Only basic CSS, using Flexbox

Hey, great work on this one. The layout both desktop and mobile is good and it responds and scales very well on screen changes.

Also, great that you adopting certain methodologies, although I don't know what is SMACSS but hey, if you got it, that's really great.

Some suggestions would be:

• Always have a h1 element on a webpage. On this one, the h1 would only be a screen reader text. It might seem new to you, but this is intended for screen reader users. The h1 element would look like:

<h1 class="sr-only">Frontendmentor car collections examples</h1>

The sr-only class is just a css stylings, you can search some up in google. This h1 would be the first text element inside the main.

• Avoid using height: 100% or height: 100vh on an element. This will make the element's height limited to the viewport's height. On your body and main remove those css styling. That is a bad practice. Instead, on your main element. Add these:

align-items: center; # centers the content vertically
min-height: 100vh; # makes sure it have necessary height and will expand

• On the section elements, you don't need to use transform on those element. Let the main flex container centers them properly, just add padding to a certain parent element.
• An a tag doesn't have a type attribute. Remove those, button element and input have those.

Overall, it looks good. Great work again.