Drupal CKEditor5 stripping <style> tags

Question

I am upgrading a site from D9 to D10 and thus upgrading from CKEditor4 to CKEditor5. Over time, front end developers have added small custom style definitions in the WYSIWYG areas all over the site. I know it's not ideal, but at this point I need to support these instances. I can't figure out how to get the settings for CKEditor5 right. In the text format full_html I have enabled must buttons, which added the tag in the read only "Allowed HTML tags" field. It still strips out the tags when I try to add the following:

<style>
.partner:not(.partner--sd-concierge) img {
      filter: invert(100%) grayscale(100%) contrast(100%);
    }
</style>

Any help on how to proved would be greatly appreciated.