input.symptom-btn {
    display: none;
}

div.symptom-btn {
    cursor: pointer;
    width: 170px;
    height: 170px;
    border-radius: 100px;
    background: #6c757d;
    position: relative;
    text-align: center;
    display: inline-block;
    text-align: center;
    margin: 10px;
    vertical-align: middle;
}

input.symptom-btn + label {
    cursor: pointer;
    width: 170px;
    height: 170px;
    border-radius: 100px;
    background: #6c757d;
    position: relative;
    text-align: center;
    vertical-align: middle;
    color: #ffffff;
    font-family: arial, sans-serif;
    font-size: 22px;
    padding-left: 10px;
    padding-right: 10px;
}

.symptom-btn label {
    display: table-cell; 
    vertical-align: middle; 
    text-align: center;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

@media (hover: hover) and (pointer: fine) {
    input.symptom-btn:not(:checked) + label:hover {
        background: rgba(130, 26, 94, 0.65);
    }
}

input.symptom-btn + label:active,
input.symptom-btn:checked + label {
    background: #821a5e;
    border-color: #6c757d;
    border-style: solid;
    border-width: 2px;
}