Four card feature section (using only floats properties for layout)

I'm in no way an expert, but if I'm using floats I'd make sure it displays properly on IE, here's how it looks on IE11: https://imgur.com/a/Dnc3Xgq

Nice job on this project. I agree with Mohamed's comments about using floats. There are more effective ways to lay this out, primarily CSS Grid. Flexbox is another option. You can avoid the clearfix hack by using grid. And, it's much easier to maintain once you learn the syntax.

The HTML looks good to me. The W3C validator isn't returning any errors. My only recommendation would be to have a closer look at the <h1> tag.

<h1>
      Reliable, efficient delivery<br>
      <strong>Powered by Technology</strong>
    </h1>

I think you can make a good case for coding this like you did. When I read the two lines out loud, it makes sense that they go together and could be combined into a single <h1> element like you have them.

When I look at the design, I wonder if the intent is for them to be separate thoughts. Based on the differences in capitalization, it could be argued that the phrase Reliable, efficient, delivery is one thought, and Powered by Technology is a different one—each standalone pieces of content.

Your code is probably correct. But, this is something I would definitely ask the designer to clarify. Again, nice work on this project.