SaS/web_dev/index.css

html {
    background-color: white;
}

h1 {
    padding-top: 50px;
    font-family: Palatino, serif;
    font-size: 32px;
    text-align: center;
}

ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
    overflow: hidden;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    border: 2px solid #e7e7e7;
    background-color: #f3f3f3;
}

li {
    float: left;
}

li a {
    display: block;
    border-top-right-radius: 5px;
    border-top-left-radius: 2.5px;
    color: #666;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
}

.active {
    background-color: olivedrab;
    color: white;
}

li a:hover:not(.active) {
    background-color: #e7e7e7;
}