Loading component-children size problem

while using dcc.Loading component, its children’s size becomes impossible to change.
I want the graph to be 100vh like its row parent like this:

but instead this is what i get when using the Loading component:
I also tried the bdc Spinner and got the same result.
What am I doing wrong?
here’s the snippet of my code where i use the components:

Your help will be much appreciated!