Can I change my submit button?

I just put an order form together for a line of stationery that I'm selling wholesale. I used a theme and was able to customize more of the theme (so great!), but I can't seem to change the submit button. The submit button is very cool, it the color is wrong though and I don't seem to be able to change that. Perhaps it's an image, but I can't seem to delete the image either. I'd be fine with a really basic submit button in one of my store's colors. Can you help?

Yes, the button used on that theme uses an image, this is maybe why you cannot find it. 

However, the button can be customized using this code: 

.form-all .form-submit-button {

    background-color : #007dc1 !important;

    text-indent : 0px;

    width : auto !important;

    height : auto !important;

     color : #FFFFFF !important;

    text-shadow : 0px 1px 0px #154682 !important;

}

With that you can remove the background it currently has and set up the custom color that matches your website. 

This guide will help you to inject the code to your form: How-to-Inject-Custom-CSS-Codes