getElementby classname code example
Example 1: javascript get element by class
var elementsArray = document.getElementsByClassName("someclassname");
Example 2: js add class
var element = document.getElementById('element');
element.classList.add('class-1');
element.classList.add('class-2', 'class-3');
element.classList.remove('class-3');
Example 3: how to get element by class name javascript
document.getElementsByClassName("legend").style.display="none";
Example 4: javascript get element by class
const whiteBoxes = document.getElementsByClassName("box-white")