Inserting different images in code

Hello!

I’m finalizing details on my blog. I would like to add different images to illustrate the name of the categories before articles (as in the link below, I would like to put an image of Europe for the Europe category, then a pic of Asia for the Asia category etc.):

http://www.ouvrirlemonde.com/category/destinations/europe/
http://www.ouvrirlemonde.com/category/destinations/asie/

Do you think it is possible in the php editor?

Thank you!

Marion

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