Image scaling issue for Mobile (Corey Henson Template)

I am using the Henson template and cannot figure out to to make my photos scale down to a reasonable size for the mobile version of my site. I've provided images of what it looks like below. My site is maxwalkerdesign.com

Add to Design > Custom CSS

@media screen and (max-width:640px) {
.tweak-index-slideshow-animation .collection-images .image-container img {
    width: 100% !important;
    height: auto !important;
    left: 0 !important;
    top: 30% !important;
}
}