styles.css

* {
    box-sizing: border-box;
}
html, body, div, span, h1, h2, h3, h4, h5, h6, p, a, ul, li{
                 
    margin: 0;
    padding: 0;
    border: 0;
    font-size: 100%;
    vertical-align: baseline;
}
body {
    font-family: Verdana, Arial, sans-serif;    
    background-color: #f7f7f7;
}
#header{ 
    background-color: #f4f4f4;
}
#header h1 {
    font-size: 24px;
    text-transform: uppercase;
    font-weight: bold;
    padding: 30px 30px 30px 10px;
    clear: both;
}
#nav {
    background-color: #eee;
    border-top: 1px solid #ccc;
    border-bottom: 1px solid #ccc;
}
#nav li {
    float: left;
    list-style: none;   
}
#nav a {
    display: block;
    color: black;
    padding: 10px 25px;
    text-decoration: none;
    border-right: 1px solid #ccc;
}
#nav li:last-child a {
    border-right: none; 
}
#nav a:hover {
    font-weight: bold;
}
#nav:after {
    content: " ";
    display: table;
    clear: both;
}
.wrapper{
    background-color: #f7f7f7;
}
.aside h2 {
    font-size: 0.95em;
    margin-top: 15px;
}
.aside h3 {
    font-size: 0.85em;
    margin-top: 10px;
}
.aside p, .aside li {
    font-size: .75em;
    margin-top: 10px;   
}
.aside li{ 
    list-style-type: none;
}
#sidebar1 {
    float: left;
    width: 20%; 
    padding: 0 10px 0 20px;
}
#sidebar2 {
    float: right;
    width: 20%; 
    padding: 0 20px 0 10px;
}
#article{
    background-color: #fafafa;
    border-left: 1px solid #ccc;
    border-right: 1px solid #ccc;
    margin-left: 20%;
    margin-right: 20%;
    padding: 15px;
    width: 60%;
}
#article:after{
    clear:both;
    display:table;
    content:'';
}
#article h2{
    font-size: 1.3em;
    margin-bottom:15px;
}
#article p{
    line-height: 150%;
    margin-bottom: 15px;
}
#footer{ 
    border-top: 1px solid #ccc;
    font-size: .8em;    
    text-align: center;
    padding: 10px 10px 30px 10px;
}
#nav ul, #header h1, .wrapper, #footer p {
    max-width: 1200px;
    margin: 0 auto; 
}
.wrapper, #nav, #header, #footer{
    min-width: 768px;
}