.slider_wrapper {
  position: relative;
}

.custom-prev,
.custom-next {
  position: absolute;
  top: 50%;  
  transform: translateY(-50%);
  z-index: 20;

  background: white;
  color: grey;

  width: 30px;    

  display: flex; 
  align-items: center; 
  justify-content: center;

  border-radius: 50%;
  cursor: pointer;
}

.custom-prev {
  left: -20px;
  width: 20px ;
  height: 20px ;
}

.custom-next {
  right: -20px;
   width: 20px ;
  height: 20px ;
}