body, html {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: #FFFFFF;
    background: linear-gradient(135deg, #1E2D50, #2C3E50);
    overflow-x: hidden;
}

header {
    position: relative;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    background: url("https://images.gptkong.com/demo/sample1.png") no-repeat center center/cover, linear-gradient(135deg, #1E2D50, #2C3E50);
}

header h1 {
    font-size: 3rem;
    font-family: 'Open Sans', sans-serif;
    font-weight: bold;
    color: #FFFFFF;
    text-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    animation: fadeIn 2s ease-in-out;
}

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

.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: 200px;
    height: 100%;
    background: linear-gradient(180deg, #1A294A, #2C3E50);
    box-shadow: 2px 0 6px rgba(0, 0, 0, 0.2);
    z-index: 1000;
    transition: transform 0.3s ease;
}

.sidebar.hidden {
    transform: translateX(-200px);
}

.sidebar ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.sidebar ul li {
    margin: 20px 0;
    text-align: center;
}

.sidebar ul li a {
    text-decoration: none;
    color: #FFC600;
    font-size: 1.2rem;
    transition: color 0.3s ease;
}

.sidebar ul li a:hover {
    color: #00FFB8;
}

.content {
    margin-left: 220px;
    padding: 20px;
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
}

@media (max-width: 768px) {
    .sidebar {
        position: static;
        width: 100%;
        height: auto;
        display: flex;
        justify-content: center;
        box-shadow: none;
    }

    .content {
        margin-left: 0;
    }
}

h2, h3, h4 {
    font-family: 'Open Sans', sans-serif;
    font-weight: bold;
    margin-top: 30px;
}

pre {
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 5px;
    padding: 15px;
    overflow-x: auto;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.4;
}

code {
    color: #FFC600;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

table th, table td {
    border: 1px solid #FFC600;
    padding: 10px;
    text-align: left;
}

table th {
    background-color: rgba(255, 255, 255, 0.1);
}

.button {
    background-color: #007BFF;
    color: #fff;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.button:hover {
    background-color: #0056b3;
    transform: scale(1.1);
}

.image-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 10px;
    margin: 20px 0;
}

.image-gallery img {
    width: 100%;
    height: auto;
    border-radius: 5px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease;
}

.image-gallery img:hover {
    transform: scale(1.05);
}

footer {
    text-align: center;
    padding: 20px;
    background: linear-gradient(135deg, #2C3E50, #1E2D50);
    color: #FFC600;
    font-size: 0.9rem;
}