Display value for element in Node.js pug template doesn't change? Also, jQuery doesn't work?

Code:https://ift.tt/2KNPEzO) So 'box' never shows after I click on one of the things. Its display value is still 'none'. Why is this?2) I would like to use this instead of XMLHttpRequest:$.ajax({ type: 'POST', url: '/doThing', // etc... }); but the console always comes back with 'Uncaught ReferenceError: $ is not defined'. I've changed where the dots go, made a separate script for jQuery only, but I still get the same reference error. What am I doing wrong?Thanks in advance.

Submitted May 09, 2018 at 06:03PM by SnowyIrene