Overlay problem with megamenu and slider about classic-rocket

theme.css
from:

.slick-arrow{position:absolute;top:0;height:100%;display:flex;flex-direction:column;justify-content:center;padding-top:0;padding-bottom:0;z-index:2}

to:

.slick-arrow{position:absolute;top:0;height:100%;display:flex;flex-direction:column;justify-content:center;padding-top:0;padding-bottom:0;z-index:1}

[MortenKL]

That'll do it - thanks a lot!, fixed in the minified css.
But It should probably be fixed in /css/components/slick-theme.scss - along the way.
Leaving it open for now.