1E1E;
      --charcoal-footer: #111111;
      --gray-bg: #F5F5F5;
      --card-bg: #FAFAFA;
      --white: #FFFFFF;
      --text-dark: #1E1E1E;
      --text-body: #333333;
      --text-muted: #666666;
      --text-light-gray: #CCCCCC;
      --border-light: #E0E0E0;
      --border-subtle: #EEEEEE;
      --shadow-card: 0 2px 8px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.12);
      --radius-card: 8px;
      --radius-btn: 6px;
      --container-max: 1200px;
      --gap-section: 100px;
      --mobile-gap: 60px;
      --nav-height: 72px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: "Inter", "SF Pro Display", "PingFang SC", "Microsoft YaHei", sans-serif;
      background-color: var(--white);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
    }
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: var(--white);
      border-bottom: 1px solid var(--border-subtle);
      z-index: 1000;
      display: flex;
      align-items: center;
    }
    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--charcoal-dark);
      letter-spacing: -0.5px;
    }
    .logo span {
      color: var(--sport-red);
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-size: 16px;
      font-weight: 500;
      color: var(--charcoal-dark);
      transition: color 0.2s;
      white-space: nowrap;
    }
    .nav-links a:hover {
      color: var(--sport-red);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      display: block;
      width: 24px;
      height: 2px;
      background: var(--sport-red);
      border-radius: 2px;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--charcoal-dark);
      z-index: 999;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 32px;
    }
    .mobile-menu.active {
      display: flex;
    }
    .mobile-menu a {
      font-size: 22px;
      color: var(--white);
      font-weight: 500;
      letter-spacing: 1px;
    }
    .mobile-close {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 32px;
      color: var(--white);
      background: none;
      border: none;
      cursor: pointer;
      line-height: 1;
    }

    /* 通用区块间距 */
    section {
      padding: var(--gap-section) 0;
    }
    @media (max-width: 768px) {
      section {
        padding: var(--mobile-gap) 0;
      }
      :root {
        --gap-section: 60px;
      }
    }
    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .section-title h2 {
      font-size: 36px;
      font-weight: 600;
      color: var(--charcoal-dark);
      line-height: 1.3;
      display: inline-block;
      position: relative;
      margin-bottom: 8px;
    }
    .section-title h2::after {
      content: '';
      display: block;
      width: 40px;
      height: 2px;
      background: var(--sport-red);
      margin: 16px auto 0;
    }

    /* Hero */
    #hero {
      height: 100vh;
      min-height: 650px;
      background: linear-gradient(135deg, #1E1E1E 0%, #0A0A0A 100%);
      position: relative;
      overflow: hidden;
      display: flex;
      align-items: center;
      padding-top: var(--nav-height);
    }
    .hero-bg {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      opacity: 0.4;
      z-index: 0;
    }
    .hero-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      position: relative;
      z-index: 2;
    }
    .hero-left {
      flex: 0 0 50%;
      padding-right: 24px;
    }
    .hero-left h1 {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.15;
      color: var(--white);
      margin-bottom: 24px;
    }
    .hero-left p {
      font-size: 18px;
      color: var(--text-light-gray);
      margin-bottom: 40px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--sport-red);
      color: var(--white);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      display: inline-flex;
      align-items: center;
      transition: 0.2s;
      border: 2px solid var(--sport-red);
    }
    .btn-primary:hover {
      background: var(--sport-red-hover);
      border-color: var(--sport-red-hover);
      transform: translateY(-2px);
      box-shadow: 0 8px 16px rgba(200,16,46,0.3);
    }
    .btn-outline {
      background: transparent;
      color: var(--white);
      border: 2px solid var(--sport-red);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.2s;
    }
    .btn-outline:hover {
      background: var(--sport-red);
      transform: translateY(-2px);
    }
    .hero-right {
      flex: 0 0 50%;
      display: flex;
      justify-content: flex-end;
    }
    .hero-image {
      width: 85%;
      max-width: 500px;
      border: 8px solid var(--white);
      box-shadow: 0 12px 32px rgba(0,0,0,0.4);
      transform: rotate(1deg);
    }

