.center {
  display: block;
  height: 100%;
  width: 100%;
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  -khtml-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}

.container {
	position: relative;
  overflow: hidden;
  margin: auto;
  width: 4rem;
  height: 4rem;
}



.btn {
  padding: 0;
  border-radius: 100%;
  width: 40px;
  height: 40px;
  font-size: 3em;
  color: #fff;
  padding: 0;
  margin: 0;

	position: relative;
	z-index: 999;
  display: inline-block;
    line-height: 40px;
    text-align: center;
    white-space: nowrap;
    vertical-align: middle;
    -ms-touch-action: manipulation;
    touch-action: manipulation;
    cursor: pointer;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    background-image: none;
}

.pulseRing {
  content: '';
  width: 40px;
  height: 40px;
  border-radius: 50%;
  position: absolute;
  top: -1px;
  left: -1px;
  animation: pulsate infinite 1.5s;
}



@-webkit-keyframes pulsate {
  0% {
    -webkit-transform: scale(1, 1);
    opacity: 1;
  }
  100% {
    -webkit-transform: scale(1.3, 1.3);
    opacity: 0;
  }
}

.loader {
  content: '';
  width: 45px;
  height: 45px;
  border-radius: 100%;
  display: inline-block;
  position: absolute;
  border: 3px solid;
  border-color: #FFF #FFF transparent transparent;
  box-sizing: border-box;
  animation: rotation 1s linear infinite;
}
.loader::after,
.loader::before {
  content: '';  
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  margin: auto;
  border: 3px solid;
  width: 40px;
  height: 40px;
  border-radius: 100%;
  animation: rotationBack 0.5s linear infinite;
  transform-origin: center center;
}
.loader::before {
  content: '';
  width: 40px;
  height: 40px;
  border-color: #FFF #FFF transparent transparent;
  animation: rotation 1.5s linear infinite;
}
    
@keyframes rotation {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
} 
@keyframes rotationBack {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(-360deg);
  }
}