:root {
      --accent: #2563eb;
      --accent-hover: #1d4ed8;
      --background: #0f172a;
      --surface: #1e293b;
      --text: #f0f0f0;
      --text-muted: #ffffff;
      --border: #2563eb;
      --shadow-light: rgba(37, 99, 235, 0.15);
      --success: #00c781;
      --banner-bg: #2563eb;
      --banner-text: #f9fbff;
      --primary: #0ea5e9;
      --primary-dark: #0369a1;
    }

    *, *::before, *::after {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      font-family: 'Poppins', Arial, sans-serif;
      background-color: var(--background);
      color: var(--text);
      min-height: 100vh;
      display: flex;
      flex-direction: column;
    }

    a {
      color: var(--accent);
      text-decoration: none;
      transition: color 0.3s ease;
    }

    a:hover,
    a:focus {
      color: var(--accent-hover);
      outline: none;
      text-shadow: 0 0 8px var(--accent-hover);
    }

    /* Header */
    header {
      width: 100%;
      background: var(--surface);
      border-bottom: 2px solid var(--border);
      box-shadow: 0 2px 10px var(--shadow-light);
      position: sticky;
      top: 0;
      z-index: 100;
    }

    .header-inner {
      width: 100%;
      padding: 1rem 2rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    header h1 {
      margin: 0;
      font-weight: 700;
      font-size: 2rem;
      color: #004a99;
    }

    nav {
      display: flex;
      gap: 2rem;
    }

    nav a {
      font-weight: 600;
      font-size: 1.1rem;
      color: #004a99;
      padding-bottom: 2px;
      border-bottom: 2px solid transparent;
      transition: color 0.3s ease, border-color 0.3s ease;
      position: relative;
    }

    nav a:hover,
    nav a:focus,
    nav a.active {
      color: #002f66;
      border-color: #002f66;
    }

    /* Banner */
    .banner {
      background-color: var(--banner-bg);
      color: var(--banner-text);
      text-align: center;
      padding: 3rem 1rem;
      font-size: 1.6rem;
      font-weight: 600;
      box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
      border-radius: 0 0 16px 16px;
      margin-bottom: 2.5rem;
    }

    /* Main */
    main {
      max-width: 900px;
      margin: 0 auto 5rem auto;
      padding: 2.5rem 2.5rem 3rem 2.5rem;
      background-color: var(--surface);
      border-radius: 16px;
      box-shadow: 0 0 30px var(--shadow-light);
      display: flex;
      flex-direction: column;
      gap: 3rem;
    }

    main h2 {
      color: var(--accent);
      font-weight: 700;
      font-size: 2.6rem;
      margin: 0;
      text-align: center;
      letter-spacing: 0.04em;
    }

    main p {
      color: #ffffff;
      font-size: 1.2rem;
      max-width: 700px;
      margin: 1rem auto 0 auto;
      line-height: 1.8;
      text-align: center;
    }

    section {
      padding: 0 1rem;
    }

    h3 {
      color: var(--accent);
      font-weight: 600;
      font-size: 1.8rem;
      margin-bottom: 1.2rem;
      text-align: center;
      letter-spacing: 0.03em;
    }

    ul {
      list-style: none;
      padding: 0;
      max-width: 700px;
      margin: 0 auto;
      color: #ffffff;
    }

    ul li {
      position: relative;
      padding-left: 2rem;
      margin-bottom: 1.2rem;
      font-weight: 600;
      font-size: 1.1rem;
      line-height: 1.4;
    }

    ul li::before {
      content: "✓";
      position: absolute;
      left: 0;
      color: var(--success);
      font-weight: 900;
      font-size: 1.4rem;
      line-height: 1;
      top: 0.15rem;
    }

    /* Footer */
    footer {
      background-color: var(--background);
      border-top: 2px solid var(--border);
      color: #888;
      font-size: 0.9rem;
      text-align: center;
      padding: 1.5rem 2rem;
      box-shadow: 0 -2px 10px var(--shadow-light);
      margin-top: auto;
    }

    /* Responsive */
    @media (max-width: 768px) {
      .header-inner {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
      }

      nav {
        flex-wrap: wrap;
        gap: 1rem;
      }

      main {
        margin: 0 1rem 4rem 1rem;
        padding: 2rem 1.5rem 2.5rem 1.5rem;
        gap: 2rem;
      }

      main h2 {
        font-size: 2rem;
      }

      main p {
        font-size: 1rem;
      }

      h3 {
        font-size: 1.5rem;
      }

      ul li {
        font-size: 1rem;
      }
    }