.loader {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  position: relative;
  animation: rotate 1s linear infinite;
  display: block;
}
.loader::before {
  content: "";
  box-sizing: border-box;
  position: absolute;
  inset: 0px;
  border-radius: 50%;
  border: 6px solid #177991;
  animation: prixClipFix 2s linear infinite ;
}

@keyframes rotate {
  100%   {transform: rotate(360deg)}
}

@keyframes prixClipFix {
	0%   {clip-path:polygon(50% 50%,0 0,0 0,0 0,0 0,0 0)}
	25%  {clip-path:polygon(50% 50%,0 0,100% 0,100% 0,100% 0,100% 0)}
	50%  {clip-path:polygon(50% 50%,0 0,100% 0,100% 100%,100% 100%,100% 100%)}
	75%  {clip-path:polygon(50% 50%,0 0,100% 0,100% 100%,0 100%,0 100%)}
	100% {clip-path:polygon(50% 50%,0 0,100% 0,100% 100%,0 100%,0 0)}
}