How can I add a class to the input fields/textarea/submit button

I know i can do it with jQuery but Is there a way i can style the form by just adding a predefined class name to the input, textarea, and submit buttons?

Rather than having my styles inline or a external style sheet for the form.

For example

<input class="form-control" type="text" id="fscf_name1" name="full_name" value="" placeholder="Name *">

Instead of

<input style="text-align:left; margin:0; width:99%; max-width:250px;padding:10px 0;" type="text" id="fscf_name1" name="full_name" value="" placeholder="Name *">

Thanks

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