.image {
    display: block;
    margin-left: auto;
    margin-right: auto;
    margin-top: 150px;
    width: 50%;
    position: sticky;
}

.XRF {
    font-family: sans-serif;
    border-width:5px;  
    border-style:solid;
    display: none;
    width: 140px;
    margin-top: -190px;
    margin-left: 165px;
}

.FORS {
    font-family: sans-serif;
    border-width:5px;  
    border-style:solid;
    display: none;
    width: 140px;
    margin-top: -125px;
    margin-left: 165px;
}

.sidenav {
    height: 100%;
    width: 0px;
    position: fixed;
    z-index: 1;
    /*top: 0;*/
    left: 0;
    background-color: #212529;
    overflow-x: hidden;
    padding-top: 20px;
    transition: 0.5s;
}

.sidenav a {
    padding: 6px 6px 6px 32px;
    text-decoration: none;
    font-size: 25px;
    color: #818181;
    display: block;

}

.sidenav a:hover {
    color: #f1f1f1;
}

.sidenav .closebtn {
    position: absolute;
    top: 0;
    right: 25px;
    font-size: 36px;
    margin-left: 50px;
}

.main {
    margin-left: 200px; /* Same as the width of the sidenav */
}

@media screen and (max-height: 450px) {
  .sidenav {padding-top: 15px;}
  .sidenav a {font-size: 18px;}
}