remove shadow from submit button?

There is some kind of box shadow on the submit button that I cant’ seem to get rid of. Could you please help? Here’s the CSS I tried, that isn’t working:

.mc4wp-form input[type=”submit”] {
box-shadow: none !important;
-webkit-box-shadow: none !important;
-moz-box-shadow: none !important;
}

Thanks!
–Amelia
Oh, yes — a link to the site:
https://192.185.83.158/~artsmali/

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