CSS Challenges for 200 IQ

Do you ever get that feeling when you’re working on a task, hit a wall with some problem, and something inside you whispers that there has to be a solution? When it seems like all is lost, like you’ve run into a fundamental limit of reality, but your refusal to accept it keeps driving you deeper into spec docs, 10-year-old GitHub threads, and articles from giants who’ve already blazed this trail and shared their findings? And then, after hours of intense brain-grinding, you add that final line of code, refresh the page, and there it is — the exact result you wanted, staring back at you from the screen? That rush of success is probably familiar to every engineer in some form or another. In those moments, I always want to share the win with my colleagues and, if it could help others, write an article about it. In this post, I’ve collected 3 such cases from our work where we came up with solutions that, as far as I know, are pretty unique and haven’t been fully documented before. I invite you to share in the joy of discovering a solution that seemed impossible! Fixed inside a Scroll Container For a warm-up, let’s take an easier task. One of my most popular CodePens is an example of a fixed block inside a scrolling container. People find it via Stack Overflow answers, so it’s an in-demand problem, so it might come in handy for you too. I’ve been working on an Angular component library called Taiga UI for many years. Everything I’ll talk about in this article comes from there, but that’s just the backstory. We won’t need Angular or any of its specifics here. We’re talking pure CSS. Our library uses a custom scrollbar. While modern browsers let you tweak its appearance a bit , for full control over behavior and visuals, we need to place our own elements inside the container to act as the scrollbar. But how do you do that when absolutely positioned elements fly to the top on scroll, and fixed-position ones are pinned to the viewport? Experienced devs will immediately think