QR code component

Nice Work. Just a few things.

1. Apply Resets on all elements rather than just on the HTML

/* use Astrisk instead */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

2. Explore & use more HTML tags: Making the entire Card component out of the main tag doesn't really make sense. It would have been better to use the article tag similar to this:

<main>
    <article>
        <img src="images/image-qr-code.png" alt="qr-code">
        <h1>Improve your front-end skills by building projects</h1>
        <p>Scan the QR code to visit Frontend Mentor and take your coding skills to the next level</p>
    </article>
</main>

3. Use CSS Classes: It makes the code much more understandable & maintainable. Using just tags is not going to be a good solution when it comes to larger projects. I also suggest looking into things like BEM Style CSS

<main>
    <article class="card">
        <img class="card__img" src="images/image-qr-code.png" alt="qr-code">
        <h1 class="card__title">Improve your front-end skills by building projects</h1>
        <p class="card__info">Scan the QR code to visit Frontend Mentor and take your coding skills to the next level</p>
    </article>
</main>