body {
background-color: lightgray;
font-family: Arial, Helvetica, sans-serif;
}
#container {
width: 1100px;
margin: 0px auto;
border: 4px solid gray;
}
header {
background-color: red;
height: 100px;
width: 100%;
margin: 0px;
text-align: center;
line-height: 100px;
color: antiquewhite;
border-bottom: 2px solid black;
}
nav ul li {
float: left;
list-style: none;
margin: 20px;
line-height: 10px;
}
a {text-decoration:
none;}
ul {text-align: center; display: inline-block;}
#content{
float: left;
width: calc(80% - 20px);
background-color:green;
min-height: 500px;
padding: 10px;
}
.article {
color: white;
margin-top: 15px;
margin-bottom: 15px;
border-bottom: 1px solid white;
padding-bottom: 20px;
}
aside{
float: left;
width: calc(20% - 20px);
background-color:coral;
min-height: 500px;
padding: 10px;
}
footer {
background-color: black;
color: white;
text-align: center;
height: 30px;
line-height: 30px;
}
.clearfix{
clear:both;
}
 *{
margin: 0px;
padding: 0px;
}