Hello,
1) Please change the previous code to:
.ls-layers, .ls-inner {
z-index: auto !important;
}
2) The problem is caused by styles of layerslider https://prnt.sc/puwddy https://prnt.sc/puwdg1
Your slider on the home page has only 1 slide, so you can try to recreate this block using default elements of WPBakery Page Builder, and delete the slider.
Regards