Help me please…..fix a theme

Hello

Please look at he url.
I am using theme Astrid from Athemes
As you see all the posts are showed in brief.
I would like the newest post, which is showed on top of the post list, to be showed fully opened and not brief.
The other posts in the list I want to be shown in brief

So again….the newest post should display in full.

Can someone help me with this ?

Thank you so much

Petter

The page I need help with: [log in to see the link]