*{
margin:0;
padding:0;
}

body{
background :#e6e6e6;
}

header, .main, footer{
width:90%;
max-width:1000px;
margin:20px auto;
}

header nav{
background:#528FD5;
overflow:hidden;
}

header nav ul{
list-style:none;
}

header nav ul li{
float:left;
}

header nav ul li a{
padding:10px 20px;
display:block;
color:#fff;
text-decoration:none;

}
header nav ul li a:hover{
background:#75ACEC;
text-decoration:underline;
}
}
header nav ul li a:active{
background:black;
}

.main .articles {
width:68.5%;
margin-right:1.5;
float:left;
text-align:justify;
}

.main .articles article {
padding: 20px;
background:#fff;
margin-bottom:20px;
text-align:justify;
}

aside{
width:30%;
margin-left:1.3%;
background:#ff4500;
float:left;
padding:20px;
box-sizing:border-box;
text-align:justify;
} 

#dos {
background:RGB;
text-align:justify;
padding:20px;
}
 footer{
 background:green;
 clear:both;
 text-align:center;
 padding-top:10px;
 color:white;
 }
 #uno
 {
 padding:10px 20px;
text-align:center;
background:#528FD5;
 }
 #uno img
 {border-radius:15px;
 box-shadow: 5px 5px 0px #ccc;
 }
#dos
{

position:relative;
top:5px;
bottom:;
right:;
left:;
}