change image for mobile

Site URL: https://cheetah-krill-7gh3.squarespace.com/config/

Hi I am wanting to change this image to a different one for mobile. 

Thanks in advance!

site wide password: donuts

can't see your site because it's not published but broadly speaking add the two images you want in different sections on your page. find the two section IDs and then add css to turn them on or off depending on whether or not its viewed in mobile. 

 similar to the css in this post

section[data-section-id="6108bec0e3a3c73804194bf7"] {
    display:block;
}
section[data-section-id="61258a40711e8b5459fb0271"] {
    display:none;
}

@media screen and (max-width: 768px) {
    section[data-section-id="6108bec0e3a3c73804194bf7"] {
        display:none;
    }
    section[data-section-id="61258a40711e8b5459fb0271"] {
        display:block;
    }
}

to find your section ids, use the squarespace id finder chrome section or inspect the source of your website.