how to add multiple css class in javascript code example

Example 1: add multiple class list at once in js

elem.classList.add("first");
elem.classList.add("second");
elem.classList.add("third");

is equal to :

elem.classList.add("first","second","third");

Example 2: css multiple classes

//HTML Code
<div class = 'firstClass secondClass'></div>

//CSS Code
.firstClass.secondClass {
  
}

Example 3: css change multiple classes

.objectOne, .objectTwo { /* We will now both be changed */
	margin: 0 auto; 
}

Example 4: css assign multiple classes to one element

To specify multiple classes, separate the class names with a space,
e.g. <span class="classA classB">.
This allows you to combine several CSS classes for one HTML element.

Example 5: css multiple classes

<div class="a-class another-class"></div>