[Beta] Inaccessible UI Components

Accordion a11y issues

• When an Accordion trigger is focused, pressing down/up should focus the next/previous trigger.
• When an Accordion trigger is focused, pressing space should expand/contract its panel.
• The Accordion trigger should be a <button> rather than a <a>.
• The Accordion trigger should be wrapped in a h tag.
• The Accordion trigger should have an aria-expanded attr set to true when open.
• The Accordion trigger should have an aria-controls attr.

The same goes for the Tabs component (found in the sidebar and on code blocks), it fails a11y in many ways. I'd suggest you look at UI libs like Radix or ReachUI which provide high-quality, accessible UI components.

先找出側邊欄和程式碼區塊中使用的 Accordion 與 Tabs 元件，然後將其行為與 issue 中連結的 Radix 和 ReachUI 參考進行比較。當兩個元件都完成列出的鍵盤互動，以及 button、heading、aria-expanded 和 aria-controls 的要求後，即表示完成。