You can try the following code in Design > Custom Css
#block-yui_3_17_2_1_1632267362014_2993 {
padding-bottom: 0 ;
}
section[data-section-id="6147778640521c01c31c75d3"] #gridThumbs {
padding-top: 0;
}
Paste this into Design->Custom CSS
@media only screen and (max-width: 768px) {
#block-yui_3_17_2_1_1631862532703_91583 {
max-width: 100px;
margin: auto;
}
}