In the v1.4 theme update UberMenu Lite was updated from v2 to v3 and a great deal changed, which means that any navigation menu styling tips posted in this forum before January 1st, 2015 will most likely not work.
In UberMenu Lite v3, to set the colour of the hamburger icon you can use this custom CSS…
#MainNav .ubermenu-responsive-toggle { color: Fuchsia }
Go to Appearance > Theme Options > Custom CSS and add that CSS to your Custom CSS box, or add it to your custom stylesheet. Adjust the colour to suit your specific situation.
The toggle content text (the word “Menu”) can be removed or changed on the Appearance > UberMenu > Main UberMenu Configuration > Responsive & Mobile settings page, it’s the input box labelled Responsive Toggle Content.
If you want the colour of the hamburger icon to be different from the colour of the toggle content text you can do that with some more custom CSS…
#MainNav .ubermenu-responsive-toggle .fa { color: SpringGreen }