body{
    text-align: center;
}
.btn{
    height:100px;
    width: 100px;
    border-radius: 20%;
    border: 10px solid black;
    margin: 2.5rem;
}

.btn-container{
    display: flex;
    justify-content: center;

}

.yellow{
    background-color: #f89a42;
}
.red{
    background-color: #ef5b88;
}

.purple{
    background-color:#819ff9;
}

.green{
    background-color:#00b615;
}

.flash{
    background-color: white;
}

.userclick{
    background-color:green;
}

.switch {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
  }
  
  /* Hide default HTML checkbox */
  .switch input {
    opacity: 0;
    width: 0;
    height: 0;
  }
  
  /* The slider */
  .slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    -webkit-transition: .4s;
    transition: .4s;
  }
  
  .slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    -webkit-transition: .4s;
    transition: .4s;
  }
  
  input:checked + .slider {
    background-color: #2196F3;
  }
  
  input:focus + .slider {
    box-shadow: 0 0 1px #2196F3;
  }
  
  input:checked + .slider:before {
    -webkit-transform: translateX(26px);
    -ms-transform: translateX(26px);
    transform: translateX(26px);
  }
  
  /* Rounded sliders */
  .slider.round {
    border-radius: 34px;
  }
  
  .slider.round:before {
    border-radius: 50%;
  }


  .x{
    border-radius: 20%;
    border: 10px solid white;
  }

  .dark{
    position: absolute;
    top: 0;
    right: 0;
    margin: 20px 20px;
  }

  .love{
    font-size: 20px;
  }

  .bheart{
    color: red;
  }

  #start{
    height: 30px;
    width: 60px;
    border-radius: 10%;
  }