/* roulang page: index */
:root {
      --primary: #1A237E;
      --primary-light: #283593;
      --accent: #D4AF37;
      --accent-hover: #B8960F;
      --bg-page: #F5F7FA;
      --bg-card: #FFFFFF;
      --text-main: #1A1A1A;
      --text-secondary: #5A5A5A;
      --text-muted: #8C8C8C;
      --live-red: #E53935;
      --border-light: #E0E4EC;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 24px rgba(26,35,126,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --transition: 0.2s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-main);
      line-height: 1.5;
      scroll-behavior: smooth;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button {
      cursor: pointer;
      font-family: inherit;
    }

    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background 0.25s ease, box-shadow 0.25s ease, backdrop-filter 0.25s ease;
      height: 72px;
      display: flex;
      align-items: center;
      background: transparent;
    }
    #header.scrolled {
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.08);
    }
    #header .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      display: flex;
      align-items: center;
      font-weight: 700;
      font-size: 1.5rem;
      color: white;
      transition: color 0.2s;
      letter-spacing: 0.5px;
    }
    .logo i {
      margin-right: 8px;
      color: var(--accent);
      font-size: 1.8rem;
    }
    #header.scrolled .logo {
      color: var(--primary);
    }
    #header.scrolled .logo i {
      color: var(--accent);
    }
    .nav-menu {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }
    .nav-menu a {
      font-size: 0.95rem;
      font-weight: 500;
      color: rgba(255,255,255,0.9);
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }
    #header.scrolled .nav-menu a {
      color: var(--text-main);
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--accent);
      transition: width 0.2s ease;
    }
    .nav-menu a:hover::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.6rem;
      color: white;
      transition: color 0.2s;
    }
    #header.scrolled .hamburger {
      color: var(--primary);
    }
    @media (max-width: 768px) {
      .nav-menu {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        gap: 0;
        box-shadow: var(--shadow-md);
        padding: 16px 0;
      }
      .nav-menu.active {
        display: flex;
      }
      .nav-menu a {
        padding: 14px 24px;
        color: var(--text-main);
        border-bottom: 1px solid var(--border-light);
      }
      .hamburger {
        display: block;
      }
      #header.scrolled .nav-menu a {
        color: var(--text-main);
      }
    }

    /* Hero */
    #hero {
      background: linear-gradient(135deg, #1A237E 0%, #283593 100%);
      position: relative;
      overflow: hidden;
      min-height: 90vh;
      display: flex;
      align-items: center;
      color: white;
      padding: 100px 0 80px;
    }
    #hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.2;
      mix-blend-mode: overlay;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }
    .hero-left {
      flex: 6;
    }
    .hero-right {
      flex: 4;
      display: flex;
      justify-content: center;
    }
    .hero-right .mock-card {
      background: rgba(255,255,255,0.12);
      backdrop-filter: blur(16px);
      border-radius: 16px;
      padding: 24px;
      border: 1px solid rgba(255,255,255,0.2);
      width: 100%;
      max-width: 280px;
    }
    .live-badge {
      display: flex;
      align-items: center;
      gap: 8px;
      color: white;
      font-weight: 600;
      margin-bottom: 16px;
    }
    .live-dot {
      width: 10px;
      height: 10px;
      background: var(--live-red);
      border-radius: 50%;
      animation: pulse 1.5s infinite;
    }
    @keyframes pulse { 0% { opacity: 1; transform: scale(1); } 50% { opacity: 0.6; transform: scale(1.2); } 100% { opacity: 1; transform: scale(1); } }
    .mock-teams {
      font-size: 1.4rem;
      font-weight: 700;
      margin-bottom: 8px;
    }
    .mock-score {
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--accent);
    }
    h1 {
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
      max-width: 600px;
    }
    .hero-sub {
      font-size: 1.2rem;
      opacity: 0.9;
      margin-bottom: 32px;
      max-width: 550px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      transition: 0.2s;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-primary:hover { background: var(--accent-hover); }
    .btn-outline {
      border: 2px solid white;
      background: transparent;
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      transition: 0.2s;
    }
    .btn-outline:hover { background: white; color: var(--primary); }

    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
        text-align: center;
      }
      h1 { font-size: 2.2rem; }
      .hero-right { width: 100%; }
    }

    /* sections */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      color: var(--primary);
      text-align: center;
      margin-bottom: 16px;
    }
    .section-sub {
      text-align: center;
      color: var(--text-secondary);
      max-width: 600px;
      margin: 0 auto 48px;
    }

    .features-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .feature-card {
      background: var(--bg-card);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all 0.25s;
      text-align: center;
      min-height: 280px;
      display: flex;
      flex-direction: column;
      align-items: center;
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border: 1px solid var(--accent);
    }
    .feature-icon {
      font-size: 2.5rem;
      color: var(--accent);
      margin-bottom: 20px;
    }
    .feature-card h3 { font-size: 1.3rem; margin-bottom: 12px; }
    .feature-card p { color: var(--text-secondary); }

    .scenario-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .scenario-text { flex: 1; }
    .scenario-img { flex: 1; }
    .scenario-img img {
      border-radius: var(--radius-card);
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    .scenario-text h3 { font-size: 1.8rem; margin-bottom: 16px; color: var(--primary); }
    .scenario-text ul { list-style: none; }
    .scenario-text li { margin-bottom: 10px; display: flex; align-items: center; gap: 10px; }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 24px;
    }
    .stat-card {
      background: #EEF1F8;
      padding: 28px;
      border-radius: var(--radius-card);
      text-align: center;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--accent);
    }

    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .pricing-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: 0.2s;
      position: relative;
      border: 1px solid transparent;
    }
    .pricing-card.popular {
      border: 2px solid var(--accent);
      transform: scale(1.02);
    }
    .badge-popular {
      background: var(--accent);
      color: white;
      padding: 4px 16px;
      border-radius: 20px;
      font-size: 0.8rem;
      position: absolute;
      top: -12px;
      right: 20px;
    }

    .faq-item {
      background: white;
      border-bottom: 1px solid var(--border-light);
      margin-bottom: 8px;
      border-radius: 8px;
    }
    .faq-question {
      padding: 20px;
      font-weight: 500;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: #F9FAFB;
      padding: 0 20px;
    }
    .faq-answer.open {
      max-height: 200px;
      padding: 20px;
    }

    #cta {
      background: linear-gradient(135deg, #1A237E, #D4AF37);
      text-align: center;
      padding: 80px 0;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    footer {
      background: #1A1A1A;
      color: #B0B0B0;
      padding: 60px 0 30px;
    }
    @media (max-width: 1024px) {
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .stats-grid { grid-template-columns: repeat(2,1fr); }
      .pricing-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .features-grid, .stats-grid { grid-template-columns: 1fr; }
      .scenario-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
      section { padding: 70px 0; }
    }