# Shimmer Text

> A band of light that sweeps across text, the way a busy interface says "still working on it". Looping, on hover, or following the pointer.

Text effects · text, shimmer, loading, hover · HTML, CSS, vanilla JS · no dependencies · updated 2026-10-16
Demo: https://kodza.dev/components/text-shimmer/

## Files

The code below, served as files: byte for byte what the Kodza site copies (the CSS includes its theme guard).

- [`kodza-text-shimmer.css`](https://kodza.dev/registry/text-shimmer/kodza-text-shimmer.css) · 3.1 KB
- [`kodza-text-shimmer.js`](https://kodza.dev/registry/text-shimmer/kodza-text-shimmer.js) · 2.4 KB
- [`kodza-text-shimmer.html`](https://kodza.dev/registry/text-shimmer/kodza-text-shimmer.html) · 0.2 KB · the markup, to adapt and paste into your page

**Can you run shell commands? Download the CSS and the JS, don't retype them.** Retyping costs thousands of tokens and can drop or change lines of the CSS. Put the files where your stack expects them (Use it says where: change the `-o` paths):

```bash
curl -fsSL --create-dirs -o kodza/kodza-text-shimmer.css https://kodza.dev/registry/text-shimmer/kodza-text-shimmer.css
curl -fsSL --create-dirs -o kodza/kodza-text-shimmer.js https://kodza.dev/registry/text-shimmer/kodza-text-shimmer.js
```

Then load the files from your page as Use it shows, instead of pasting the content. The HTML is the part you adapt (text, links, modifiers): paste it from the Code section. Copy the CSS and the JS from the Code section only if you can't run commands, exactly as they are. (Windows PowerShell: `curl.exe`.)

## API

- Root: `.kodza-shimmer--pointer`
- Variables (set them on the root element itself: it declares its own defaults):
  - `--kz-shimmer-base: rgba(10, 10, 10, 0.42)`
  - `--kz-shimmer-light: #0a0a0a`
  - `--kz-shimmer-width: 18%`
  - `--kz-shimmer-duration: 2.2s`
- Modifiers: `.kodza-shimmer--hover`, `.kodza-shimmer--pointer`
- Lifecycle: `kodza:init` / `kodza:destroy` on `document`, with `{ detail: { root } }` to target a container.

## Dark mode

The values Kodza uses on a dark background (`#0a0a0a`). For a page that follows the system theme, add them after the component's CSS:

```css
@media (prefers-color-scheme: dark) {
  .kodza-shimmer {
    --kz-shimmer-base: rgba(255, 255, 255, 0.4);
    --kz-shimmer-light: #ffffff;
  }
}
```

A site with its own theme switch puts the same rules under its dark selector instead (`[data-theme="dark"] .kodza-shimmer { … }`); a single dark section, under that section's class.

## Use it

### Plain HTML page

- CSS: `kodza/kodza-text-shimmer.css` next to the page (the Files commands as they are), linked in `<head>`: `<link rel="stylesheet" href="kodza/kodza-text-shimmer.css">`. Without a shell, paste it in a `<style>` in `<head>` instead. It only touches `kodza-` classes.
- HTML: where the component goes. Paste it as many times as you need: instances never interfere.
- JS: `kodza/kodza-text-shimmer.js`, loaded with `<script src="kodza/kodza-text-shimmer.js" defer></script>` in `<head>`. Without a shell, paste it in a `<script>` before `</body>` (or in `<head>`: it waits for the page). One copy per page, whatever the number of instances.
- Restyle with the `--kz-…` variables, set on the component's root element itself (the root declares its own defaults, so a value on an ancestor is ignored), and with the modifiers / attributes listed under API.
- Font: it takes the page's own. The Kodza look is Geist: `<link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Geist:wght@400;500;600;700&family=Geist+Mono:wght@400;500&display=swap">`.
- Content added later (AJAX navigation, a SPA route, a builder preview): start it with `document.dispatchEvent(new CustomEvent('kodza:init', { detail: { root: container } }))`; before removing it, the same call with `'kodza:destroy'` stops it and puts the original markup back.

