Background Image on Home Page & Footer to Fit on Mobile

Site URL: https://blackfoodtruckfestival.com/new-homepage

I created background artwork for the homepage and footer but it won't size properly on mobile. I check my phone as well. I've tried several of the codes listed in other posts, but nothing works. 

Can someone help?

URL: blackfoodtruckfestival.com/new-homepage

Password: Superduper60

Try adding to Design > Custom CSS

/* Mobile home top banner */
@media screen and (max-width:767px) {
[data-section-id="61df95b5f3dca65c26b44ef6"] {
    min-height: unset !important;
    height: 60vh;
}
[data-section-id="61df95b5f3dca65c26b44ef6"] h1 {
    font-size: 30px;
}
[data-section-id="61df95b5f3dca65c26b44ef6"] .columns-12 {
    position: relative;
    top: -50px;
}
}