Properly reset css based on https://meyerweb.com/eric/tools/css/reset/

[khinshankhan]

Pull request checklist

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update
• Refactoring
• Build related changes
• Documentation content changes
• Other (please describe):

What is the new behavior?

Pretty sure the way js/ ts objects work, newer entries (top down) with the same key simply override older entries. This means the current

{
    content: "",
    // @ts-ignore
    content: "none",
}

is actually just

{
    content: "none",
}

which is technically wrong. Css does override as well but only if the style is supported. I'm not a stitches expert but I believe we can have support queries like so?

{
    "@supports (<test style here, unapplied>)": {
      // apply style here
    },
}

I also saw that the default behavior for tables was a bit off looking at https://meyerweb.com/eric/tools/css/reset/

Does this introduce a breaking change?

• Yes
• No

Other information

I don't believe the styling for pseudo blockquote elements is breaking, however the table's border collapse may be breaking(?)

If you'd like, I could open separate prs since the table styling may not be alright.

[khinshankhan]

The initial bug that required the two content keys does seem to be resolved though https://bugs.webkit.org/show_bug.cgi?id=20032