I recently came across a beautiful to-do list strike off animation designed by Gal Shir and Shaw recreated that effect in CSS. When you click on the list item the square checkbox slides away and strikes off the text.
If you are having trouble with the pen, try the archived copy on GitHub
ToDo List Animation Snippet
See the Pen ☑️ CSS-only Todo List Checkbox Animation by Shaw (@shshaw) on CodePen.0