How to remove highlighted area around menu box on mobile

[undercoverfresh]

I'm looking to remove the highlighted gray box when it appear as you press the menu tab on mobile 

(it happens for a split second)

url knmb1c-pf.myshopify.com

password samurai 

 

[Small_Task_Help]

Hi,

Scroll to the bottom of CSS file and add this code

CSS code example

button:focus, button:active,
a:focus, a:active {
    outline: none !important;
    box-shadow: none !important;
    background: transparent !important;
}