How to deal with styles when sending an email as html?

Question

Django

An HTML message is generated on the server.
It is clear that styling is needed.
What about styles?
Should I prescribe them in each tag in the body of the letter?
After all, if the styles are in css, then the letter will leave without them?

Answer 1

0. Make a copy of the letter on the site. Possibly/preferably with a unique URL for each recipient
1. Read about letter layout for different email clients