.nav li ul{width:350px!important}.nav li li ul{left:350px!important}#top-menu li li a{width:310px}#main-header .et_mobile_menu li ul.hide{display:none!important}#mobile_menu .menu-item-has-children{position:relative}#mobile_menu .menu-item-has-children>a{background:transparent}#mobile_menu .menu-item-has-children>a+span{position:absolute;right:0;top:0;padding:10px 20px;font-size:20px;font-weight:700;cursor:pointer;z-index:3}span.menu-closed:before{content:"\4c";display:block;color:#fff;font-size:16px;font-family:ETmodules}span.menu-closed.menu-open:before{content:"\4d"}Here’s the jQuery:Be sure to put this in the section in the integrations tab under Divi>Theme Options>Integrations.
Option 2 (WITH Theme Builder):Just add this to your theme customizer CSS area or ideally your child theme stylesheet. You can customize the color,size,etc to your liking. Again be sure to reference the ET icon guide (link below) if you want to change the icons.
#page-container .mobile_nav li ul.hide{display:none!important}#page-container .mobile_nav .menu-item-has-children{position:relative}#page-container .mobile_nav .menu-item-has-children>a{background:transparent}#page-container .mobile_nav .menu-item-has-children>a+span{position:absolute;right:0;top:0;padding:10px 20px;font-size:20px;font-weight:700;cursor:pointer;z-index:3}#page-container span.menu-closed:before{content:"\4c";display:block;color:#000;font-size:16px;font-family:ETmodules}#page-container span.menu-closed.menu-open:before{content:"\4d"}