body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #f0f0f0;
}
.container {
    text-align: center;
}
h1 {
    color: #333;
}
p {
    color: #666;
}
/* place header at the top of the page */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: #333;
    color: #fff;
    padding: 10px 0;
    text-align: center;
}
/* align all links in header in one row */
header a {
    color: #fff;
    text-decoration: none;
    padding: 10px;
}
header a:hover {
    background-color: #555;
}

/* make list of links */
nav ul {
    list-style-type: none;
    margin-top: 20px;
    padding: 0;
}
nav ul li {
    display: inline;
    vertical-align: top;
}
/* set image size in nav */
nav img {
    width: 30px;
    height: 30px;
}
/* place footer at the bottom of the page */
footer {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    background-color: #333;
    color: #fff;
    padding: 10px 0;
    text-align: center;
}