Simple client-side todo app that lets users add tasks by typing and pressing Enter, mark tasks as completed with checkboxes, and delete checked tasks using the Delete key (with confirmation). Tasks are persisted in a "taskList" cookie for 7 days, storing each task's label and checked state so the list is restored on page load. The app updates the cookie on every change, supports clearing all tasks, and hides elements with the .flex class during printing to produce cleaner printouts. Works entirely in the browser with no server required.