### Claude artifact (claude.ai)

- Paste the CSS in a `<style>` and the JS in a `<script>` at the end, in the artifact itself: it loads stylesheets only from Google Fonts and scripts only from a few CDNs, so no `<link>` or `<script src>` to Kodza.
- Writing the artifact file with a shell? Insert the downloaded files (Files) with a command instead of retyping them: a line `KODZA-CSS` alone inside the `<style>`, `KODZA-JS` inside the `<script>`, then `sed -e '/^KODZA-CSS$/{r kodza/kodza-text-shimmer.css' -e 'd' -e '}' -e '/^KODZA-JS$/{r kodza/kodza-text-shimmer.js' -e 'd' -e '}' page.html > artifact.html`.
- Font: load Geist from Google Fonts (allowed): `<link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Geist:wght@400;500;600;700&family=Geist+Mono:wght@400;500&display=swap">`.
- Dark mode: the viewer sets `data-theme="dark"` or `"light"` on `<html>`, or nothing when it follows the system. Write the Dark mode rules twice: inside `@media (prefers-color-scheme: dark)` with `:root:not([data-theme="light"])` in front of each selector, and with `:root[data-theme="dark"]` in front of each selector.

### WordPress

- HTML: a **Custom HTML** block (or a pattern / template part). WordPress keeps this markup as it is only for users allowed to post unfiltered HTML (Administrators; Super Admins on multisite): for anyone else it strips tags such as `<svg>`, `<input>` or `<dialog>`, so add it from the theme (a pattern or template part) instead.
- This one is inline (it flows like a word): pasted alone, many themes leave it at the edge of the page (block themes, and classic ones like Twenty Twenty-One or Blocksy), so put the Custom HTML block inside a **Group** block to line it up with the text.
- CSS and JS: the downloaded files go in the theme, under `wp-content/themes/<your-theme>/kodza/` (the child theme if there is one), enqueued from its functions.php (or a code-snippets plugin):
  ```php
  add_action('wp_enqueue_scripts', function () {
    $dir = get_stylesheet_directory() . '/kodza/';
    $uri = get_stylesheet_directory_uri() . '/kodza/';
    wp_enqueue_style('kodza-text-shimmer', $uri . 'kodza-text-shimmer.css', [], filemtime($dir . 'kodza-text-shimmer.css'));
    wp_enqueue_script('kodza-text-shimmer', $uri . 'kodza-text-shimmer.js', [], filemtime($dir . 'kodza-text-shimmer.js'), true);
  });
  ```
  Scoped to `kodza-` classes, the CSS never touches the theme. One copy of the JS, whatever the number of blocks.
- Not in Additional CSS: WordPress refuses this one there, it contains a `<…>` type that looks like markup to it.
- Theme with AJAX page transitions: fire `kodza:init` on the new content after each swap (and `kodza:destroy` on the old one).
- Performance plugin (WP Rocket, LiteSpeed Cache, Perfmatters…) with **Delay JavaScript execution** turned on: add `kodza` to the scripts it must not delay. Otherwise the component waits for the visitor's first scroll, tap or mouse move, and that first click can be lost.
- Colours: it takes the colour of the text around it (or keeps its own monochrome): nothing to point at the theme.
- WordPress turns straight quotes and `--` into typographic ones in the text of a Custom HTML block (not inside `<code>` or `<pre>`).

