grid responsive props dummy x

[gwyneplaine]

• Support default CSS variables beyond 'initial'
• Standardize how we map over responsive props within components
• Tighten up the types and deduplicate CSS Var generation code
• Add support for non-responsive values to Grid's gap, columns, and areas props.

WHY are these changes introduced?

Fixes #0000

WHAT is this pull request doing?

How to 🎩

🖥 Local development instructions
🗒 General tophatting guidelines
📄 Changelog guidelines

Copy-paste this code in playground/Playground.tsx:

import React from 'react';
import {Page} from '../src';

export function Playground() {
  return (
    <Page title="Playground">
      {/* Add the code you want to test in here */}
    </Page>
  );
}

🎩 checklist

• Tested on mobile
• Tested on multiple browsers
• Tested for accessibility
• Updated the component's README.md with documentation changes
• Tophatted documentation changes in the style guide

[github-actions]

Hi! We noticed there hasn’t been activity on this PR in a while. After 30 days, it will close automatically.

If it’s still relevant, or you have updates, comment and let us know. And don’t worry, you can always re-open later if needed.