img {
    display: none;
    visibility: hidden;
    width:512px;
    height:512px;
}
input{
    display: none;
    visibility: hidden;
}
label {
    display: inline-block;
    padding: 0.3em;
    border: 1px solid #CCC;
    background-color: #EEE;
    border-radius: 4px;
    cursor: pointer;
}

label:hover {
    background-color: #BBB;   
}

input:checked + img {
    display: block;
    visibility: visible;
}
input:checked {
    display: none;
    visibility: hidden;
}