.btn-circle {
    width: 45px;
    height: 45px;
    line-height: 45px; 
    text-align: center;
    padding: 0;
    border-radius: 50%;
    color: whitesmoke;
    background-color: black;
  }
  .btn-circle:hover, .sec:hover, .btn-circle:focus{
    background-color: black;
    color: goldenrod;
  }

  .sec{
    border-radius: 20%;
  }