/* roulang page: index */
@import url('/assets/css/vendor/0b67347532-css2.css');

    :root {
      --bg-primary: #0B0C0E;
      --bg-secondary: #16181C;
      --surface: #1E2026;
      --text-primary: #F2F2F2;
      --text-secondary: #A0A3AD;
      --accent: #D4FF00;
      --accent-glow: rgba(212, 255, 0, 0.3);
      --border: #2A2D35;
      --success: #00C897;
      --warning: #FF5C39;
      --container-max: 1280px;
      --radius-lg: 12px;
      --radius-md: 8px;
    }

    * {
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      margin: 0;
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", "Inter", system-ui, -apple-system, sans-serif;
      background-color: var(--bg-primary);
      color: var(--text-primary);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    .container {
      max-width: var(--container-max);
      margin-left: auto;
      margin-right: auto;
      padding-left: 40px;
      padding-right: 40px;
    }

    @media (max-width: 1024px) {
      .container {
        padding-left: 24px;
        padding-right: 24px;
      }
    }

    @media (max-width: 768px) {
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }

    /* 导航 */
    .nav-bar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      display: flex;
      align-items: center;
      justify-content: center;
      z-index: 50;
      transition: background 0.3s ease, backdrop-filter 0.3s ease;
      border-bottom: 1px solid rgba(255, 255, 255, 0.05);
      background: transparent;
    }

    .nav-scrolled {
      background: rgba(11, 12, 14, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }

    .nav-container {
      max-width: var(--container-max);
      width: 100%;
      margin: 0 auto;
      padding: 0 40px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }

    @media (max-width: 768px) {
      .nav-container {
        padding: 0 16px;
      }
    }

    .logo {
      font-weight: 800;
      font-size: 20px;
      color: var(--text-primary);
      letter-spacing: -0.01em;
      text-decoration: none;
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }

    .nav-link {
      color: var(--text-secondary);
      text-decoration: none;
      font-weight: 500;
      font-size: 16px;
      transition: color 0.2s;
    }

    .nav-link:hover {
      color: var(--accent);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 8px;
    }

    .hamburger span {
      background: var(--text-primary);
      height: 2px;
      width: 24px;
      display: block;
      transition: all 0.3s;
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--bg-primary);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 40px;
      z-index: 45;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.3s;
    }

    .mobile-menu.active {
      display: flex;
      opacity: 1;
      pointer-events: auto;
    }

    .mobile-link {
      color: var(--text-primary);
      font-size: 24px;
      font-weight: 600;
      text-decoration: none;
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
    }

    /* 板块间距 */
    .section-space {
      padding-top: 120px;
      padding-bottom: 120px;
    }

    @media (max-width: 768px) {
      .section-space {
        padding-top: 80px;
        padding-bottom: 80px;
      }
    }

    /* 标题 */
    h1 {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.15;
      letter-spacing: -0.02em;
      margin: 0;
    }

    h2 {
      font-size: 40px;
      font-weight: 600;
      line-height: 1.25;
    }

    h3 {
      font-size: 20px;
      font-weight: 600;
    }

    @media (max-width: 768px) {
      h1 {
        font-size: 36px;
      }
      h2 {
        font-size: 28px;
      }
    }

    .body-text {
      font-size: 16px;
      font-weight: 400;
      color: var(--text-secondary);
      line-height: 1.7;
    }

    .small-label {
      font-size: 13px;
      font-weight: 500;
      letter-spacing: 0.04em;
      text-transform: uppercase;
      color: var(--text-secondary);
    }

    /* 按钮 */
    .btn-primary {
      background: var(--accent);
      color: #0B0C0E;
      font-weight: 700;
      border-radius: var(--radius-md);
      padding: 16px 40px;
      text-decoration: none;
      display: inline-block;
      transition: all 0.25s;
      border: none;
      cursor: pointer;
    }

    .btn-primary:hover {
      background: #E0FF33;
      box-shadow: 0 0 30px var(--accent-glow);
    }

    .btn-secondary {
      background: transparent;
      border: 2px solid var(--border);
      color: var(--text-primary);
      font-weight: 600;
      border-radius: var(--radius-md);
      padding: 16px 40px;
      text-decoration: none;
      display: inline-block;
      transition: all 0.25s;
    }

    .btn-secondary:hover {
      border-color: var(--accent);
      color: var(--accent);
    }

    /* 卡片 */
    .card {
      background: var(--surface);
      border-radius: var(--radius-lg);
      padding: 32px;
      border: 1px solid var(--border);
      transition: transform 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94), border-color 0.3s;
      box-shadow: 0 1px 2px rgba(0,0,0,0.4);
    }

    .card:hover {
      transform: translateY(-4px);
      border-color: var(--accent);
    }

    @media (max-width: 768px) {
      .card {
        padding: 24px;
      }
    }

    /* 动画 */
    .fade-in-up {
      opacity: 0;
      transform: translateY(30px);
      transition: opacity 0.6s ease, transform 0.6s ease;
    }

    .fade-in-up.visible {
      opacity: 1;
      transform: translateY(0);
    }

    .float-animation {
      animation: float 4s ease-in-out infinite;
    }

    @keyframes float {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(-6px); }
    }

    .count-up {
      font-variant-numeric: tabular-nums;
      font-feature-settings: "tnum";
    }

    /* 英雄右侧图形 */
    .hero-graphic {
      position: relative;
      width: 100%;
      height: 400px;
    }

    .arc {
      position: absolute;
      border: 2px solid var(--accent);
      opacity: 0.7;
      border-radius: 50%;
      animation: pulse-line 3s infinite alternate;
    }

    @keyframes pulse-line {
      0% { opacity: 0.5; }
      100% { opacity: 0.9; }
    }

    /* 噪点纹理 */
    .noise-bg {
      position: relative;
    }
    .noise-bg::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image: repeating-radial-gradient(circle at 20% 30%, rgba(255,255,255,0.02) 0, transparent 4px);
      pointer-events: none;
    }

    /* 手风琴 */
    .faq-item {
      background: var(--surface);
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 600;
      background: var(--surface);
    }
    .faq-icon {
      transition: transform 0.35s;
      color: var(--text-secondary);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: var(--bg-secondary);
      padding: 0 20px;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
      color: var(--accent);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 0 20px 20px;
    }