/* The Overlay (background) */
.overlay {
  /* Height & width depends on how you want to reveal the overlay (see JS below) */   
  height: 100%;
  width: 100%;
  display:block;
  position: fixed; /* Stay in place */
  z-index: 111111; /* Sit on top */
  left: 0;
  top: 0;
  background-color: rgb(0,0,0); /* Black fallback color */
  background-color: rgba(0,0,0, 0.8); /* Black w/opacity */
  overflow-x: hidden; /* Disable horizontal scroll */
  transition: 0.5s; /* 0.5 second transition effect to slide in or slide down the overlay (height or width, depending on reveal) */
}

.spinner-border {
  display: block;
  position: fixed;
  z-index: 1031;
  top: 50%;
  right: 50%; /* or: left: 50%; */
  margin-top: -..px; /* have of the elements height */
  margin-right: -..px; /* have of the elements widht */
}