Resize Image for Mobile Site

Site URL: https://www.evolvehumanperformance.net/21day-nutrition-challenge-females

Trying to resize images on mobile site 

I've tried using other snippets of code people are suggesting but it doesn't seem to be working. 

Trying to resize all of the blue icons on this page: https://www.evolvehumanperformance.net/21day-nutrition-challenge-females

Thanks in advance

Add to Home > Design > Custom CSS

/* resize icons */
@media screen and (max-width:767px) {
/* envolve online */
div#block-7fe2922703671f73b889 + .row .image-block {
    width: 50%;
    margin: 0 auto;
}
/* our program */
div#block-d8d2d153673ebb10d2f4 + .row .image-block {
    width: 50%;
    margin: 0 auto;
}
}