    /* 服务 1+2 布局 */
    .services-grid {
      display: flex;
      gap: 24px;
      align-items: stretch;
    }
    .service-large {
      flex: 0 0 calc(50% - 12px);
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: all 0.25s ease;
    }
    .service-large:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-2px);
    }
    .service-small-group {
      flex: 0 0 calc(50% - 12px);
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .service-small {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: all 0.25s ease;
    }
    .service-small:hover {
      box-shadow: var(--shadow-card-hover);
    }
    .service-icon {
      width: 48px;
      height: 48px;
      color: var(--sport-red);
      margin-bottom: 20px;
    }
    .service-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 12px;
      color: var(--charcoal-dark);
    }
    .service-card p {
      color: var(--text-body);
      margin-bottom: 16px;
    }
    .text-link {
      color: var(--sport-red);
      font-weight: 500;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      transition: 0.2s;
    }
    .text-link::after {
      content: '';
      display: inline-block;
      width: 0;
      height: 0;
      transition: 0.2s;
    }
    .text-link:hover::after {
      content: '→';
      margin-left: 4px;
    }

    /* 数据横条 */
    #advantages {
      background: var(--sport-red);
      padding: 60px 0;
    }
    .stats-grid {
      display: flex;
      justify-content: space-around;
      align-items: center;
      flex-wrap: wrap;
      gap: 32px;
      text-align: center;
    }
    .stat-item {
      display: flex;
      flex-direction: column;
      align-items: center;
    }
    .stat-number {
      font-size: 56px;
      font-weight: 700;
      color: var(--white);
      line-height: 1.1;
    }
    .stat-divider {
      width: 20px;
      height: 1px;
      background: rgba(255,255,255,0.5);
      margin: 12px 0;
    }
    .stat-label {
      font-size: 14px;
      color: rgba(255,255,255,0.85);
      font-weight: 400;
    }

    /* 案例网格 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }
    .case-card {
      position: relative;
      border-radius: 0;
      overflow: hidden;
      height: 280px;
    }
    .case-card img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }
    .case-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      padding: 24px;
      background: linear-gradient(transparent 60%, rgba(0,0,0,0.75));
      color: white;
      transition: 0.25s;
    }
    .case-card:hover .case-overlay {
      background: linear-gradient(transparent 40%, rgba(0,0,0,0.85));
    }
    .case-title {
      font-size: 18px;
      font-weight: 600;
      margin-bottom: 4px;
      transition: transform 0.2s;
    }
    .case-card:hover .case-title {
      transform: translateY(-4px);
    }
    .case-tag {
      font-size: 14px;
      color: #ddd;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      width: 100%;
      text-align: left;
      padding: 20px 0;
      font-size: 18px;
      font-weight: 600;
      color: var(--charcoal-dark);
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: transparent;
      border: none;
      cursor: pointer;
    }
    .faq-icon {
      font-size: 22px;
      transition: transform 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: #F9F9F9;
      padding: 0 24px;
      border-radius: 0 0 8px 8px;
      color: var(--text-body);
      line-height: 1.8;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 20px 24px;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA */
    #contact {
      background: var(--charcoal-dark);
      color: var(--white);
      text-align: center;
    }
    .contact-info {
      margin-top: 32px;
      display: flex;
      justify-content: center;
      gap: 40px;
      flex-wrap: wrap;
    }
    .contact-item {
      display: flex;
      align-items: center;
      gap: 8px;
    }

    /* Footer */
    .site-footer {
      background: var(--charcoal-footer);
      color: #AAAAAA;
      padding: 60px 0 0;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      margin-bottom: 40px;
    }
    .footer-col h4 {
      color: white;
      font-weight: 600;
      margin-bottom: 16px;
    }
    .footer-col a {
      display: block;
      color: #AAAAAA;
      margin-bottom: 8px;
      transition: 0.2s;
    }
    .footer-col a:hover {
      color: var(--sport-red);
    }
    .copyright {
      background: #000;
      text-align: center;
      padding: 16px 0;
      font-size: 13px;
      color: #666;
    }

    @media (max-width: 1024px) {
      .hero-left h1 {
        font-size: 40px;
      }
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .hero-container {
        flex-direction: column;
        text-align: center;
      }
      .hero-left, .hero-right {
        flex: 1;
        width: 100%;
      }
      .hero-left {
        padding-right: 0;
        margin-bottom: 32px;
      }
      .hero-right {
        justify-content: center;
      }
      .services-grid {
        flex-direction: column;
      }
      .service-large, .service-small-group {
        flex: auto;
        width: 100%;
      }
      .cases-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }