Responsive Design Portfolio Using CSS Grid & Flexbox

Fun project to practice some CSS grid and flexbox. I think it's quite pixel-perfect, but I wonder what you think about the skill boxes. Are they designed right? Wouldn't it make way more sense if they had some logical sizes? Is there someone who made this section pixel-perfect without being specific on each block?

Then about the slider. I know I can be done with pure javascript, but who is doing that these days? I always use swiper.js for this kind of slider. Are there reasons to code these manually besides practicing?