$//$ HTML for the up$,$ down, and done buttons

const upButtonHtml $=\text{'}\text{'}$;

const downButtonHtml $=\text{'}\text{'}$;

const doneButtonHtml $=\text{'}\text{'}$;

$$($function$()\{$

$$("$#addBtn"$).$click$($addBtnClick$)$;

$//$ TODO: Add item if user presses Enter

$\})$;