Untitled

button.darkmode-toggle img {
    position: absolute;
    left: 9px;
    right: auto;
    z-index: 1;
    display: none !important;
    visibility: none !important;
}

.darkmode--activated button.darkmode-toggle img {
    left: auto;
    right: 9px;
}

button.darkmode-toggle::after {
    content: '';
    display: inline-block;
    background: #fff;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    position: absolute;
    left: 8px;
    right: auto;
    border: 2px solid #000;
}

.darkmode--activated button.darkmode-toggle::after {
    left: auto;
    right: 8px;
    filter: invert(1);
}