.installer {
  width: 200px;
  height: 40px;
}

.installer label {
  position: absolute;
  height: 40px;
  width: 200px;
  border-radius: 5px;
  overflow: hidden;
  cursor: pointer;
}

.installer label input {
  display: none;
}

.installer label span {
  position: absolute;
  height: 40px;
  width: 200px;
  line-height: 40px;
  text-align: center;
  color: #fff;
  background: #3F8EFC;
  border-radius: 5px;
}

.installer label input:checked ~ span {
  background: #87E544;
  animation: downloadSuccess 3.1s ease;
}

.installer label span:after {
  content: 'DOWNLOAD';
  position: absolute;
  width: 80%;
  height: 100%;
  left: 10%;
}

.installer label input:checked ~ span:after {
  content: 'Thank you!';
  animation: downloadState 3s;
}

.installer label span:before {
  content: '';
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0px;
  left: 0px;
  opacity: 0;
  background: rgba(255,255,255,.2);
}

.installer label input:checked ~ span:before {
  animation: downloadProgress 3s cubic-bezier(.67,.13,.1,.81);
}

@keyframes downloadSuccess {
  0%, 90% {
    background: #3F8EFC;
  }

  100% {
    background: #87E544;
  }
}

@keyframes downloadState {
  0%, 95% {
    content: 'DOWNLOADING...'
  }

  100% {
    content: 'Thank you for download!'
  }
}

@keyframes downloadProgress {
  0% {
    width: 5%;
    opacity: 1;
  }

  35% {
    width: 17%;
  }

  64% {
    width: 51%;
  }

  81% {
    width: 70%;
  }

  90% {
    width: 86%;
    opacity: 1;
  }

  100% {
    width: 100%;
    opacity: 0;
  }
}