base.css

/* apply a natural box layout model to all elements */
*, *:before, *:after {
    -moz-box-sizing: border-box; 
    -webkit-box-sizing: border-box; 
    box-sizing: border-box;
}

html, body {
    height: 100%;
    font-family: "Helvetica Neue",Helvetica,Arial,sans-serif;
}

body {
    background-color: #fafafa;
    padding: 20px 20px 50px 140px;
}

nav {
    position: fixed;
    top: 20px;
    left: 20px;
}

nav > a {
    height: 100px;
    width: 100px;
    border-radius: 5px;
    display: block;
    margin-bottom: 20px;
    display: flex;
    text-align: center;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 500;
    font-size: 16pt;
    text-decoration: none;
    background-size: cover;
}

/*css for individual sections*/
#home .img {
    height: 400px;
    width: 600px;
    background-size: cover;
    border-radius: 5px;
}