/* roulang page: index */
:root {
      --primary: #F04E30;
      --primary-glow: rgba(240, 78, 48, 0.6);
      --secondary: #0A0E27;
      --accent: #F7B731;
      --card-bg: #141832;
      --text-body: #B0B7D1;
      --text-title: #FFFFFF;
      --border-light: rgba(255, 255, 255, 0.08);
      --radius-md: 16px;
      --radius-lg: 24px;
      --shadow-card: 0 20px 35px rgba(0, 0, 0, 0.4);
      --transition-base: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
      --font-mono: 'DIN Alternate', 'Roboto Mono', monospace;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      background-color: var(--secondary);
      color: var(--text-body);
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    h1, h2, h3, h4 {
      color: var(--text-title);
      font-weight: 700;
      letter-spacing: -0.01em;
    }
    h1 {
      font-size: clamp(3rem, 8vw, 5rem);
      font-weight: 900;
      line-height: 1.1;
    }
    h2 {
      font-size: clamp(2rem, 5vw, 3rem);
      margin-bottom: 1rem;
    }
    h3 {
      font-size: 1.5rem;
      font-weight: 600;
    }
    a {
      color: var(--text-body);
      text-decoration: none;
      transition: var(--transition-base);
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
      border-radius: var(--radius-md);
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: 50px;
      font-weight: 600;
      font-size: 1rem;
      letter-spacing: 0.5px;
      transition: var(--transition-base);
      cursor: pointer;
      border: none;
      background: transparent;
      color: white;
      gap: 8px;
    }
    .btn-primary {
      background: var(--primary);
      box-shadow: 0 8px 20px rgba(240, 78, 48, 0.4);
    }
    .btn-primary:hover {
      background: #ff5e40;
      box-shadow: 0 12px 28px var(--primary-glow);
      transform: translateY(-2px);
    }
    .btn-outline {
      border: 1px solid rgba(255,255,255,0.3);
      backdrop-filter: blur(4px);
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.08);
      border-color: white;
      transform: translateY(-2px);
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 999;
      background: rgba(10, 14, 39, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(255,255,255,0.05);
      transition: var(--transition-base);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 76px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 900;
      font-size: 1.6rem;
      color: white;
      letter-spacing: 1px;
    }
    .logo span {
      background: var(--primary);
      padding: 4px 12px;
      border-radius: 30px;
      font-size: 0.9rem;
      font-weight: 600;
      color: white;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--text-body);
      position: relative;
    }
    .nav-links a:hover, .nav-links a.active {
      color: white;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.3s ease;
    }
    .nav-links a:hover::after, .nav-links a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      background: none;
      border: none;
    }
    .hamburger span {
      width: 28px;
      height: 2px;
      background: white;
      transition: var(--transition-base);
    }
    /* 英雄区 */
    .hero {
      padding: 160px 0 100px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      min-height: 90vh;
      display: flex;
      align-items: center;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 20% 30%, rgba(240,78,48,0.15) 0%, rgba(10,14,39,0.85) 70%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .hero-text {
      max-width: 600px;
    }
    .hero-text p {
      font-size: 1.25rem;
      margin: 24px 0 32px;
      color: #d1d5e0;
    }
    .hero-btns {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-visual {
      display: flex;
      justify-content: center;
      align-items: center;
    }
    .energy-ring {
      width: 320px;
      height: 320px;
      border-radius: 50%;
      border: 2px solid rgba(240,78,48,0.4);
      background: radial-gradient(circle, rgba(240,78,48,0.1) 0%, transparent 70%);
      animation: pulse 4s infinite;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    @keyframes pulse {
      0% { transform: scale(0.95); opacity: 0.7; }
      50% { transform: scale(1.05); opacity: 1; border-color: rgba(247,183,49,0.7); }
      100% { transform: scale(0.95); opacity: 0.7; }
    }
    /* 指标看板 */
    .metrics {
      padding: 80px 0;
    }
    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .metric-card {
      background: var(--card-bg);
      backdrop-filter: blur(8px);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-lg);
      padding: 28px 20px;
      text-align: center;
      transition: var(--transition-base);
    }
    .metric-card:hover {
      transform: translateY(-6px);
      border-color: var(--primary);
      box-shadow: 0 20px 30px rgba(240,78,48,0.15);
    }
    .metric-value {
      font-family: var(--font-mono);
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--accent);
      display: flex;
      align-items: baseline;
      justify-content: center;
      gap: 4px;
    }
    .metric-label {
      color: #aab3cc;
      margin-top: 12px;
      font-weight: 500;
    }
    /* 服务矩阵 */
    .services {
      padding: 80px 0;
    }
    .service-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .service-main {
      grid-row: span 2;
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      overflow: hidden;
      border: 1px solid var(--border-light);
      transition: var(--transition-base);
    }
    .service-main:hover {
      border-color: var(--primary);
      box-shadow: 0 25px 40px rgba(0,0,0,0.5);
    }
    .service-main img {
      width: 100%;
      height: 240px;
      object-fit: cover;
    }
    .service-main .service-info {
      padding: 24px;
    }
    .service-small {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 24px;
      border: 1px solid var(--border-light);
      transition: var(--transition-base);
      display: flex;
      flex-direction: column;
    }
    .service-small:hover {
      border-color: var(--primary);
      transform: translateY(-5px);
    }
    .service-icon {
      font-size: 2rem;
      color: var(--primary);
      margin-bottom: 16px;
    }
    /* 对比 */
    .comparison {
      padding: 80px 0;
    }
    .compare-grid {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      gap: 24px;
      align-items: center;
    }
    .compare-col {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 32px;
      border: 1px solid var(--border-light);
    }
    .compare-col.bad {
      opacity: 0.7;
      filter: grayscale(0.3);
    }
    .compare-col.good {
      border-color: var(--primary);
      box-shadow: 0 0 20px rgba(240,78,48,0.2);
    }
    .vs-badge {
      background: var(--accent);
      color: #0A0E27;
      font-weight: 900;
      font-size: 1.4rem;
      width: 70px;
      height: 70px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 0 30px rgba(247,183,49,0.5);
    }
    /* FAQ */
    .faq {
      padding: 80px 0;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      font-size: 1.2rem;
      color: white;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-body);
      padding-left: 12px;
      border-left: 2px solid var(--primary);
      margin-top: 12px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
    }
    /* 表单 */
    .contact {
      padding: 80px 0;
    }
    .form-card {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 48px;
      border: 1px solid var(--border-light);
      max-width: 700px;
      margin: 0 auto;
    }
    .input-group input {
      width: 100%;
      padding: 14px 18px;
      background: #0f132a;
      border: 1px solid var(--border-light);
      border-radius: 40px;
      color: white;
      margin-bottom: 20px;
      transition: var(--transition-base);
    }
    .input-group input:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 12px var(--primary-glow);
    }
    /* 页脚 */
    .footer {
      padding: 60px 0 30px;
      border-top: 1px solid var(--border-light);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 1024px) {
      .hero-content { grid-template-columns: 1fr; text-align: center; }
      .hero-text { max-width: 100%; }
      .metrics-grid { grid-template-columns: repeat(2, 1fr); }
      .compare-grid { grid-template-columns: 1fr; }
      .vs-badge { margin: 20px auto; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .service-grid { grid-template-columns: 1fr; }
      .metrics-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .hero { padding: 120px 0 60px; }
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(10,14,39,0.98);
      backdrop-filter: blur(20px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      transform: translateX(100%);
      transition: transform 0.4s ease;
      z-index: 1000;
    }
    .mobile-menu.open {
      transform: translateX(0);
    }