Can I apply css to custom element

Hi I’m working on the customization of the universal login form but running into issues getting css to apply to elements I add myself to the form. When I apply css to default login form elements it works fine but when I add something like this myself:

<p className="test">header-auth0</p>

then the CSS like this for example

font-size: 1000px;

the css never seems to apply. Just wondering is there limitations on how you can use CSS on elements that you add yourself, or is it a limitation of my account?

You’ll want class instead of className assuming you are modifying your New Universal Login Template.

   <footer class="footer">

And this in a style tag

      .footer {
        background-color: #007bad;
        position: absolute;
        bottom: 0;
        left: 0;
        padding: 16px 0;
        width: 100%;
        color: white;
        /* Use a high z-index for future-proofing */
        z-index: 10;