Ecwid have just released new buttons for Ecwid storefronts for all Ecwid users.
They are enabled for all new users and all existing users can enable that functionality in Ecwid control panel > Settings > What's new > Improved appearance of storefront buttons.
All e-shop designer themes have been updated to work with all Ecwid stores, regardless of whether the new feature is enabled or disabled.
How to update your existing e-shop designer themes and tweaks.
If an update is available for any theme or tweak, and "update" link will appear for that Theme or Tweak on the "Manager" page in your e-shop designer account and in the Ecwid Control Panel Settings > Design > Theme Designer page if you are using the Ecwid Theme Designer App.
If you are using the Ecwid Theme designer App, click on the appropriate "update" link.
If you are not using the Ecwid Theme Designer App, in your e-shop designer account, go to the "Manager" page and click the "update" link for the theme or tweak, then copy the updated CSS into your Ecwid Control Panel Settings > Design > CSS Themes to replace your current active theme.
Note. the update may take some time (perhaps a minute or two) in some cases, please be patient.
I plan to add more themes to e-shop designer soon that will have the same look as the new Ecwid buttons with the usual colour change options.