.spinner {
  display: inline-block;
  position: relative;
}

.spinner > div {
  -webkit-animation: spinner_anim 1.2s linear infinite;
  -moz-animation: spinner_anim 1.2s linear infinite;
  animation: spinner_anim 1.2s linear infinite;
  border-radius: 5px;
  background-color: var(--text-color);
  position: absolute;
  width: 20%;
  height: 7.8%;
  top: 46.1%;
  left: 40%;
}

@keyframes spinner_anim {
 0% { opacity: 1; }
 100% { opacity: 0.15; }
}

@-moz-keyframes spinner_anim {
 0% { opacity: 1; }
 100% { opacity: 0.15; }
}

@-webkit-keyframes spinner_anim {
 0% { opacity: 1; }
 100% { opacity: 0.15; }
}