When I realized that, no individual step is hard in any process. Building this airport I'm standing in right now started with a guy writing the architectural plans on paper. That's not hard for him to do. Then laying the first beam isn't had. The whole thing is really hard. So, just take each step kind of piece by piece and when I was able to do that and stop trying to chase this prize and started putting in the work, things just started coming together.
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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