#### With Elementor

- HTML: an **HTML** widget (Elementor shows it to administrators only). It keeps the code exactly as pasted, straight quotes included.
- CSS and JS: as above. Elementor's Site Settings → Theme Style styles every button, field, link and image of the page, components included; the theme guard at the end of the CSS keeps the component's buttons, fields and link colours as they are.
- The Elementor editor redraws each widget after the page has loaded: without the script below, the component stays still in the editor preview (the published page works). Add it once per site, in the footer like the component's script (`kodza/elementor-editor.js`, or a code-snippets plugin):

```js
// Kodza in the Elementor editor: the editor redraws each HTML widget after the page has loaded.
// Start Kodza in what it draws, stop it in what it replaces or removes. Once per site.
window.addEventListener('elementor/frontend/init', () => {
  if (!elementorFrontend.isEditMode()) return;
  class KodzaWidget extends elementorModules.frontend.handlers.Base {
    onInit() {
      super.onInit();
      this.kodza = [...this.$element[0].children];
      document.dispatchEvent(new CustomEvent('kodza:init', { detail: { root: this.$element[0] } }));
    }
    onDestroy() {
      super.onDestroy();
      this.kodza.forEach((root) => document.dispatchEvent(new CustomEvent('kodza:destroy', { detail: { root } })));
    }
  }
  elementorFrontend.elementsHandler.attachHandler('html', KodzaWidget);
});
```

- No child theme: everything can go in the HTML widget instead, `<style>` with the CSS, the HTML, then `<script>` with the JS. It works on the page and in the editor without the script above.

### Shopify

- Files: `assets/kodza-text-shimmer.css` and `assets/kodza-text-shimmer.js` (the Files commands with `-o assets/…`).
- In the section: `{{ 'kodza-text-shimmer.css' | asset_url | stylesheet_tag }}` and `<script src="{{ 'kodza-text-shimmer.js' | asset_url }}" defer></script>`, then the HTML.
- The theme editor re-renders sections: restart them with
  `document.addEventListener('shopify:section:load', (e) => document.dispatchEvent(new CustomEvent('kodza:init', { detail: { root: e.target } })));`
  and the same with `shopify:section:unload` → `kodza:destroy`.

### React / Next.js

- Files, side by side (e.g. in `components/kodza/`): `ShimmerText.tsx` (below), the CSS block under Code saved as `text-shimmer.css` and the JS block as `text-shimmer.js`, both as they are. The HTML block is already inside the component: skip it.
- Use it: `import { ShimmerText } from '@/components/kodza/ShimmerText';` then `<ShimmerText>Follow the light</ShimmerText>`. Props: `variant` ("hover", "pointer", or several in an array), `vars` (the `--kz-…` variables listed under API, e.g. `vars={{ '--kz-shimmer-base': … }}`), `children` (the text, plain), `className`, `style` and the other props of its `<span>` (`onClick`, `aria-…`).
- Next.js App Router: it is a Client Component already (`'use client'`). Pages Router: Next.js takes global CSS only in `pages/_app`, so move the `import './text-shimmer.css'` line there.
