.colum-3 {
  display: flex;
  justify-content: space-between;
  margin: 0px -15px;
}
.colum-3 .item {
  max-width: calc(100% - 500px);
  display: flex;
  justify-content: space-between;
  margin: 0 15px;
  height: 600px;
  line-height: 25px;
}
.colum-3 .item:last-child {
  width: 250px;
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
}
.colum-3 .item:first-child {
  width: 250px;
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
}