.footer {
  position: relative; /* Ensure the pseudo-element is positioned relative to the footer */
  background-image: url(../images/dexter-black.jpg);
  background-position: center;
  background-size: cover;
  z-index: 1; /* Ensure content inside the footer is above the overlay */
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(117, 117, 117, 0.421); 
  z-index: -1;  
}