Both EasyMegaMenu and collapsed original menu is visible on tablets and phones

I'm using Joomla template "protostar" together with EasyMegaMenu and to have it work on small screens I have added the following to the template css:
@media (max-width: 979px){
.navbar.pull-left{
display:none;
}
.nav-collapse {
overflow: visible!important;
height: auto!important;
z-index: 100!important;
}
}
On small screens it looks like both the original collapsed menu and the easy mega menu is visible. How do I get rid of the original collapsed menu?
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