Hello there,
Good Day!!!
We’re here to assist you today!
We don’t have separate settings for to customize email template styles as because we use woocommerce email template(header/footer and body) for to send mail, hence you need to change the background color from woocommerce settings, go to Admin Dashboard -> WooCommerce -> Emails -> Scroll Down to the bottom and try find option “Body background color” or “Base color” or any other color option, just change whatever color you want and this will definitely replicate it in our subscription email.
Please note, that color changing part is global option from woocommerce, hence any changes will applicable to all order emails(New Order/Completed Order/etc).
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