Move over Einstein! Woodcarving has its own Theory of Relativity...
Every part is relative to every other in all sorts of ways but, in particular, depth. Because we start with a single block of wood, things stand out, forward, only because we've taken surrounding wood back. That's it. Without one there can be no other.
When I made this truth fully my own, I made a quantum leap as a woodcarver. So read that paragraph above again. It's what you are doing as a woodcarver in a nutshell!
Thus, to get our Yellow Flag petals to pop, we reduce - push back - the frame. And I use a big handsaw with which to do it.
Dimensions: The thickness of my board of wood was 40mm. I lowered the frame to 15mm, about a third of the full thickness.