CodePen Blog
423: 2.0 Templates

Stephen and Chris hop on the ol’ podcast to talk about all the ways that Templates are way better in 2.0 land. You’ve always been able to make your own templates, but now you can select one even after you’ve arrived in the editor. There is a new place (the create page) which features bookmarked and official templates (as well as your own). Most importantly, there is a way to set a “default template” now, meaning all new Pens will start with the same setup as the Pen you pick as that.

Time Jumps
* 00:00:40 Templates aren’t new ’round here
* 00:05:23 One important change to templates
* 00:09:59 Official templates from CodePen
* 00:12:55 How to make a pen a template
* 00:18:58 If you want a minimalist experience, use Blank Classic template
* 00:23:32 Some templates are more available than others

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CodePen Blog
Chris’ Corner: ZIP first?

I love ideas that feel clearly better than what was before. I used to feel that way about curved shower curtain bars. Like, instead of the shower curtain being perfectly straight against the edge of the shower, it curves outward. No harm in functionality, but it gives more space inside the shower. It’s just better. There are more factors, though, sadly. Surely they are harder to manufacture, package, and ship, and thus more expensive. Maybe you need longer shower curtains, too? Maybe there isn’t always space for it in smaller bathrooms? I still generally prefer it when possible. It’s an optional improvement.

Here’s another thing like that: Put the ZIP code first.

The big idea is that we should ask for the ZIP code in an address first, not last. Here’s what address forms often look like:
https://blog.codepen.io/wp-content/uploads/2026/04/Screenshot-2026-04-20-at-8.44.04-AM.png
ZIP code is 2nd to last there. Notably, before the City. But if we asked for the ZIP code first, the city would just be implied, saving time filling out the form. Time saved during e-commerce checkouts is a proven way to improve conversion rates.

As that microsite says:

From those 5 characters you can determine the city, the state, and the country. That’s 3 fields. Autofilled. From one input.

That’s just better, right?

Seems better to me, but I bet there are more factors. For one, it’s different, and different might feel weird to users and throw them off, maybe not saving time at all. People have addresses in their head in a certain way/order, and matching that might have its own benefit.

For another, this requires extra code to work. You need some kind of reliable and updated ZIP code matching software. Extra notably, the demo on that page doesn’t even work. I get a 404 for the API they are using:
https://blog.codepen.io/wp-content/uploads/2026/04/Screenshot-2026-04-20-at-8.50.42-AM-1024x313.png
Also, and this I know is true, but I am ignorant about the details: ZIP codes are weird. They have different formats and aren’t necessarily globally unique. So asking for the country first is actually probably best, even if that’s one of the most painful parts of address forms.

Still, maybe it’s an improvement! Maybe try it!

Ya know that screenshot from above? That’s actually from Stripe Elements, which is super incentivized to make payment forms that convert well. This is what they actually do by default (in their own demo):
https://blog.codepen.io/wp-content/uploads/2026/04/Screenshot-2026-04-20-at-8.55.37-AM.png
Me, I’d think that Address field would be full of magic. You could drop in the ZIP code and it would prefill stuff. Or you could single-line type your entire address and it would just know what you mean and deal with it. But no, actually, that’s just what it wants for your street address line, and if you fill it out and press Enter or Tab, it expands to show you all the fields it actually needs. Weird.

The more magic at helping me fill out forms, the better really. Make them accessible. Use all the fancy attributes to make them more understandable for tools and improve UX. Do fancy backend processing. Use the geolocation API. Whatever. Nobody loves filling out forms, they love what the form helps them do.

CodePen Blog
424: File List Optimization

The 2.0 Editor can support hundreds of files per Pen, not to mention folders mixed in which don’t count toward that total. This can be pretty weighty on the DOM and thus adversely affect performance. Especially as each file/folder has children, a variety of event listeners, are drag and drop enabled, etc. “Virtualizing” data like this is a common approach, but we’ve found if we just use IntersectionObserver to see if they are visible or not, “freeze” them if they aren’t, and fade them in and out of life, it’s a great solution.

