Only styles specified via the style
attribute can be read through the style
property. This means that the styles set
in the CSS file cannot be read.
Let's take a look at an example. Let's say we have the following element:
<div id="elem">
text
</div>
Let the following styles be set for it in the CSS file:
#elem {
color: red;
}
Let's get a reference to an element into a variable:
let elem = document.querySelector('#elem');
Let's try to read the style value:
console.log(elem.style.color); // shows ''