You want to be the best, you MUST put the long yards in! Nothing comes easy in life so stop wishing and start DOING! So many people would rather bitch and moan than help themselves. Dont be one of those negative drainers, start today, make a small change and keep going forwards with this attitude!
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:defined

The :defined CSS pseudo-class represents any element that has been defined. This includes any standard element built in to the browser, and custom elements that have been successfully defined (i.e. with the CustomElementRegistry.define() method).
:defined css reference