How to send a beautiful email with Mailer Yii2?

Question

Yii

In general, in the admin panel, when processing an order, the admin confirms the order by sending a coupon to the client, which he will also need to confirm within an hour (Confirmation has not yet been implemented)
Implemented sending.
Sending, of course, will be redone so that in the admin panel you only need to enter the date of the coupon and select a doctor. But that's not the point.
As the same send beautiful letters with styles.
I understand that you need to use compose('template' , 'data') ? Or how

Answer 1

Sorry, I didn’t really read into the code, but I realized that the question is precisely in “how to make a beautiful letter”, and not how to implement it technically (everything is simple, in fact, a normal view).
Use https://foundation.zurb.com/emails.html. Very pretty html emails come out. Everything is pretty easy to do.

Answer 2

What for you resulted a heap of the code not concerning a question? What difference does it make how you save, calculate, etc. to a letter template?
Required reading (to the end from the beginning without skipping):
https://www.yiiframework.com/doc/guide/2.0/en/tuto...