Answers for "how to setattribute for a button js"

put new attribute on html tag using javascript

// Here's what you do for the style attribute
span.setAttribute("style", "width:110%;float:center;left-margin:-10px;top-margin:-10;");

js setattribute

const link = document.querySelector('a');

console.log(link.getAttribute('href'));
link.setAttribute('href', 'https://yandex.ru');
link.innerText = 'The Next Link';

const mssg = document.querySelector('p');

console.log(mssg.getAttribute('class'));

mssg.setAttribute('class', 'success');
mssg.setAttribute('style', 'color: green;');