/* Importing Google Fonts is not allowed, so using system fonts similar to Poppins and Roboto */
    :root {
        --main-color: #0A66C2;
        --secondary-color: #4CAF50;
        --accent-color: #FF9800;
        --background-gradient: linear-gradient(135deg, #0A66C2, #6F38C7);
        --text-color: #FFFFFF;
        --background-color: #1E1E1E;
        --font-family: 'Roboto', sans-serif;
        --header-font-family: 'Poppins', sans-serif;
    }

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

    body {
        font-family: var(--font-family);
        background: var(--background-gradient);
        color: var(--text-color);
        line-height: 1.6;
        min-height: 100vh;
        display: flex;
        flex-direction: column;
    }

    /* Navigation Bar */
    .navbar {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        background-color: rgba(30, 30, 30, 0.9);
        color: var(--text-color);
        padding: 15px 30px;
        display: flex;
        justify-content: space-between;
        align-items: center;
        z-index: 1000;
        box-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
    }

    .navbar .logo {
        font-family: var(--header-font-family);
        font-size: 1.5rem;
        font-weight: bold;
    }

    .navbar .login {
        background-color: var(--secondary-color);
        padding: 8px 16px;
        border-radius: 5px;
        text-decoration: none;
        color: var(--text-color);
        transition: background-color 0.3s ease;
    }

    .navbar .login:hover {
        background-color: var(--accent-color);
    }

    /* Main Container */
    .container {
        display: grid;
        grid-template-columns: 1fr 3fr;
        gap: 20px;
        padding: 100px 50px 50px 50px;
        max-width: 1200px;
        margin: 0 auto;
    }

    /* Sidebar */
    .sidebar {
        background-color: rgba(30, 30, 30, 0.8);
        padding: 20px;
        border-radius: 10px;
        box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    }

    .sidebar .tab-item {
        display: block;
        padding: 10px 15px;
        margin-bottom: 10px;
        background-color: var(--background-color);
        color: var(--text-color);
        border-radius: 5px;
        text-decoration: none;
        transition: transform 0.2s ease, background-color 0.3s ease;
        font-size: 1rem;
    }

    .sidebar .tab-item:hover {
        transform: scale(1.05);
        background-color: var(--secondary-color);
        color: #fff;
    }

    .sidebar .active {
        background-color: var(--secondary-color);
        color: #fff;
        font-weight: bold;
    }

    /* Content Area */
    .content {
        background-color: rgba(30, 30, 30, 0.8);
        padding: 20px 30px;
        border-radius: 10px;
        box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
        animation: fadeIn 1s ease-in-out;
    }

    @keyframes fadeIn {
        from { opacity: 0; }
        to { opacity: 1; }
    }

    .content h2, .content h3 {
        font-family: var(--header-font-family);
        color: var(--secondary-color);
        margin-bottom: 15px;
        animation: fadeInBold 1s ease-in-out;
    }

    @keyframes fadeInBold {
        from { font-weight: 300; }
        to { font-weight: 700; }
    }

    .content h2 {
        font-size: 2rem;
        margin-top: 20px;
    }

    .content h3 {
        font-size: 1.5rem;
        margin-top: 20px;
    }

    .content p {
        font-size: 1rem;
        margin-bottom: 15px;
    }

    .content ul {
        list-style: none;
        margin-bottom: 15px;
    }

    .content ul li {
        position: relative;
        padding-left: 20px;
        margin-bottom: 10px;
    }

    .content ul li::before {
        content: '•';
        position: absolute;
        left: 0;
        color: var(--accent-color);
    }

    pre {
        background-color: #2E2E2E;
        padding: 15px;
        border-radius: 5px;
        overflow-x: auto;
        margin-bottom: 15px;
        box-shadow: inset 0 0 10px rgba(0,0,0,0.5);
    }

    code {
        font-family: 'Courier New', Courier, monospace;
        color: #00FF00;
    }

    /* Images */
    .content img {
        width: 100%;
        max-width: 320px;
        border-radius: 10px;
        box-shadow: 0 4px 10px rgba(0,0,0,0.5);
        transition: transform 0.3s ease, box-shadow 0.3s ease;
        margin: 10px 0;
    }

    .content img:hover {
        transform: scale(1.05);
        box-shadow: 0 6px 15px rgba(0,0,0,0.7);
    }

    /* Separator */
    .separator {
        height: 2px;
        background: linear-gradient(to right, var(--secondary-color), var(--accent-color));
        margin: 30px 0;
        border: none;
        border-radius: 5px;
    }

    /* Reference Prompt */
    .reference {
        text-align: center;
        padding: 20px;
        background-color: rgba(30, 30, 30, 0.8);
        border-radius: 10px;
        font-size: 1.2rem;
        margin-top: 40px;
        box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    }

    /* Responsive Design */
    @media (max-width: 1200px) {
        .container {
            grid-template-columns: 1fr 2fr;
            padding: 100px 30px 30px 30px;
        }
    }

    @media (max-width: 992px) {
        .container {
            grid-template-columns: 1fr;
            padding: 100px 20px 20px 20px;
        }

        .sidebar {
            margin-bottom: 20px;
        }
    }

    @media (max-width: 768px) {
        .navbar {
            flex-direction: column;
            align-items: flex-start;
        }

        .navbar .login {
            margin-top: 10px;
        }
    }

    @media (max-width: 480px) {
        .content h2 {
            font-size: 1.5rem;
        }

        .content h3 {
            font-size: 1.2rem;
        }

        .content p, .content ul li {
            font-size: 0.9rem;
        }

        .navbar {
            padding: 10px 15px;
        }

        .navbar .logo {
            font-size: 1.2rem;
        }

        .navbar .login {
            padding: 6px 12px;
            font-size: 0.9rem;
        }
    }