MailPoet – Post Notification – Excerpt alignment & Number of characters

Good morning,
Recently I switched to MailPoet and I am building a post notification.

First, how do I change the alignment of a post’s excerpt?

Second, how do I change the number of characters shown? (if possible)

I tried different custom css in Customization but it did not work.

Could you help me please?

PS: Picture showing Text who need to be align and number of characters changed

Wishing you and your dears to be safe,

Thomas