:root {
      --color-primary: #0b1e3a;
      --color-primary-light: #132d55;
      --color-accent: #3A54ED;
      --color-accent-hover: #2f45d4;
      --color-accent-light: #e8ebfd;
      --color-bg: #ffffff;
      --color-bg-alt: #f6f8fc;
      --color-bg-gradient: linear-gradient(135deg, #f0f4ff 0%, #e8ecf9 100%);
      --color-text: #1a2332;
      --color-text-muted: #5a6478;
      --color-text-light: #8f98aa;
      --color-border: #e2e6ee;
      --color-card-bg: #ffffff;
      --color-card-shadow: rgba(10, 30, 60, 0.08);
      --color-card-shadow-hover: rgba(10, 30, 60, 0.14);
      --color-footer-bg: #0b1e3a;
      --color-footer-text: #b0bcca;
      --color-white: #ffffff;
      --color-success: #10b981;
      --color-hero-gradient: linear-gradient(135deg, #0b1e3a 0%, #1a3466 100%);
      --color-tag-bg: rgba(58, 84, 237, 0.08);
      --color-tag-text: var(--color-accent);
      --color-cta-text: var(--color-white);
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 20px;
      --radius-full: 9999px;
      --font-body: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    }

    *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
    html { scroll-behavior: smooth; }
    body {
      font-family: var(--font-body);
      color: var(--color-text);
      background: var(--color-bg);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    a { color: var(--color-accent); text-decoration: none; transition: color 0.2s; }
    a:hover { color: var(--color-accent-hover); }
    img { max-width: 100%; height: auto; display: block; }
    ul { list-style: none; padding: 0; }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 2rem;
    }

    /* === Nav === */
    .site-nav {
      position: fixed;
      top: 0; left: 0; right: 0;
      z-index: 100;
      padding: 0 2rem;
      height: 68px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: rgba(11,30,58,0.7);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border-bottom: 1px solid rgba(255,255,255,0.1);
      transition: background 0.3s, box-shadow 0.3s;
    }
    .site-nav.scrolled {
      background: rgba(11,30,58,0.85);
      box-shadow: 0 2px 20px rgba(0,0,0,0.06);
    }
    .nav-brand {
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .nav-brand img {
      height: 36px;
      width: auto;
    }
    .nav-brand span {
      font-size: 1.15rem;
      font-weight: 700;
      color: var(--color-white);
      letter-spacing: 0.02em;
    }
    .nav-links {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 2rem;
      flex: 1;
    }
    .nav-links a {
      font-size: 0.95rem;
      color: rgba(255,255,255,0.85) !important;
      font-weight: 500;
      transition: color 0.2s;
      position: relative;
    }
    @media (max-width: 768px) {
      .nav-links a { color: var(--color-text) !important; }
      .nav-links a.active { color: var(--color-white) !important; }
      .nav-links a.active::after { display: none; }
      .nav-links a:hover { background-color: var(--color-primary-light); }
      .nav-links a.active { background-color: #0b1e3a; }
    }
    @media (max-width: 768px) {
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--color-white) !important;
    }
    }
    .nav-links a:hover{
      color: rgba(255,255,255,1) !important;
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      right: 0;
      height: 2px;
      background: var(--color-white);
      border-radius: 1px;
    }
    .nav-cta {
      display: inline-flex;
      align-items: center;
      gap: 0.4rem;
      padding: 0.5rem 1.2rem;
      background: var(--color-accent);
      color: var(--color-cta-text);
      border-radius: var(--radius-full);
      font-size: 0.9rem;
      font-weight: 600;
      transition: background 0.2s, transform 0.2s;
    }
    .nav-cta:hover {
      background: var(--color-accent-hover);
      color: var(--color-cta-text);
      transform: translateY(-1px);
    }
    .mobile-toggle {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 4px;
    }
    @media (max-width: 768px) {
    .nav-links a { transition: background-color 0.2s, color 0.2s; }
    .nav-links a:hover,
    .nav-links a.active { background-color: #0b1e3a; color: #ffffff !important; }
    }
    .mobile-toggle span {
      display: block;
      width: 24px;
      height: 2px;
      background: #fff;
      border-radius: 2px;
      transition: all 0.2s;
    }
    @media (max-width: 768px) {
      .site-nav { padding: 0 1rem; }
      .nav-links {
        display: none;
        position: absolute;
        top: 68px;
        left: 0;
        right: 0;
        flex-direction: column;
        gap: 0;
        background: var(--color-bg);
        border-bottom: 1px solid var(--color-border);
        padding: 0.5rem 0;
        box-shadow: 0 8px 24px rgba(0,0,0,0.06);
      }
      .nav-links.open { display: flex; }
      .nav-links a {
        padding: 0.8rem 1.5rem;
        width: 100%;
        border-bottom: 1px solid var(--color-border);
      }
      .nav-links a:last-child { border-bottom: none; }
      .nav-links a.active::after { display: none; }
      .nav-links .nav-cta { margin: 0.5rem 1rem; width: auto; justify-content: center; }
      .mobile-toggle { display: flex; }
    }