Time Jumps
* 00:00:42 Files in the 2.0 Editor
* 00:06:26 Virtualization and optimization
* 00:10:49 The IntersectionObserver API

Cinematic single-page cybersecurity portfolio: terminal loader, matrix rain, particles, GSAP animations, security dashboard. Vanilla HTML/CSS/JS.

Tool takes website screenshots. No API key required.

New loader design for website :

/* From Uiverse.io by SchawnnahJ */ 
.loader {
 position: relative;
 width: 2.5em;
 height: 2.5em;
 transform: rotate(165deg);
}

.loader:before, .loader:after {
 content: "";
 position: absolute;
 top: 50%;
 left: 50%;
 display: block;
 width: 0.5em;
 height: 0.5em;
 border-radius: 0.25em;
 transform: translate(-50%, -50%);
}

.loader:before {
 animation: before8 2s infinite;
}

.loader:after {
 animation: after6 2s infinite;
}

@keyframes before8 {
 0% {
  width: 0.5em;
  box-shadow: 1em -0.5em rgba(225, 20, 98, 0.75), -1em 0.5em rgba(111, 202, 220, 0.75);
 }

 35% {
  width: 2.5em;
  box-shadow: 0 -0.5em rgba(225, 20, 98, 0.75), 0 0.5em rgba(111, 202, 220, 0.75);
 }

 70% {
  width: 0.5em;
  box-shadow: -1em -0.5em rgba(225, 20, 98, 0.75), 1em 0.5em rgba(111, 202, 220, 0.75);
 }

 100% {
  box-shadow: 1em -0.5em rgba(225, 20, 98, 0.75), -1em 0.5em rgba(111, 202, 220, 0.75);
 }
}

@keyframes after6 {
 0% {
  height: 0.5em;
  box-shadow: 0.5em 1em rgba(61, 184, 143, 0.75), -0.5em -1em rgba(233, 169, 32, 0.75);
 }

 35% {
  height: 2.5em;
  box-shadow: 0.5em 0 rgba(61, 184, 143, 0.75), -0.5em 0 rgba(233, 169, 32, 0.75);
 }

 70% {
  height: 0.5em;
  box-shadow: 0.5em -1em rgba(61, 184, 143, 0.75), -0.5em 1em rgba(233, 169, 32, 0.75);
 }

 100% {
  box-shadow: 0.5em 1em rgba(61, 184, 143, 0.75), -0.5em -1em rgba(233, 169, 32, 0.75);
 }
}

.loader {
 position: absolute;
 top: calc(50% - 1.25em);
 left: calc(50% - 1.25em);
}

Glassphorism card for beginners:

<body style="background: linear-gradient(45deg, #ff9a9e, #fad0c4); height: 100vh;">
  <div style="
    margin: 50px auto;
    width: 300px;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    text-align: center;
    color: white; font-family: sans-serif;">
    <h2>Glass Card</h2>
    <p>Modern UI design snippet.</p>
  </div>
</body>

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CodePen Blog
425: Debug Logs

As we’re getting close to rounding out the Beta period of the 2.0 editor, we’re trying to close out any bugs we find or users report quickly. They could be browser-support related, network conditions related, account capability related, or just bugs in how the 2.0 editor and technology behind it works. It’s complicated enough that the best way to debug things is to see exactly what the user sees when they have trouble.

A very cool side effect to having built the 2.0 editor with Apollo is that we have a nearly complete look at what is happening in the editor by virtue of the Apollo Cache (we talked about what that is here). We built a tool that can export that as JSON data, and we can load it locally to see exactly what the user sees. It’s a bit fancier than that, doing things like saving browser console error logs and stuff, but that’s the gist of it.

Time Jumps
* 00:00:06 Debug logs
* 00:02:53 How to join the CodePen Discord
* 00:03:56 A super version of it for ourselves
* 00:07:12 What we do with the data logs
* 00:08:55 The importance of supporting versions
* 00:11:45 We can see the debug in a live version of the editor
* 00:14:12 Client side and then adding server side

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