#postthumb {
  width: 315px;
  height: 270px;
}

#postthumb #overlay {
  opacity: 0;
  position: absolute;
  top: 0;
  left: 0;
  width: 315px;
  height: 270px;
  text-align: center;
}

#postthumb #overlay:hover {
  position: absolute;
  opacity: .7;
  background-color:#FFF;
  transition: opacity 150ms ease-in-out 0s;
  width: 315px;
  height: 270px;
  margin: 0px;
}

#postthumb2 {
  position:relative;	
  width: 315px;
  height: 270px;
}

#postthumb2 #overlay2 {
  opacity: 0;
  position: absolute;
  top: 0;
  left: 0;
  width: 315px;
  height: 270px;
  text-align: center;
}

#postthumb2 #overlay2:hover {
  position: absolute;
  opacity: .7;
  background-color:#FFF;
  transition: opacity 150ms ease-in-out 0s;
  width: 315px;
  height: 270px;
  margin: 0px;
}

#postthumb3 {
  position:relative;
  width: 315px;
  height: 270px;
}

#postthumb3 #overlay3 {
  opacity: 0;
  position: absolute;
  top: 0;
  left: 0;
  width: 315px;
  height: 270px;
  text-align: center;
}

#postthumb3 #overlay3:hover {
  position: absolute;
  opacity: .7;
  background-color:#FFF;
  transition: opacity 150ms ease-in-out 0s;
  width: 315px;
  height: 270px;
  margin: 0px;
}