CSS :is

There are scores of developers who hate CSS; don't get it, don't want to get it, etc. Most of that is either down to inefficiencies within the language or misunderstanding of how to properly construct a website structure. I mostly love CSS but there are some parts of the language that I always hated, like having to repeat very similar selectors. That's why I was so happy when I saw CSS :is ; a method of avoid duplication within your selector structure!

You all remember this mindless CSS repetition:

section h1,
section h2, 
section h3,
article h1,
article h2,
article h3 {
  /* styles here */
}

I always loathed having to do that -- lots of maintenance cost and bloated CSS files. This is where :is comes to the rescue:

:is(section, article) :is(h1, h2, h3) {
  /* styles here */
}

is: is a perfect summary of how a tiny addition to the CSS language can make a developer's life just a bit easier!