Build a basic sign-up form with name, email, and password fields. Use HTML5 constraint validation (required, type="email", minlength) so the form refuses to submit invalid input. Each input must be explicitly associated with a <label> and the submit button must be a real <button type="submit">.

Use <datalist> to attach a free-text autocomplete list to a browser input. The list should suggest Chrome, Firefox, Safari, and Edge, but the user should still be allowed to type any value not in the list.

Use the <output> element together with two number inputs and a <form>'s oninput handler to show the live sum of the two values. Do not require a submit click; the output should update on every keystroke.

Annotate the form below with ARIA so that (a) the password field announces its requirements, (b) a validation error region is announced when an error appears, and (c) the submit button has an accessible name even when its text is just an icon. Do not duplicate any native role unnecessarily.