    /* === Footer === */
    .site-footer {
      background: var(--color-footer-bg);
      color: var(--color-footer-text);
      padding: 3.5rem 2rem 2rem;
    }
    .footer-grid {
      max-width: 1200px;
      margin: 0 auto;
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2.5rem;
    }
    .footer-brand p {
      margin-top: 1rem;
      font-size: 0.9rem;
      line-height: 1.7;
      max-width: 320px;
    }
    .footer-brand img {
      height: 36px;
      width: auto;
    }
    .footer-col h4 {
      color: var(--color-white);
      font-size: 0.95rem;
      margin-bottom: 1rem;
      font-weight: 600;
    }
    .footer-col a {
      display: block;
      color: var(--color-footer-text);
      font-size: 0.9rem;
      padding: 0.3rem 0;
      transition: color 0.2s;
    }
    .footer-col a:hover { color: var(--color-white); }
    .footer-bottom {
      max-width: 1200px;
      margin: 2.5rem auto 0;
      padding-top: 1.5rem;
      border-top: 1px solid rgba(255,255,255,0.08);
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 0.5rem;
      font-size: 0.85rem;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 2rem;
      }
      .footer-brand { grid-column: 1 / -1; }
      .footer-bottom { flex-direction: column; text-align: center; }
    }
    @media (max-width: 480px) {
      .footer-grid { grid-template-columns: 1fr; }
    }

    /* === Buttons === */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      padding: 0.75rem 1.8rem;
      border-radius: var(--radius-full);
      font-size: 1rem;
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: background 0.25s, transform 0.2s, box-shadow 0.25s;
    }
    .btn:hover { transform: translateY(-2px); }
    .btn-primary {
      background: var(--color-accent);
      color: var(--color-cta-text);
    }
    .btn-primary:hover {
      background: var(--color-accent-hover);
      box-shadow: 0 8px 24px rgba(58, 84, 237, 0.25);
      color: var(--color-cta-text);
    }
    .btn-outline {
      background: transparent;
      color: var(--color-accent);
      border: 1.5px solid var(--color-accent);
    }
    .btn-outline:hover {
      background: var(--color-accent);
      color: var(--color-cta-text);
    }

    /* === Utility === */
    .section-title {
      font-size: 2rem;
      font-weight: 700;
      color: var(--color-primary);
      text-align: center;
      margin-bottom: 0.75rem;
      letter-spacing: -0.01em;
    }
    .section-subtitle {
      text-align: center;
      color: var(--color-text-muted);
      font-size: 1.05rem;
      max-width: 600px;
      margin: 0 auto 2.5rem;
    }
    .text-center { text-align: center; }

    /* === Animations === */
    @keyframes fadeUp {
      from { opacity: 0; transform: translateY(24px); }
      to { opacity: 1; transform: translateY(0); }
    }
    .animate-in {
      animation: fadeUp 0.7s ease-out forwards;
    }
    .delay-1 { animation-delay: 0.1s; }
    .delay-2 { animation-delay: 0.2s; }
    .delay-3 { animation-delay: 0.3s; }