add class remove class javascript code example
Example 1: javascript remoev css class
document.getElementById("myElementID").classList.remove("class_name");
Example 2: javascript add class
var myElement = document.querySelector('#myElement');
myElement.classList.add('some-class');
myElement.classList.add('one-class', 'one-more-class');
myElement.classList.remove('any-class');
Example 3: es6 add and remove class
let el = document.getElementById('container');
el.classList.remove('first');
el.classList.add('first');