How to put the corner on the Edge?

Dear Shapr3D Community,
I am trying to put the edge lower or almost to the other corner. So that it is like a ramp within the flat surface. See the red markers. How can I do this?
When I try to adjust it the other corner gets shortened. Hope you understand what I mean :weary:

Greetings from Germany and thanks so much


Extrude it lower “The tilted part”
Welcome :slightly_smiling_face:


Thank you so much!!!