The Background of the text ist gray

Good day,

I have a problem. If I want to learn the created cards in Anki, Anki shows me the background of the text on the back of the card in gray.
When I am creating the cards, I usually copy a text and then I paste it on the back of my card. Could it be because of that? How can I fix the problem?
Thanks in advance

In that case, selecting your cards in the browser, right clicking and changing their note type to basic will solve your issue.