Make scolor white from black on GameNow theme?

So, I am using the Gamenow theme and I want to know how I can set the gamenows default color scheme from Dark to Light… Like when the page loads up I want it to be light and not dark….

this is the theme … https://www.wpnow.com/demo/gamenow/

The demo is in white but it has an option to change it to black on click as well..I want my one to be White as default when someone visits…