#header {
    position: absolute;
    top: 0px;
    left: 1em 
}

#interface {
    position: absolute;
    top: 8em;
    left: 1em;

    height: 70%;
    width: 75%
}
@media screen
{
  #interface div,canvas {
      border: 1px solid black;
      border-radius: 15px
  }
}
@media print
{
  #interface #menu, #testimonial {
    display: none
  }
}
#interface div div {
    border: none
}
#interface #menu {
    margin-bottom: 1em;
    height: 2em;
    width: 100%;
    background-color: green
}
#testimonial {
    float: right;
    width: 20%;
    margin-top: 11em;
    color: khaki;
    font-family: cursive
}
#testimonial .q {
    font-size: 700%;
    float: left;
    margin-top: -45px;
    margin-right: 15px;
    height: 80px;
}
#interface #io {
    float: left;

    height: 100%;
    width: 100%
}
#interface #io #input,#output {
    width: 100%;
    height: 49%
}