How to make text in spans_manual interface scrollable?

How can I make the text in a spans_manual interface fixed height and scrollable? In the config of my custom recipe, I tried both

"global_css": ".prodigy-root[data-prodigy-view-id='spans_manual'] .prodigy-content  { overflow: auto; height: 400px}"


"global_css": ".prodigy-spans { overflow: auto; height: 400px}"

, but neither of them worked.

This one

"global_css": ".prodigy-content { overflow: auto; height: 400px}"

does work (i.e. making the text in spans_manual scrollable), but it also made every other interface the same height too (which is undesired). How can I make just the spans_manual scrollable?

FYI, the spans_manual interface is among many others in a block:

blocks = [
        {"view_id": "text", "text": "some text here"},
        {"view_id": "html"},
        {"view_id": "text_input", "field_id": "text_input_1",  "field_rows": 3, "field_label": "summary", "field_placeholder": "write a summary"}, 
        {"view_id": "spans_manual"}, 

Thank you!

I believe this is a duplicate of a follow-up here.