.hero {
 background-size: cover;
 background-position: center;
}

body {
 font-family: Arial, sans-serif;
}

header nav ul {
 list-style: none;
}

header nav ul li a {
 text-decoration: none;
 color: inherit;
 transition: color 0.2s ease-in-out;
}

button {
 cursor: pointer;
 transition: background-color 0.2s ease-in-out;
}

footer {
 clear: both;
}