.corner_zoom a::before {
  content: "";
  position: absolute;

  height: 20%;
  width: 10%;

  left: 50%;
  bottom: 50%;

  border-left: 2px solid #fff;
  border-bottom: 2px solid #fff;

  transform: scaleX(0) scaleY(0);
  opacity: 0;
  transition: all 0.5s;
}

.corner_zoom a::after {
  content: "";
  position: absolute;
  
  height: 20%;
  width: 10%;
  
  right: 50%;
  top: 50%;
  
  border-right: 2px solid #fff;
  border-top: 2px solid #fff;
  
  transform: scaleX(0) scaleY(0);
  opacity: 0;
  transition: all 0.5s;
}

.corner_zoom a:hover::before{
  left: 0;
  bottom: 10%;
  transform: scaleX(2) scaleY(1.2);
  opacity: 1;
}
.corner_zoom a:hover::after {
  right: 0;
  top: 10%;
  transform: scaleX(2) scaleY(1.2);
  opacity: 1;
}