/* roulang page: index */
:root {
      --charcoal: #1A1A1A;
      --red: #E63946;
      --deep-red: #C1121F;
      --gold: #D4AF37;
      --silver-bg: #F0F2F5;
      --blue-gray: #2B3A42;
      --text-light: #F8F9FA;
      --text-muted: #8A939B;
      --white: #FFFFFF;
      --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
      --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.12);
      --shadow-gold: 0 0 20px rgba(212, 175, 55, 0.3);
      --radius: 8px;
      --radius-btn: 6px;
      --transition: 0.25s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    body {
      font-family: var(--font-sans);
      background-color: var(--charcoal);
      color: var(--blue-gray);
      line-height: 1.7;
      overflow-x: hidden;
    }
    
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }
    
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(26, 26, 26, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(255,255,255,0.05);
      transition: background 0.3s;
    }
    .header.scrolled {
      background: rgba(26, 26, 26, 1);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-size: 1.6rem;
      font-weight: 700;
      color: var(--white);
      letter-spacing: 1px;
    }
    .logo span {
      color: var(--gold);
    }
    .nav-links {
      display: flex;
      gap: 28px;
      align-items: center;
    }
    .nav-links a {
      color: #ccc;
      text-decoration: none;
      font-weight: 500;
      font-size: 0.95rem;
      transition: color var(--transition);
      position: relative;
      padding-bottom: 4px;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--white);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--red);
      transition: width var(--transition);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .btn-nav {
      background: var(--red);
      color: white !important;
      padding: 10px 20px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: background var(--transition), box-shadow var(--transition);
      border: none;
      cursor: pointer;
    }
    .btn-nav:hover {
      background: var(--deep-red);
      box-shadow: var(--shadow-gold);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: white;
      background: none;
      border: none;
      cursor: pointer;
    }
    
    /* 移动端菜单 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(0,0,0,0.95);
      backdrop-filter: blur(20px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      transform: translateX(100%);
      transition: transform 0.35s ease;
      z-index: 999;
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-menu a {
      color: white;
      font-size: 1.3rem;
      font-weight: 600;
      text-decoration: none;
    }
    .mobile-menu .close-btn {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 2rem;
      color: white;
      background: none;
      border: none;
    }
    
    /* 板块通用 */
    section {
      padding: 90px 0;
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--white);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 700px;
      margin: 0 auto 48px;
    }
    
    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      background-blend-mode: overlay;
      background-color: rgba(26, 26, 26, 0.75);
      color: white;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
    }
    .hero h1 {
      font-size: 3.4rem;
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 1.2rem;
    }
    .hero .gold {
      color: var(--gold);
    }
    .hero p {
      font-size: 1.3rem;
      color: #ddd;
      margin-bottom: 2.5rem;
    }
    .btn-group {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--red);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      text-decoration: none;
      transition: all var(--transition);
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      background: var(--deep-red);
      box-shadow: var(--shadow-gold);
    }
    .btn-outline {
      border: 2px solid var(--red);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      text-decoration: none;
      transition: all var(--transition);
    }
    .btn-outline:hover {
      background: rgba(230,57,70,0.15);
    }
    .metric-float {
      display: flex;
      gap: 28px;
      margin-top: 48px;
      flex-wrap: wrap;
    }
    .metric-item {
      background: rgba(255,255,255,0.08);
      backdrop-filter: blur(10px);
      padding: 16px 24px;
      border-radius: 12px;
      border: 1px solid rgba(255,255,255,0.15);
    }
    .metric-number {
      font-size: 2rem;
      font-weight: 800;
      color: var(--gold);
    }
    
    /* 卡片通用 */
    .card {
      background: var(--white);
      border-radius: var(--radius);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    
    /* 核心优势 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 28px;
    }
    .feature-card {
      border-left: 4px solid var(--red);
      background: #1e1e1e;
      color: #ddd;
    }
    .feature-card i {
      font-size: 2rem;
      color: var(--gold);
      margin-bottom: 16px;
    }
    
    /* 服务矩阵 */
    .services-big {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 28px;
      margin-bottom: 36px;
    }
    .service-large {
      display: flex;
      background: #2a2a2a;
      border-radius: var(--radius);
      overflow: hidden;
    }
    .service-large img {
      width: 45%;
      object-fit: cover;
    }
    .service-info {
      padding: 28px;
    }
    .small-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 24px;
    }
    
    /* 解决方案步骤 */
    .steps-vertical {
      display: flex;
      justify-content: space-between;
      position: relative;
      margin: 40px 0;
    }
    .step-item {
      text-align: center;
      flex:1;
    }
    
    /* 案例看板 */
    .stats-board {
      display: flex;
      justify-content: center;
      gap: 48px;
      background: #111;
      padding: 32px;
      border-radius: 16px;
    }
    
    /* FAQ */
    .faq-item {
      background: #1e1e1e;
      border-radius: var(--radius);
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 700;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      color: white;
    }
    .faq-answer {
      padding: 0 24px 20px;
      color: #bbb;
      display: none;
    }
    .faq-item.open .faq-answer {
      display: block;
    }
    
    /* 表单 */
    .contact-form input, .contact-form textarea {
      width: 100%;
      padding: 16px;
      margin-bottom: 16px;
      background: #2a2a2a;
      border: 1px solid #444;
      border-radius: 6px;
      color: white;
    }
    
    /* 页脚 */
    .footer {
      background: #0f0f0f;
      color: #aaa;
    }
    
    @media (max-width: 1024px) {
      .features-grid { grid-template-columns: 1fr 1fr; }
      .small-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .hero h1 { font-size: 2.5rem; }
      .services-big { grid-template-columns: 1fr; }
      .stats-board { flex-direction: column; }
      .steps-vertical { flex-direction: column; }
    }