/* roulang page: index */
:root {
      --primary: #1E8A3E;
      --primary-dark: #167030;
      --accent: #D4FF00;
      --bg-light: #F4F7F5;
      --bg-dark: #0F1419;
      --bg-dark-gradient: linear-gradient(135deg, #0F1419 0%, #1A2E1F 100%);
      --text-primary: #1F2937;
      --text-secondary: #4B5563;
      --text-light: #F9FAFB;
      --text-muted: #9CA3AF;
      --card-bg: #FFFFFF;
      --border-light: #E5E7EB;
      --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.06);
      --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.12);
      --shadow-glow: 0 0 12px rgba(30, 138, 62, 0.4);
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-pill: 50px;
      --radius-sm: 12px;
      --transition: 0.3s ease;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Roboto', sans-serif;
      --max-width: 1280px;
      --header-height: 80px;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg-light);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    a {
      text-decoration: none;
      color: inherit;
    }

    button, input {
      font-family: inherit;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航栏 - 搜索主导毛玻璃效果 */
    .header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(15, 20, 25, 0.88);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
      height: var(--header-height);
      display: flex;
      align-items: center;
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
      gap: 24px;
    }

    .logo {
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.6rem;
      color: #FFFFFF;
      display: flex;
      align-items: center;
      gap: 8px;
      white-space: nowrap;
      letter-spacing: -0.3px;
    }
    .logo-icon {
      font-size: 1.8rem;
      filter: drop-shadow(0 2px 4px rgba(0,0,0,0.3));
    }

    .search-wrapper {
      flex: 1;
      max-width: 480px;
      position: relative;
      margin: 0 16px;
    }
    .search-input {
      width: 100%;
      background: rgba(255,255,255,0.95);
      border: none;
      border-radius: 30px;
      padding: 12px 20px 12px 48px;
      font-size: 0.95rem;
      color: #1F2937;
      outline: none;
      box-shadow: 0 4px 12px rgba(0,0,0,0.1);
      transition: var(--transition);
    }
    .search-input::placeholder {
      color: #9CA3AF;
    }
    .search-input:focus {
      box-shadow: 0 0 0 3px rgba(30,138,62,0.3), 0 6px 18px rgba(0,0,0,0.15);
    }
    .search-icon {
      position: absolute;
      left: 18px;
      top: 50%;
      transform: translateY(-50%);
      color: var(--primary);
      font-size: 1.3rem;
    }

    .nav-links {
      display: flex;
      gap: 28px;
      font-size: 0.9rem;
      font-weight: 500;
      color: #D1D5DB;
      letter-spacing: 0.3px;
    }
    .nav-links a {
      transition: color 0.2s;
      white-space: nowrap;
    }
    .nav-links a:hover {
      color: var(--accent);
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      color: white;
      font-size: 1.8rem;
      cursor: pointer;
    }

    /* Hero 双栏 */
    .hero {
      background: var(--bg-light);
      padding: 0;
      min-height: 75vh;
      display: flex;
      align-items: center;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .hero-left h1 {
      font-family: var(--font-heading);
      font-size: 3rem;
      font-weight: 800;
      line-height: 1.2;
      letter-spacing: -0.5px;
      color: #0F1419;
      margin-bottom: 16px;
    }
    .hero-left .subtitle {
      font-size: 1.2rem;
      color: #4B5563;
      margin-bottom: 32px;
      line-height: 1.6;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
      padding: 14px 36px;
      border-radius: var(--radius-pill);
      font-weight: 600;
      font-size: 1.1rem;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      cursor: pointer;
      transition: var(--transition);
      box-shadow: 0 4px 12px rgba(30,138,62,0.3);
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      box-shadow: 0 0 16px rgba(212,255,0,0.5);
      transform: scale(1.03);
    }
    .hero-right {
      position: relative;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-md);
      background: #0F1419;
    }
    .hero-img {
      width: 100%;
      height: 420px;
      object-fit: cover;
      display: block;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(15,20,25,0.7) 0%, rgba(26,46,31,0.4) 100%);
    }

    /* 通用板块 */
    .section {
      padding: 80px 0;
    }
    .section-title {
      font-family: var(--font-heading);
      font-size: 2.25rem;
      font-weight: 700;
      margin-bottom: 16px;
      color: #0F1419;
    }
    .section-desc {
      color: #6B7280;
      font-size: 1.1rem;
      max-width: 700px;
      margin-bottom: 40px;
    }

    /* 亮点网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .feature-card {
      background: var(--card-bg);
      padding: 32px 24px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: left;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .feature-icon {
      font-size: 2.4rem;
      color: var(--primary);
      margin-bottom: 16px;
    }
    .feature-card h3 {
      font-size: 1.3rem;
      font-weight: 700;
      margin-bottom: 8px;
    }

    /* 视频瀑布流 */
    .video-masonry {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .video-card {
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .video-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
    }
    .video-thumb {
      position: relative;
      overflow: hidden;
    }
    .video-thumb img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
      transition: transform 0.4s;
    }
    .video-card:hover .video-thumb img {
      transform: scale(1.05);
    }
    .duration {
      position: absolute;
      right: 12px;
      top: 12px;
      background: rgba(0,0,0,0.7);
      color: white;
      padding: 4px 10px;
      border-radius: 20px;
      font-size: 0.8rem;
    }
    .play-icon {
      position: absolute;
      left: 50%;
      top: 50%;
      transform: translate(-50%,-50%);
      font-size: 3rem;
      color: white;
      opacity: 0.9;
      text-shadow: 0 4px 12px black;
      transition: 0.2s;
    }
    .video-card:hover .play-icon {
      color: var(--accent);
    }
    .video-info {
      padding: 18px;
    }
    .video-info h4 {
      font-weight: 700;
      margin-bottom: 6px;
    }
    .video-info p {
      color: #6B7280;
      font-size: 0.9rem;
    }

    /* 战术对比 */
    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    .compare-card {
      background: white;
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-sm);
    }
    .compare-card.highlight {
      border: 2px solid var(--primary);
      background: #F0FDF4;
    }
    .compare-item {
      display: flex;
      justify-content: space-between;
      padding: 12px 0;
      border-bottom: 1px solid var(--border-light);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      width: 100%;
      background: #F9FAFB;
      border: none;
      padding: 20px 16px;
      text-align: left;
      font-weight: 700;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      transition: background 0.3s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: white;
      padding: 0 16px;
    }
    .faq-item.active .faq-question {
      background: white;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px;
    }

    /* CTA */
    .cta-dark {
      background: var(--bg-dark-gradient);
      color: white;
      text-align: center;
      padding: 80px 24px;
      border-radius: 32px;
      margin: 60px 0;
    }

    /* 页脚 */
    .footer {
      background: #0F1419;
      color: #D1D5DB;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
    }
    .footer a:hover {
      color: var(--accent);
    }

    @media (max-width: 1024px) {
      .hero-grid, .video-masonry { grid-template-columns: 1fr; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .compare-grid { grid-template-columns: 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links, .search-wrapper { display: none; }
      .hamburger { display: block; }
      .hero-left h1 { font-size: 2rem; }
      .features-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }