can’t select submit class

I am able to target .wpcf7-textarea in my custom css and make some css changes there. However when I try to target the submit button, it seems like it is ignored. I instead have to target the following which makes even less sense to me:

.button:not(.components-button):not(.customize-partial-edit-shortcut-button), input[type=button]:not(.components-button):not(.customize-partial-edit-shortcut-button), input[type=reset]:not(.components-button):not(.customize-partial-edit-shortcut-button), input[type=submit]:not(.components-button):not(.customize-partial-edit-shortcut-button)

I have tried adding a html-class to the shortcode, but then I can’t seem to target that and it is ignored:

[contact-form-7 id="100" title="Message"html_id="contact-form-1234" html_class="form contact-form"]

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