HTTP Status Codes: The Complete List, Explained

Every HTTP status code you'll run into, explained in plain English: 200, 301, 302, 304, 400, 401, 403, 404, 429, 500, 502, 503 and more, plus which ones matter for SEO.

https://markodenic.com/http-status-codes/

CSS Grid: grid-template-columns, fr and repeat() Explained

Learn CSS Grid with live examples: grid-template-columns, the fr unit, repeat(), minmax(), auto-fill vs auto-fit, grid-template-areas and responsive grids without media queries.

https://markodenic.com/css-grid/

Fix "Cannot use import statement outside a module" in JavaScript

Why you get "SyntaxError: Cannot use import statement outside a module" and how to fix it in the browser, Node.js, TypeScript and Jest, with the exact change for each case.

https://markodenic.com/cannot-use-import-statement-outside-a-module/

How to Open a Link in a New Tab (HTML target="_blank")

Open a link in a new tab with target="_blank": the HTML, rel="noopener noreferrer" and why it matters, JavaScript window.open(), accessibility, and when you shouldn't do it.

https://markodenic.com/open-link-in-new-tab/

SEO Checklist for Developers: What Actually Matters

A practical SEO checklist for developers: get pages crawled, indexed, ranked and clicked. What Google actually uses, what to skip, and how to check it in Search Console.

https://markodenic.com/seo-checklist-for-developers/

requestAnimationFrame Explained (With Examples)

How requestAnimationFrame works in JavaScript: the animation loop, delta time for smooth motion on any screen, cancelAnimationFrame, throttling scroll handlers, and when to use CSS instead.

https://markodenic.com/requestanimationframe/

CSS ::before and ::after Pseudo-Elements (With Examples)

How CSS ::before and ::after work: the content property, the difference between them, and practical examples like icons, custom bullets, overlays, tooltips and decorative shapes.

https://markodenic.com/css-before-after/

CSS Blob Shape: Organic Blobs with border-radius

Make organic blob shapes with pure CSS using the 8-value border-radius trick, plus an animated morphing blob and gradient blobs for backgrounds.

https://markodenic.com/snippets/css/blob-shape/

I'm co-organizing a Hackathon. Nice prizes, open to everyone.

Check it out!
https://x.com/denicmarko/status/2110065561829069035

How to Send Code Blocks in Discord (With Syntax Highlighting)

Send code in Discord the right way: inline code, multi-line code blocks, syntax highlighting for JavaScript, Python, CSS and more, colored text with diff, and what to do with code that's too long.

https://markodenic.com/discord-code-block/

Is HTML a Programming Language? (And What About CSS?)

Is HTML a programming language? No, it's a markup language. Here's what that means, how HTML, CSS and JavaScript differ, why CSS is a closer call, and why the label doesn't matter for your career.

https://markodenic.com/is-html-a-programming-language/

CSS Wave Shape: Wavy Section Dividers and Backgrounds

Create wave shapes in CSS: a wavy section divider with an inline SVG, a pure CSS scalloped edge with radial-gradient, and an animated wave. Copy-paste examples.

https://markodenic.com/snippets/css/wave-shape/

CSS !important: What It Does and When to Use It

What !important does in CSS, how it beats specificity, how to override an !important rule, how it works with cascade layers and JavaScript, and better alternatives for most cases.

https://markodenic.com/css-important/

URLSearchParams: Read and Update URL Query Parameters in JavaScript

How to use URLSearchParams in JavaScript: get, set, append and delete query parameters, read the current URL, update it without reloading, build fetch URLs, and avoid the common gotchas.

https://markodenic.com/urlsearchparams/

BEM in CSS: Block, Element, Modifier Naming Explained

BEM (Block, Element, Modifier) explained with a real example: the naming rules, how to handle nested elements and modifiers, BEM with Sass, common mistakes, and BEM vs Tailwind and CSS Modules.

https://markodenic.com/bem-css/

Hide Scrollbar in CSS (and Style a Custom Scrollbar)

Hide the scrollbar with CSS while keeping scrolling, hide it completely, hide only the horizontal one, prevent layout shift with scrollbar-gutter, and style a custom scrollbar in every browser.

https://markodenic.com/hide-scrollbar-css/

Will AI Replace Programmers? What's Actually Changing

Will AI replace programmers? Not the job, but parts of the work. What the data shows, which tasks AI handles, who is most exposed, and what developers can do now.

https://markodenic.com/will-ai-replace-programmers/

JavaScript Reserved Words: The Complete List of Keywords

The full list of JavaScript reserved words and keywords, the extra ones reserved in strict mode and modules, words that are only special in context, and the errors you get when you use them as names.

https://markodenic.com/javascript-reserved-words/

Pure CSS Tabs (No JavaScript)

Build tabs with pure CSS and no JavaScript, using radio buttons and :checked, plus the accessible version with buttons and a few lines of JavaScript.

https://markodenic.com/snippets/css/pure-css-tabs/

CSS Class Selector: Single, Multiple and Combined Classes

How CSS class selectors work: adding multiple classes to an element, .a.b vs .a .b vs .a, .b, class vs id, naming rules, specificity, and adding or removing classes with JavaScript.

https://markodenic.com/css-class-selector/

CSS Grid Generator: Visual Layout Builder with Grid Areas

Free CSS grid generator: set columns, rows and gaps, drag to create named grid-template-areas, and copy clean CSS, HTML or Tailwind code.

https://markodenic.com/tools/css-grid-generator/