- Safe under StrictMode, client-side navigation and prop changes: when a prop changes, the `key` gives React a fresh element, `kodza:destroy` stops the script on the old one and `kodza:init` starts it on the new one.

```tsx
'use client';
// Kodza — Shimmer Text, for React. From https://kodza.dev/components/text-shimmer/
// Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license
// Next to this file: text-shimmer.css and text-shimmer.js, the component's CSS and JS from Kodza, as they are.
// Yours to edit: the markup is plain JSX below.
// The script changes this markup once React has rendered it (it adds layers, splits text, moves
// nodes), so React must not patch it afterwards. When a prop changes, the key gives React a fresh
// element: kodza:destroy stops the script on the old one, kodza:init starts it on the new one.
import { useRef, useEffect, type ComponentPropsWithoutRef, type ComponentRef, type CSSProperties } from 'react';
import './text-shimmer.css';

type Variant = "hover" | "pointer";

export type ShimmerTextProps = Omit<ComponentPropsWithoutRef<'span'>, "children" | "variant" | "vars"> & {
  /** Modifier class(es): .kodza-shimmer--hover, .kodza-shimmer--pointer (default: pointer, the one the script runs on; [] for none) */
  variant?: Variant | Variant[];
  /** Settings, as CSS variables on the root */
  vars?: {
    /** default: rgba(10, 10, 10, 0.42) */
    "--kz-shimmer-base"?: string | number;
    /** default: #0a0a0a */
    "--kz-shimmer-light"?: string | number;
    /** default: 18% */
    "--kz-shimmer-width"?: string | number;
    /** default: 2.2s */
    "--kz-shimmer-duration"?: string | number;
  };
  /** The text, plain: the script reads it and rebuilds the markup around it */
  children?: string;
  className?: string;
};

export function ShimmerText({ variant = "pointer", vars, children = "Follow the light", className, style, ...rest }: ShimmerTextProps) {
  const ref = useRef<ComponentRef<'span'>>(null);
  const classes = ["kodza-shimmer", ...([] as string[]).concat(variant ?? []).map((v) => `kodza-shimmer--${v}`), className].filter(Boolean).join(' ');
  // Everything the markup is made of: when it changes, React gets a fresh element (see the top)
  const key = JSON.stringify([classes, vars, children, style, rest]);

  // Starts the script on this element once React has rendered it, stops it when it goes
  useEffect(() => {
    const root = ref.current;
    let live = true;
    // @ts-ignore: a plain script, no types to find
    import('./text-shimmer.js').then(() => {
      if (live) document.dispatchEvent(new CustomEvent('kodza:init', { detail: { root } }));
    });
    return () => {
      live = false;
      document.dispatchEvent(new CustomEvent('kodza:destroy', { detail: { root } }));
    };
  }, [key]);

  return (
    <span key={key} {...rest} className={classes} style={{ ...vars, ...style } as CSSProperties} ref={ref}>{children}</span>
  );
}
```

