/* General Reset */
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
      font-family: 'Roboto', sans-serif;
    }

    body {
      background-color: #f2f2f2; /* Light-gray background */
      color: #ffffff;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
    }

    header {
      background-color: #1e90ff; /* Light-blue */
      padding: 1.5rem;
      text-align: center;
    }

    header h1 {
      font-size: 1.8rem;
      margin-bottom: 0.5rem;
    }

    nav {
      margin-top: 0.5rem;
    }

    nav a {
      color: #ffffff;
      margin: 0 1rem;
      text-decoration: none;
      font-weight: bold;
    }

    nav a:hover {
      text-decoration: underline;
    }

    main {
      flex: 1;
      padding: 2rem;
      display: flex;
      flex-direction: column;
      gap: 2rem;
    }

    section {
      background-color: #ffffff;
      padding: 1.5rem;
      border-radius: 12px;
      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
      color: #333;
    }

    section h2 {
      color: #1e90ff;
      margin-bottom: 1rem;
      font-size: 1.5rem;
    }

    .js_link {
      color: #1e90ff;
      text-decoration: none;
      margin-top: 3px;
    }

    .lessons, .games {
      display: grid;
      gap: 1rem;
    }

    .lesson, .game {
      background-color: #f9f9f9;
      border-radius: 10px;
      padding: 1rem;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
    }

    .lesson:hover, .game:hover {
      transform: translateY(-5px);
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    }

    button {
      background-color: hsl(210, 100%, 56%);
      color: #ffffff;
      border: none;
      padding: 0.7rem 1.2rem;
      border-radius: 8px;
      cursor: pointer;
      transition: background-color 0.3s ease;
      font-family: Arial, Helvetica, sans-serif;
      font-size: 14px;
      margin-top: 3px;
      margin-bottom: 8px;
    }

    button:hover {
      background-color: hsl(209, 100%, 46%);
    }

    button:active {
      background-color: hsl(209, 100%, 36%);
    }

    footer {
      background-color: #1e90ff;
      color: #ffffff;
      text-align: center;
      padding: 1rem;
      font-size: 0.9rem;
    }

    footer a {
      color: #ffffff;
      margin: 0 0.5rem;
      text-decoration: none;
    }

    footer a:hover {
      text-decoration: underline;
    }

    /* Responsive Design */
    @media (max-width: 768px) {
      main {
        padding: 1rem;
      }

      header h1 {
        font-size: 1.5rem;
      }

      nav a {
        display: inline-block;
        margin: 0.3rem;
      }
    }