html, body{
    font-family: Helvetica;
}
header{
    float: left;
    width: 70%;
    height: 400px;
    background-color: snow;
    text-align: center;
}
main{
    float:left;
    width: 70%;
    height: 400px;
    background-color: snow;
    font-size: 150%;
}
section{
    float:right;
    width: 30%;
    height: 150px;
    background-color: steelblue;
    color: white;
    text-align: center;
}
nav{
    float:right;
    width: 30%;
    height: 350px;
    background-color: steelblue;
    color: white;
}
aside{
    float:right;
    width: 30%;
    height: 300px;
    background-color: snow;
    text-align: center;
}
footer{
    clear:both;
    background-color: steelblue;
    color: white;
}
h2{
    font-size: 250%;
}
img{
    padding: 4px;
}
img:hover{
    padding: 3px;
    border: solid 1px steelblue;
}