#links div {
  float: left;
  width: 90px;  /* adjust to desired width */
  height: 50px; /* adjust to desired height */
  text-align: center;
  padding: 0;
  margin: 0 5px;  /* adjust as desired */
}
#links div img {
  border: none;
  padding:10px;
  vertical-align: middle;
}