You can apply CSS to the <title> element, but not to the style attribute (since it is intended for all elements except BASE, BASEFONT, HEAD, HTML, META, PARAM, SCRIPT, STYLE, TITLE ").
I don’t know a single browser that will use CSS to render the title in browser tabs or in headers.
You can, however, do something like:
head { display: block; } title { display: block; font-size: 200%; font-weight: bold; }
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