.btn {
  text-align: center;
  padding: 100px 20px;
}

.btn a {
  display: inline-block;
  width: 150px;
  height: 150px;
  position: relative;
}

.btn a::before, .btn a::after {
  content: "";
  display: block;
  -webkit-transition: 0.3s;
  transition: 0.3s;
  border-radius: 100%;
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  margin: auto;
}

.btn a::before {
  width: 65%;
  height: 65%;
  border: solid 2px #000;
}

.btn a::after {
  content: "";
  display: block;
  width: 0%;
  height: 0%;
  background: #000;
  border-radius: 100%;
  mix-blend-mode: difference;
}

.btn a img {
  position: absolute;
  top: 0;
  left: 0;
  mix-blend-mode: difference;
  right: 0;
  bottom: 0;
  margin: auto;
  -webkit-transition: 0.3s;
  transition: 0.3s;
  width: 100%;
  height: 100%;
  -webkit-animation: btn 15s infinite linear;
          animation: btn 15s infinite linear;
}

@-webkit-keyframes btn {
  0% {
    -webkit-transform: rotate(0);
            transform: rotate(0);
  }
  100% {
    -webkit-transform: rotate(360deg);
            transform: rotate(360deg);
  }
}

@keyframes btn {
  0% {
    -webkit-transform: rotate(0);
            transform: rotate(0);
  }
  100% {
    -webkit-transform: rotate(360deg);
            transform: rotate(360deg);
  }
}

.btn a svg {
  width: 40%;
  height: 40%;
  position: absolute;
  top: 0;
  left: 0;
  mix-blend-mode: difference;
  stroke-width: 4;
  right: 0;
  fill: none;
  bottom: 0;
  margin: auto;
  -webkit-transition: 0.3s;
  transition: 0.3s;
  stroke: #000;
}

.btn a:hover img {
  width: 80%;
  height: 80%;
  -webkit-animation-duration: 100s;
          animation-duration: 100s;
  animation-direction: reverse;
}

.btn a:hover svg {
  stroke: #fff;
  stroke-width: 6;
  width: 25%;
}

.btn a:hover::before {
  width: 90%;
  height: 90%;
  -webkit-animation: bg_1 0.3s linear;
          animation: bg_1 0.3s linear;
}

@-webkit-keyframes bg_1 {
  0% {
    width: 65%;
    height: 65%;
  }
  70% {
    width: 100%;
    height: 100%;
  }
  100% {
    width: 90%;
    height: 90%;
  }
}

@keyframes bg_1 {
  0% {
    width: 65%;
    height: 65%;
  }
  70% {
    width: 100%;
    height: 100%;
  }
  100% {
    width: 90%;
    height: 90%;
  }
}

.btn a:hover::after {
  width: 50%;
  height: 50%;
  -webkit-animation: bg_2 0.2s linear;
          animation: bg_2 0.2s linear;
}

@-webkit-keyframes bg_2 {
  0% {
    width: 0%;
    height: 0%;
  }
  100% {
    width: 50%;
    height: 50%;
  }
}

@keyframes bg_2 {
  0% {
    width: 0%;
    height: 0%;
  }
  100% {
    width: 50%;
    height: 50%;
  }
}
/*# sourceMappingURL=style.css.map */