[UIBuilder]How can you ensure proper sizing for TextFields within a VisualElement that has a Flex Direction set to "row"?

Here is the screenshot of my UI Builder. The only setting I’ve adjusted is the Flex, while the TextFields have their default settings.

What I want to achieve is that both TextFields can automatically adjust their sizes based on the VisualElement’s size. At the same time, I want to prioritize reducing the whitespace between the Label and the InputArea, rather than reducing the InputArea itself. (I’ve tried manually adjusting the sizes and found that the whitespace doesn’t decrease; it’s the InputArea that shrinks first.) How should I set this up?