[Hueman] Hide submenu-items on mobile

Is it possible to hide submenu-items on the mobile menu, so users can choose which submenu to expand? I read somewhere to add the following css to the style, but that will set the max height to the initial visible items.

@media only screen and (max-width: 719px) {
	.nav ul {
		display: none !important;
	}

	.nav li:hover ul {
		display: block !important;
	}

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