Elements should not rely on ARIA attributes for styling or behavior.

[robdodson]

In earlier elements like <howto-radio-group>, I relied on aria-* for styling and behavior. Instead, ARIA should be an implementation detail.

So instead of styling aria-checked I would expose a checked attribute/property on the element, and style that. Setting checked would, as a side effect, also set aria-checked. We should use this pattern throughout.

• [ ] Accordion
• [x] Checkbox
• [ ] Radio Group
• [x] Tabs
• [x] Tooltip
• [ ] Tree