Get all elements containing a class with querySelector

The Element method querySelectorAll() returns a static (not live) NodeList representing a list of the document's elements that match the specified group of selectors.

Use Document.querySelectorAll() to get all the elements. Then use forEach() to set the style in each element:

var elList = document.querySelectorAll('.fa.fa-car');
elList.forEach(el => el.style.display = "none");

Please Note: Some older version of IE (<8) will not support querySelectorAll(). In that case use

Array.from(document.querySelectorAll('.fa.fa-car'))

querySelectorAll() returns a collection of elements. To change their styling you need to loop through them.

Also note that your selector appears to be invalid. Given the FontAwesome class rules I presume you need to select by both classes. Try this:

Array.from(el.querySelectorAll('.fa.fa-car')).forEach(function() {
  this.style.display = "none";
});

Alternatively, as you've tagged the question with jQuery, you could just simplify all that to just:

$('.fa.fa-car').hide();

querySelector only select one element, to select all element you can use querySelectorAll

[].map.call(el.querySelectorAll('.fa fa-car'), n => { n.style.display = 'none'; })

Use method querySelectorAll() See https://www.w3schools.com/jsref/met_document_queryselectorall.asp

You are getting error because querySelectorAll returns an array.Iterate over it and then use style.display

You could do all your operation by iterating the occurence of this class and of course by help of some if clauses.

$('.fa.fa-car').each(function(){
     $(this).css('color','white');
})