body {
    font-family: Arial;
    margin: 0;
    background: #f5f5f5;
}

header {
    background: #0077cc;
    color: white;
    text-align: center;
    padding: 20px;
}

nav {
    background: #333;
}

nav ul {
    list-style: none;
    display: flex;
    margin: 0;
    padding: 0;
}

nav ul li {
    padding: 15px;
}

nav ul li a {
    color: white;
    text-decoration: none;
}

main {
    width: 70%;
    float: left;
    padding: 20px;
}

section {
    background: white;
    padding: 20px;
    margin-bottom: 20px;
    border-radius: 8px;
}

aside {
    width: 22%;
    float: right;
    margin: 20px;
    padding: 20px;
    background: white;
    border-radius: 8px;
}

footer {
    clear: both;
    background: #222;
    color: white;
    text-align: center;
    padding: 15px;
}

button {
    padding: 10px;
    background: #0077cc;
    color: white;
    border: none;
    cursor: pointer;
}

button:hover {
    background: #005fa3;
}

input {
    padding: 10px;
    width: 250px;
}

div {
    margin-top: 15px;
    padding: 10px;
    background: #eef;
}