Button Size

Site URL: https://www.mattportch.com/contact

Hi,

Clearly Squarespace have messed with the settings again which has ruined some of my CSS code.

Can anyone tell me how to resize my SEND button on my contact page?

https://www.mattportch.com/contact

It's gone really small and want it roughly same as my Add to Cart button:

https://www.mattportch.com/lost-america-prints/p/the-wall-frame-arizona

Also, just out of interest, what is the quickest way to search for this in my Custom CSS?

Add to Design > Custom CSS

/* Form block button */
input.button.sqs-system-button {
    padding: 1em !important;
    font-size: 0.8em !important;
}

Thanks!