How to undelete Emails

Hi there all, I've just deleted all my icloud emails on the server directly via www.cloud.com because my iCloud storage was full. What I DIDN'T know is that all these emails would also be deleted im my Mail App on my Mac computer. I only wanted to delete the server side emails as thesis how it normally works with other Email services. Can anyone be so kind and tell me how I can retrieve my emails that were deleted in my Email programme from the iCloud folder on my Mac??

Many thanks in advance

Gary