add zindex on base theme docs
add zindex on base theme docs

mining/mining,avelino/mining,avelino/mining,AndrzejR/mining,jgabriellima/mining,chrisdamba/mining,seagoat/mining,AndrzejR/mining,seagoat/mining,jgabriellima/mining,mlgruby/mining,mlgruby/mining,mlgruby/mining,mining/mining,chrisdamba/mining