Set Autofocus to a Button

Hopefully this is a quick and easy one.

Is there a way to set the Focused State to a button on page load?

I have a landing page that has 4 buttons that sort content. The buttons are All, Blue, Green, Yellow. When the user lands on the page, I would like to have the “All” button to have the focus and thus have the focus button CSS (so it looks highlighted. I’ve been searching for some time, but I can’t figure it out. The buttons themselves do what I want as far as highlighting with you click on them, I just can’t get the “All” to be “automatically selected” when the page loads.

Is this possible?

Thanks in advance.

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