# Inner Parallax Image

> A picture that drifts slower than the page inside a frame that stays put. It wraps the image WordPress writes in its own frame, and the picture overhangs by its whole travel, so no gap ever shows.

Scroll · parallax, image, scroll, frame, wordpress, portrait, blog · HTML, CSS, vanilla JS · no dependencies · updated 2026-11-06
Demo: https://kodza.dev/components/inner-parallax-image/
Source on GitHub: https://github.com/kodza-dev/kodza/tree/main/components/inner-parallax-image

Takes the whole screen (or reacts to the page scroll): give it a page, not a small box.

## Files

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

- [`kodza-inner-parallax-image.css`](https://kodza.dev/registry/inner-parallax-image/kodza-inner-parallax-image.css) · 6.4 KB
- [`kodza-inner-parallax-image.js`](https://kodza.dev/registry/inner-parallax-image/kodza-inner-parallax-image.js) · 8.6 KB
- [`kodza-inner-parallax-image.html`](https://kodza.dev/registry/inner-parallax-image/kodza-inner-parallax-image.html) · 0.4 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-inner-parallax-image.css https://kodza.dev/registry/inner-parallax-image/kodza-inner-parallax-image.css
curl -fsSL --create-dirs -o kodza/kodza-inner-parallax-image.js https://kodza.dev/registry/inner-parallax-image/kodza-inner-parallax-image.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`.)

**Its images are free to use in what you ship** (Kodza house images, Kodza License). The HTML loads them from kodza.dev, whose addresses can change: copy them into the project and point each `src` to the copy (a Claude artifact embeds them instead, as Use it says).

```bash
curl -fsSL --create-dirs -o kodza/media/kz-block-1400.webp https://kodza.dev/media/kz-block-1400.webp
```

## API

- Root: `[data-kodza-inner-parallax-image]`
- Variables (set them on the root element itself: it declares its own defaults):
  - `--kz-inner-parallax-image-drift: 0.08`
  - `--kz-inner-parallax-image-radius: calc(16px * var(--kz-radius-scale, 1))`
  - `--kz-inner-parallax-image-caption: color-mix(in srgb, var(--kz-color-ink, #0a0a0a) 62%, transparent)`
  - `--kz-inner-parallax-image-caption-gap: 12px`
  - `--kz-inner-parallax-image-edge: color-mix(in srgb, var(--kz-color-ink, #0a0a0a) 8%, transparent)`
- Attributes:
  - `data-kodza-inner-parallax-image`
- Lifecycle: `kodza:init` / `kodza:destroy` on `document`, with `{ detail: { root } }` to target a container.

## Images

The shape of each image slot, measured in the demo at 1440 × 900 (desktop) and 390 × 844 (mobile). Where the shape is fixed, the frame crops the image to it: export in that shape, keep the subject near the centre, at twice the widest size shown (sharp on retina screens).

| Slot | Desktop | Mobile | Widest shown |
| --- | --- | --- | --- |
| `.kodza-inner-parallax-image__frame img` | any: the frame follows the image | any: the frame follows the image | 1080 px |

