Hi Tim
Thanks for contacting us.
Okay, Kindly add the below CSS in the Additional CSS box, Please go to the Appearance => Customize => Additional CSS then paste the CSS here and click to publish button.
.box-icon-image img {
-webkit-filter: grayscale(200%) brightness(200%) contrast(200%);
filter: grayscale(200%) brightness(200%) contrast(200%);
}
.box-icon-image:hover img {
-webkit-filter: none;
filter: none;
}
Let us know if it works.
Thanks