Posts on development — Page 2

CSS sibling-index() and sibling-count() turn an element's position into a number you can drop into calc(), replacing walls of nth-child rules and inline JavaScript for staggered animations and math-driven layouts.

Transitioning an element to height: auto used to mean JavaScript measurements or fragile max-height hacks. interpolate-size and calc-size() finally make it a one-line CSS opt-in.

Iterator helpers bring map, filter, take, and drop to any iterator without spreading into an array first. They went Baseline in 2025, and they change how you handle Maps, Sets, and generators.

The :has() selector is Baseline and fast in 2026. Here's how to use it for parent styling, sibling reactions, and quantity queries without reaching for JavaScript.

CSS finally has real, reusable functions. The new @function at-rule lets you define typed helpers that run in the browser with live values — here is how it works and where it is supported today.

Chrome ships the Soft Navigations API unflagged in 151, giving single-page apps a standardized way to measure LCP, INP, and CLS per route change instead of only on the first load.

Shadow DOM used to mean a blank page until your bundle loaded. The shadowrootmode attribute changed that, and it has been in every major browser since early 2024.

The Origin Private File System gives you byte-level, synchronous file I/O in the browser. Here's how it works, when to reach for it, and why it's the reason SQLite runs well on the web now.

The CSS light-dark() function collapses your two dark-mode palettes into a single declaration. Here is how it works, the color-scheme gotcha that trips everyone up, and how to wire up a manual theme toggle.