The optional "Buy Now" button can be enabled in your Ecwid Control Panel : System Settings > General > Store
The "Continue" button appears on the checkout pages and uses the same CSS style as the "Buy Now" button and can be enabled in your Ecwid Control Panel : System Settings > General > Migrations > New Continue Button.
Note. The other buttons (add to bag, checkout, continue shopping and place order ) are image based. See this article if you want to customise those.
You can now create a button style using one of the many button design sites on the web, and paste the CSS into Tweak to use that button style for your "Buy Now" and Continue" buttons in Ecwid.
First, create a button. ( this example is using css3buttongenerator.com )
Now copy the CSS. Note, only copy CSS. Some sites create HTML too, we don't need that.
Now, paste this CSS into the CSS button in Tweak.
Save it, and see the results.
That's it. The "Continue" button used on the checkout pages will use the same style.