How can I make a clicked button transparent on my website?

Hey i was wondering does anyone know how to get rid of the grey area filled in the button when u click on it? I wanna get it so its transparent even when u click on it and the border just expans like i have rn!

thanks in advance!

web: scepticalclothing.com

pass: Drop2

@ScepticalClo ,

.btn:not([disabled]):hover, .shopify-payment-button .shopify-payment-button__button–unbranded:not([disabled]):hover, .btn:focus, .shopify-payment-button .shopify-payment-button__button–unbranded:focus {
background: none;
}

Add this css at the bottom of Online Store->Theme->Edit code->Assets->theme.scss.liquid

ay thanks bro! u the goat