html, body{
  background-color: #333;
  
  display: flex;
  align-items: center;
  justify-content: center;
  
  height: 100%;
  width: 100%;
  
}

.btn .fa{
  margin-right: 10px;
}

.fa-spinner{
  animation: rotateSpinner 3s infinite linear;
}

@keyframes rotateSpinner{
  to{transform: rotate(360deg);}
}

.btn{
  display: inline-block;

  border: 2px solid white;  
  
  padding: 2px;
  
  font-family: 'Futura', sans-serif;
  font-size: 13px;
  text-transform: uppercase;
  color: white;
  
  text-align: center;
  
  transition: all .4s ease-in-out;
  
  align-items: center;
  justify-content: center;
 
  overflow: hidden;
  
}

  .state{
      line-height: 3em;
      padding: 0 10px;
      width: 160px;
      background-color: #FF5D66;
  }

  .state--added{
    width: 120px;
    background-color: #49dd87;
  }

  .state--adding{
    width: 200px;
    background-color: #f99677;
  }

  .state--is-hidden{
    display: none;
    transform: scale(.1);
  }

  .state--is-active{
    animation: stateIn .3s ease;
  }

  @keyframes stateIn{
    from{
      transform: scale(.1);
      opacity: 0;
    }
  }