<div id="contentback"><div id="content"></div></div>
#contentback{
position: absolute;
background: #0065FF;
opacity: 0.7;
margin: 10% 25% 20% 25%;
height:50%;
width:50%;
border-radius: 10px;
}
#content{
position: absolute;
opacity: 1;
margin: 0px;
height:100%;
width:100%;
border-radius: 10px;
}