/* roulang page: index */
:root {
      --primary-red: #C8102E;
      --primary-red-hover: #E0123A;
      --deep-black: #1A1A1A;
      --dark-bg: #111111;
      --accent-cyan: #00E5FF;
      --accent-cyan-glow: rgba(0, 229, 255, 0.4);
      --gray-light-bg: #F5F5F7;
      --white: #FFFFFF;
      --card-border: #E5E7EB;
      --text-dark: #1A1A1A;
      --text-body: #4B5563;
      --text-muted: #6B7280;
      --text-light: #B0B0B0;
      --radius-card: 16px;
      --radius-btn: 10px;
      --radius-input: 8px;
      --shadow-card: 0 8px 24px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 16px 36px rgba(0,0,0,0.08);
      --glass-bg: rgba(255,255,255,0.06);
      --glass-border: rgba(255,255,255,0.12);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Inter", "Roboto", sans-serif;
      --transition: 0.25s cubic-bezier(0.25, 0.1, 0.25, 1);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--gray-light-bg);
      color: var(--text-body);
      line-height: 1.7;
      letter-spacing: 0.01em;
      overflow-x: hidden;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 2rem;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 1.5rem;
      }
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 999;
      padding: 1.2rem 0;
      transition: background 0.3s, backdrop-filter 0.3s, padding 0.3s;
      background: transparent;
    }
    .navbar.scrolled {
      background: rgba(26,26,26,0.88);
      backdrop-filter: blur(14px);
      padding: 0.8rem 0;
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 2rem;
    }
    .logo {
      font-size: 1.6rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      color: var(--white);
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .logo-icon {
      font-size: 2rem;
      color: var(--primary-red);
      filter: drop-shadow(0 0 6px rgba(200,16,46,0.6));
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 2.2rem;
      list-style: none;
    }
    .nav-links a {
      color: rgba(255,255,255,0.9);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -5px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--accent-cyan);
      transition: width 0.3s;
    }
    .nav-links a:hover {
      color: var(--white);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .btn-nav {
      background: var(--primary-red);
      color: white;
      padding: 0.7rem 1.8rem;
      border-radius: 40px;
      font-weight: 600;
      font-size: 0.9rem;
      transition: 0.3s;
      border: none;
    }
    .btn-nav:hover {
      background: var(--primary-red-hover);
      box-shadow: 0 0 18px rgba(200,16,46,0.7);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 28px;
      height: 3px;
      background: white;
      border-radius: 4px;
      transition: 0.3s;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(17,17,17,0.97);
      backdrop-filter: blur(15px);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2.5rem;
      z-index: 1000;
      opacity: 0;
      pointer-events: none;
    }
    .mobile-menu.active {
      opacity: 1;
      pointer-events: auto;
      display: flex;
    }
    .mobile-menu a {
      font-size: 2rem;
      color: white;
      font-weight: 600;
    }
    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
    }
    /* Hero */
    .hero {
      height: 100vh;
      min-height: 700px;
      background: linear-gradient(135deg, rgba(17,17,17,0.75) 0%, rgba(26,26,26,0.8) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      display: flex;
      align-items: center;
      position: relative;
      color: white;
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 3rem;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 500px;
    }
    .hero h1 {
      font-size: clamp(2.8rem, 6vw, 4.2rem);
      font-weight: 800;
      letter-spacing: -0.03em;
      line-height: 1.2;
      margin-bottom: 1.5rem;
      color: white;
    }
    .hero h1 span {
      color: var(--accent-cyan);
    }
    .hero p {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 2.5rem;
      max-width: 550px;
    }
    .hero-buttons {
      display: flex;
      gap: 1.2rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary-red);
      color: white;
      padding: 1rem 2.5rem;
      border-radius: 40px;
      font-weight: 700;
      font-size: 1rem;
      transition: 0.3s;
      box-shadow: 0 8px 20px rgba(200,16,46,0.4);
    }
    .btn-primary:hover {
      background: var(--primary-red-hover);
      box-shadow: 0 0 25px rgba(200,16,46,0.7);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
      padding: 1rem 2.5rem;
      border-radius: 40px;
      font-weight: 700;
    }
    .btn-outline:hover {
      background: white;
      color: var(--deep-black);
    }
    .hero-visual {
      flex: 1 1 400px;
      background: rgba(255,255,255,0.05);
      backdrop-filter: blur(10px);
      border-radius: 24px;
      padding: 2rem;
      border: 1px solid rgba(255,255,255,0.15);
      display: flex;
      flex-direction: column;
      gap: 1.5rem;
    }
    .stat-row {
      display: flex;
      justify-content: space-between;
      color: var(--accent-cyan);
      font-weight: 700;
      font-size: 2rem;
    }
    @media (max-width: 768px) {
      .hero-visual {
        display: none;
      }
    }
    section {
      padding: 5rem 0;
    }
    .section-title h2 {
      font-size: 2.6rem;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 1rem;
      letter-spacing: -0.02em;
    }
    .section-title p {
      color: var(--text-muted);
      font-size: 1.1rem;
      max-width: 650px;
      margin: 0 auto 3rem;
    }
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    @media (max-width: 1024px) {
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 640px) {
      .grid-3 {
        grid-template-columns: 1fr;
      }
    }
    .service-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 2.2rem;
      border: 1px solid var(--card-border);
      transition: var(--transition);
      box-shadow: var(--shadow-card);
    }
    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-card-hover);
    }
    .icon-box {
      width: 60px;
      height: 60px;
      background: linear-gradient(135deg, #00E5FF22, #00E5FF44);
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 1.8rem;
      color: var(--accent-cyan);
      font-size: 2rem;
    }
    .dark-section {
      background: linear-gradient(180deg, #111111 0%, #1A1A1A 100%);
      color: white;
    }
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: 20px;
      padding: 2rem;
      text-align: center;
    }
    .big-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--accent-cyan);
      font-family: 'Inter', sans-serif;
    }
    .faq-item {
      background: white;
      border: 1px solid var(--card-border);
      border-radius: 14px;
      margin-bottom: 1rem;
      overflow: hidden;
    }
    .faq-question {
      padding: 1.3rem 2rem;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      color: var(--text-dark);
    }
    .faq-answer {
      padding: 0 2rem 1.3rem;
      color: var(--text-body);
    }
    .cta-band {
      background: #0f0f0f;
      text-align: center;
    }
    .btn-cyan {
      background: var(--accent-cyan);
      color: #0a0a0a;
      font-weight: 700;
      padding: 1.1rem 3rem;
      border-radius: 50px;
      font-size: 1.2rem;
      transition: 0.3s;
    }
    .btn-cyan:hover {
      box-shadow: 0 0 35px var(--accent-cyan-glow);
      transform: scale(1.03);
    }
    footer {
      background: #0B0B0B;
      color: #ccc;
      padding: 4rem 0 2rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }