1. Probably not in general? Maybe with a vertical <input type="range"> for each item and a lot of server-generated CSS hackery, for small lists? 2. Use ARIA 3

1. Probably not in general? Maybe with a vertical <input type="range"> for each item and a lot of server-generated CSS hackery, for small lists? 2. Use ARIA 3. Use position: absolute? 4. Create it with position: absolute/relative and use CSS :hover selector to show it (or see #5 for explicit open/close) 5. Use <details> or a checkbox along with the appropriate CSS