The entire game is web based, and what's more, it stores the entire word library it uses, your score history, etc. locally, and also the share features.
Open the current wordle link on your PC in any browser, right click, and hit "Save As". And with that, you have your personal copy of Wordle that will continue to work. Whether your word will remain synced with what the NYT chooses to pick for a given day in the future is questionable, but if you care about that, pay the games subscription to the Times.