#btn-center {
    border-radius: 50%;
    background-color: #f8f8f8;
    box-shadow: 2px 2px 8px #888888;
    z-index: 10;

    width: 4em;
    height: 4em;

    position: absolute;
    left: 27vw;
    bottom: 3em;

    text-align: center;
}
#btn-center img{
    
    width:3em;
    height:3em;
    margin-top: 8px;
}

#btn-center:hover {
    cursor: pointer;
}

#btn-center h1 {
    background-color: black;
    border-radius: 50%;
    color: black;
    width: 0.8em;
    height: 0.8em;
    margin-left: 0.2em;
    margin-top: 0.2em;

}

@media screen and (max-width:1100px) {
    #btn-center {
      left: 27vw;
    }
}

@media screen and (max-width:900px) {
    #btn-center {
        left: 6.4vw;
      }
    #main.active #btn-center {
        left: 20%;
    }
  }