Responsive QR Code webpage using HTML5, CSS3 utilities.

If you want to make your card responsive with ease you can use this technique:

.card {
width: 90%;
max-width: 37.5rem;
}

On the smaller screens card will be 90% of the parent (here body), but as soon as the card will be 37.5rem (600px) it will lock with this size.

Also to put the card in the center I advise you to use this code snippet:

.container {
display: grid;
place-items: center;
}

Hope you found this comment helpful 💗💗💗

Good job and keep going 😁😊😉

The final design looks great, but it would have been better to separate the css and the html into different files