Get Pseudo-Element Properties with JavaScript

Assume your CSS looks like:

.element:before {

    content: 'NEW';

    color: rgb(255, 0, 0);

}

To retrieve the color property of the .element:before, you could use the following JavaScript:

var color = window

    .getComputedStyle(document.querySelector('.element'), ':before')

    .getPropertyValue('color')

Passing the pseudo-element as the second argument to window.getComputedStyle allows access to said pseudo-element styles

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