body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #111;
    color: #fff;
}
.sidebar {
    position: fixed;
    width: 180px;
    height: 100%;
    background: #000;
    padding: 20px 10px;
}
.sidebar ul {
    list-style: none;
    padding: 0;
}
.sidebar ul li {
    margin: 20px 0;
}
.sidebar ul li a {
    color: #ffb600;
    text-decoration: none;
    font-weight: bold;
}
.main {
    margin-left: 200px;
    padding: 20px;
}
.gallery-container {
    display: flex;
    flex-direction: column;
}
.category h2 {
    border-bottom: 1px solid #444;
    margin-top: 40px;
}
.category a {
    display: inline-block;
    margin: 5px;
}
.category img {
    max-height: 200px;
    border-radius: 10px;
    box-shadow: 0 0 10px #000;
}
footer {
    margin-top: 50px;
}