Remove sidebar toggle when site is viewed on mobile

Hi I have this sidebar toggle for the widgets whenever my page is viewed on mobile. I want to remove it. I tried using media queries to hide it but it won’t work.
My page is http://www.airtixsale.com
I’m using the theme ‘Unicorn’ by wpblogs.
I’ve been searching for a solution but can’t find one. Thank you in advance for helping me out.