JSFiddle - React, Tailwind, and code Playground

HTML

<button>A</button>
  <button>B</button>
  <button>C</button>
  <button>D</button>
  <button>E</button>
  <button>F</button>
  <button>G</button>

JavaScript

function seqFadeOut(jq, i) {
	jq.eq(i).fadeOut(500, function() {
		seqFadeOut(jq, i+1);
	});
}
seqFadeOut($("button"), 0);