Chat application in Node.js using

Hello, this was my first ‘serious’ project in Node.js. I created a simple chat appliaction with I don’t know how I’m supposed to share my code here so I will paste link to my project’s github repo:
Also I deployed this site on Heroku:

What do you think about it guys, what should I change? Is it good enough to put it in my portfolio? Thank you for all of yours responses.