Mobile – Custom Nav Sub Menu Background & Text Colors

Environment:
WordPress 4.9.4 with TwentySeventeen vs 1.4 Inactive | Genesis 2.5.3 | Epik Theme 1.5 Active

Hi Wes,
I’m hoping you can help me. I have the following custom code in a custom CSS file – so I can quickly and easily delete my code and revert to your “good” code if I mess things up. Not sure how to apply the same customizations to mobile screens too.

I may have given more code than you need to see but figure better that than not enough.

/*-------------------------------------------*/
/*DL Changes Header Background Color to White*/
/*-------------------------------------------*/

.front-page .site-header {
	background-color: #ffffff;
	}

/*-------------------------------------------*/
/*DL Nav Menu BG*/
/*-------------------------------------------*/

.genesis-nav-menu .sub-menu a:hover, .genesis-nav-menu .sub-menu li.current-menu-item > a, button, input[type="button"], input[type="reset"], input[type="submit"], .archive-pagination li a:hover, .archive-pagination .active a, .button, .widget .button, .front-page-2 .image-section, .portfolio .more-link, .site-header, .front-page-2, .front-page-5, .footer-widgets, .plan .popular {
    background-color: #fff;
}

.nav-primary .genesis-nav-menu a:focus, .nav-primary .genesis-nav-menu a:hover {
    color: #2e382f;
}

.genesis-nav-menu a {
    color: #73262b;
}

.genesis-nav-menu .menu-item {
    display: inline-block;
    text-align: left;
    background-color: #fff;
}

/*-------------------------------------------*/
/*DL Nav Menu List Items*/
/*-------------------------------------------*/
.nav-primary .genesis-nav-menu a:focus, .nav-primary .genesis-nav-menu a:hover {
    color: #2e382f;
}

.flexible-widgets {
    padding: 0px 0 3px;
}

/*-------------------------------------------*/
/*DL Nav Sub-Menu*/
/*-------------------------------------------*/

.genesis-nav-menu .sub-menu a {
    color: #ffffff;
    background-color: #73262b;
}

.nav-primary .genesis-nav-menu .sub-menu a:focus, .nav-primary .genesis-nav-menu .sub-menu a:hover {
    color: #2e382f;
    background-color: #b6ceb6;
}