## Code

```html
<span class="kodza-shimmer">Thinking about your request</span>

<span class="kodza-shimmer kodza-shimmer--hover">Shines when you look</span>

<span class="kodza-shimmer kodza-shimmer--pointer">Follow the light</span>
```

```css
/* Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license */
/* Kodza — Shimmer Text
   A band of light that sweeps across the text, the way a busy interface says
   "still working on it". Three behaviours:
     (default)  an endless, quiet sweep
     --hover    one sweep each time the pointer comes in
     --pointer  the light follows the pointer (with the small script)
   It stays readable at every moment, and still for reduced motion.
   Everything is tuned with the --kz-shimmer-* variables. */
.kodza-shimmer {
  --kz-shimmer-base: rgba(10, 10, 10, 0.42);
  --kz-shimmer-light: #0a0a0a;
  --kz-shimmer-width: 18%;
  --kz-shimmer-duration: 2.2s;
  --kz-shimmer-x: 50%;

  display: inline-block;
  color: var(--kz-shimmer-base);
  background-image: linear-gradient(
    100deg,
    var(--kz-shimmer-base) calc(50% - var(--kz-shimmer-width)),
    var(--kz-shimmer-light) 50%,
    var(--kz-shimmer-base) calc(50% + var(--kz-shimmer-width))
  );
  background-size: 300% 100%;
  background-position: 100% 0;
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: kodza-shimmer-sweep var(--kz-shimmer-duration) linear infinite;
}

@keyframes kodza-shimmer-sweep {
  from { background-position: 100% 0; }
  to { background-position: 0 0; }
}

/* One sweep per visit */
.kodza-shimmer--hover {
  animation: none;
}

.kodza-shimmer--hover:hover {
  animation: kodza-shimmer-sweep calc(var(--kz-shimmer-duration) * 0.55) cubic-bezier(0.45, 0, 0.25, 1) 1;
}

/* The light sits where the pointer is (set by the script), and fades in and out */
.kodza-shimmer--pointer {
  animation: none;
  background-image: radial-gradient(
    circle at var(--kz-shimmer-x) 50%,
    var(--kz-shimmer-light) 0,
    var(--kz-shimmer-base) var(--kz-shimmer-spot, 0px)
  );
  background-size: 100% 100%;
  transition: --kz-shimmer-spot 0.4s ease;
}

.kodza-shimmer--pointer.is-lit {
  --kz-shimmer-spot: 4.5em;
}

@property --kz-shimmer-spot {
  syntax: "<length>";
  inherits: true;
  initial-value: 0px;
}

/* Windows high contrast: plain text */
@media (forced-colors: active) {
  .kodza-shimmer {
    background: none;
    color: CanvasText;
    -webkit-text-fill-color: CanvasText;
  }
}

@media (prefers-reduced-motion: reduce) {
  .kodza-shimmer,
  .kodza-shimmer--hover:hover {
    animation: none;
    background: none;
    -webkit-text-fill-color: var(--kz-shimmer-light);
  }
}

/* Theming example — on a dark background:
.dark-section .kodza-shimmer {
  --kz-shimmer-base: rgba(255, 255, 255, 0.4);
  --kz-shimmer-light: #ffffff;
}
*/

/* kodza-guard af4fd6ccd15b — generated by Kodza, do not edit.
   Theme guard: keeps a site's own CSS (WordPress themes, Bootstrap, CSS resets…) off this
   component. :not(#_) is always true and weighs as much as an id, so these lines win over
   theme rules made of classes and tags. Customise the component through its --kz-* variables. */

/* What the browser gives, on everything the component leaves to it */

.kodza-shimmer:not(#_) {
  box-sizing: revert;
}
```

```js
// Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license
// Kodza — Shimmer Text
// Only needed for the --pointer variant: moves the light to the pointer's position.
(() => {
  const SELECTOR = '.kodza-shimmer--pointer';
  // One instance. Everything it starts is tied to `signal`, so kodza:destroy stops it all
  function mount(text, signal) {
    text.addEventListener('pointermove', (event) => {
      const rect = text.getBoundingClientRect();
      text.style.setProperty('--kz-shimmer-x', `${((event.clientX - rect.left) / rect.width) * 100}%`);
    }, { signal });
    text.addEventListener('pointerenter', () => text.classList.add('is-lit'), { signal });
    text.addEventListener('pointerleave', () => text.classList.remove('is-lit'), { signal });
  }

  // Kodza lifecycle, the same in every component: `kodza:init` starts the instances inside
  // event.detail.root (the whole page by default), `kodza:destroy` stops them and puts their
  // markup back. For themes and apps that swap content without a page load.
  const instances = new WeakMap();
  const find = (scope = document) => [scope, ...scope.querySelectorAll(SELECTOR)].filter((el) => el.matches?.(SELECTOR));
  const init = (scope) => find(scope).forEach((root) => {
    if (root.classList.contains('is-ready')) return; // already running, maybe from another copy of this script
    const controller = new AbortController();
    instances.set(root, { controller, html: root.innerHTML, attrs: [...root.attributes].map((a) => [a.name, a.value]) });
    mount(root, controller.signal);
    root.classList.add('is-ready');
  });
  const destroy = (scope) => find(scope).forEach((root) => {
    const instance = instances.get(root);
    if (!instance) return;
    instances.delete(root);
    instance.controller.abort();
    [...root.attributes].forEach((a) => root.removeAttribute(a.name));
    instance.attrs.forEach(([name, value]) => root.setAttribute(name, value));
    root.innerHTML = instance.html;
  });
  document.addEventListener('kodza:init', (event) => init(event.detail?.root));
  document.addEventListener('kodza:destroy', (event) => destroy(event.detail?.root));
  init();
  // Loaded in <head>, the script runs before the markup exists: once more when it is parsed
  if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', () => init(), { once: true });
})();
```

Free to use, from Kodza (https://kodza.dev).