.center-div
{
  position: absolute;
  margin: auto;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  width: 100px;
  height: 100px;
  background-color: rgb(245, 245, 245);
  opacity: 0.7;
  border-radius: 3px;
  text-align:center;
  vertical-align: middle;
  border: 1px  rgb(221, 221, 221) solid;
}