JSFiddle - React, Tailwind, and code Playground

HTML

<button id="btn">ЯваСценарій вбиває</button>

JavaScript

let isOver = false;

const elem = document.getElementById('btn');

elem.addEventListener('mouseover', (event) => {
	isOver = true;
}, false);

elem.addEventListener('mouseleave', (event) => {
	isOver = false;
}, false);

document.addEventListener('keypress', ({key}) => {
	if (key === 'a' || key === 'A' || key === 'ф' || key === 'Ф') {
  	alert('Льоша любе Галю');
  }
}, false);