#def
{
background:#f0f8ff;
padding:5px;
border:1px solid blue;
width:700px;
margin:auto;
}
#diff_Q
{
background:#ffe4e1;
padding:5px;
border:1px solid red;
width:80px;
position:relative;
left:300px;
}
#over
{
position:relative;
top:-10px;
right:-3px;
}
#den
{
background:none;
position:relative;
left:-35px;
}
#def_deri
{
position:relative;
left:200px;
top:-10px;
}