An example tooltip on jqueryui.com/tooltip/ displays the tooltip itself ("What widget is this") when hovering with a small font size.

I cannot duplicate this font size. When I try to match their pattern, the tooltip is displayed in large font.

I downloaded and applied the style.css file used in their example. The font specification must be buried there; but I canβt find him.
(Maybe the solution is to create a custom theme, although I use my style.css file. This seems too complicated for what I want to do.)
What am I missing?
Thanks.
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