QR Code Solution Using CSS Flexbox to Center

I was struggling to center the container in the middle of the webpage. I used flexbox and justified the content to the center, but upon using the align-items attribute, my container remained at the top of the page. Using my browser's inspect element, I noticed that my body was not taking up the height of the whole webpage, but only the height of my container. I added the height:100vh to the body, which made it take the entire height space of the webpage. This enabled the align-items:center to work correctly, thus placing my container at the very center of the webpage.