Help changing Theme width

Hello Im having trouble changing my theme width. The webpage is http://beatzgofed.com/beat-store/

I need a full page so the music player can stretch to the right

he player should look like the player here http://legionbeats.com/

[please continue with your original topic at https://wordpress.org/support/topic/how-to-change-theme-width-5?replies=6 ]