.article_heading {
  background: url(../images/OpticalRayTracer_32x32.png) no-repeat;
  padding-left:38px;
  padding-top:6px;
}

.data_field {
  width:120px;
  text-align:right;
  padding-right:2px;
}

.result_box {
  padding:10px;
  border:1px solid gray;
  background:#f0fff0;
  margin-left:3em;
}

.opticaldisp {
  border:1px solid gray;
}

button {
  margin:2px;
}

.bordered {
  padding:4px;
  border:1px solid gray;
}