3-box grid responsive layout

Looking pretty good! Nice one!

Some CSS suggestions for you:

1. You have multiple rule blocks for the same class name in the same media query, namely .container. It's best practice to have these all in the same block:

.container {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  height: 500px;
  width: 60%;
  margin: auto;
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  padding: 10px;
}

1. On line 103 in your CSS you have a flex-direction rule but the value looks like it's for a grid rule. Be careful when switching between display: flex and display: grid! It can get confusing

2. As web developers we are normally expected to develop UI in a "mobile-first" approach. For CSS the best way to do this is to structure your style sheet with all the base styles being for mobile and then adding media queries for min-widths instead of max-widths:

// this is my button styling on mobile 
.btn {
  max-width: 100%;
}

// this is my button styling on screens starting at 768px wide (tablets)
@media (min-width: 768px) {
  .btn {
      max-width: 300px;
   }
}

// this is my button styling on screens starting at 1024px wide (desktops)
@media (min-width: 1024px) {
  .btn {
      max-width: 200px; 
   }
}

Hope that's helpful!

It's great! Congrats :)