## 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-inner-parallax-image {
    --kz-inner-parallax-image-caption: rgba(242, 242, 240, 0.62);
    --kz-inner-parallax-image-edge: rgba(255, 255, 255, 0.12);
  }
}
```

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

Its images have dark versions next to them (`kz-block-1400.webp` → `kz-block-dark-1400.webp`). To swap them on a dark page: `<picture><source media="(prefers-color-scheme: dark)" srcset="…-dark-….webp"><img …></picture>`.

## Use it

### Plain HTML page

- CSS: `kodza/kodza-inner-parallax-image.css` next to the page (the Files commands as they are), linked in `<head>`: `<link rel="stylesheet" href="kodza/kodza-inner-parallax-image.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-inner-parallax-image.js`, loaded with `<script src="kodza/kodza-inner-parallax-image.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. A site with its own type sets it once for every Kodza component, on `:root`, never by editing the CSS (unset, nothing changes): `--kz-font-label`, the face of the small labels (meta, captions, counters, hints, footer links, button labels); `--kz-font-label-size`, their size, one for all of them (`11px`…); `--kz-font-label-weight`, their weight; `--kz-font-label-tracking`, their letter-spacing; `--kz-font-label-case`, their case (`uppercase`…; code and units keep theirs); `--kz-font-label-leading`, their line-height (`1.45`…; buttons, pills and keys keep their box); `--kz-font-mono`, the monospace face (code, labels, counters). 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">`.
- Corners: a site with its own shapes sets them once for every Kodza component, on `:root`, never by editing the CSS (unset, nothing changes): `--kz-radius-scale` multiplies every corner (`0` square, `0.5` softer, `1` Kodza).
- Motion: a site sets its pace once for every Kodza component, on `:root`, never by editing the CSS or the JS: `--kz-motion-scale` multiplies every duration (`0.5` twice as fast, `2` twice as slow, `0` no motion at all, loops stopped, like reduced motion). Unset, nothing changes.
- 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$/{r kodza/kodza-inner-parallax-image.css' -e 'd' -e '}' -e '/^KODZA-JS$/{r kodza/kodza-inner-parallax-image.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">`. A site with its own type sets it once for every Kodza component, on `:root`, never by editing the CSS (unset, nothing changes): `--kz-font-label`, the face of the small labels (meta, captions, counters, hints, footer links, button labels); `--kz-font-label-size`, their size, one for all of them (`11px`…); `--kz-font-label-weight`, their weight; `--kz-font-label-tracking`, their letter-spacing; `--kz-font-label-case`, their case (`uppercase`…; code and units keep theirs); `--kz-font-label-leading`, their line-height (`1.45`…; buttons, pills and keys keep their box); `--kz-font-mono`, the monospace face (code, labels, counters).
- Corners: a site with its own shapes sets them once for every Kodza component, on `:root`, never by editing the CSS (unset, nothing changes): `--kz-radius-scale` multiplies every corner (`0` square, `0.5` softer, `1` Kodza).
- Motion: a site sets its pace once for every Kodza component, on `:root`, never by editing the CSS or the JS: `--kz-motion-scale` multiplies every duration (`0.5` twice as fast, `2` twice as slow, `0` no motion at all, loops stopped, like reduced motion). Unset, nothing changes.
- Images: the artifact blocks every other host, `kodza.dev` included, without an error. Embed each one as a `data:` URI, with a command if you can run one (`curl -s <url> | base64`; the 1400 px files weigh 10 to 30 KB), never by typing base64 out. If you can't run commands, keep the `<img>` with its `width` and `height`, and tell the user the picture stays blank inside the artifact.
- 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.
- 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-inner-parallax-image', $uri . 'kodza-inner-parallax-image.css', [], filemtime($dir . 'kodza-inner-parallax-image.css'));
    wp_enqueue_script('kodza-inner-parallax-image', $uri . 'kodza-inner-parallax-image.js', [], filemtime($dir . 'kodza-inner-parallax-image.js'), true);
  });
  ```
  Scoped to `kodza-` classes, the CSS never touches the theme. One copy of the JS, whatever the number of blocks.
- No access to the theme files? The CSS can also go, as it is, in **Appearance → Customize → Additional CSS** (classic theme) or **Styles → Additional CSS** in the Site Editor (block theme).
- 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-inner-parallax-image.css` and `assets/kodza-inner-parallax-image.js` (the Files commands with `-o assets/…`).
- In the section: `{{ 'kodza-inner-parallax-image.css' | asset_url | stylesheet_tag }}` and `<script src="{{ 'kodza-inner-parallax-image.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/`): `InnerParallaxImage.tsx` (below), the CSS block under Code saved as `inner-parallax-image.css` and the JS block as `inner-parallax-image.js`, both as they are. The HTML block is already inside the component: skip it.
- Use it: `import { InnerParallaxImage } from '@/components/kodza/InnerParallaxImage';` then `<InnerParallaxImage>Slab 04 — Le Havre, 2026</InnerParallaxImage>`. Props: `vars` (the `--kz-…` variables listed under API, e.g. `vars={{ '--kz-inner-parallax-image-drift': … }}`), `children` (the text, plain), `className`, `style` and the other props of its `<figure>` (`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 './inner-parallax-image.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.
- Built from your data (tabs, rows, options)? Add what the markup is made of to the `key`, as plain values (ids, text, numbers). What the visitor changes (the open tab, the sort, what they type) is the script's: follow it with `onClick` or `onInput` on the root, and change it from your code as a visitor would (click the tab; set the field's value, then dispatch a bubbling `input` event). Fields stay uncontrolled (`defaultValue`, `name`).

```tsx
'use client';
// Kodza — Inner Parallax Image, for React. From https://kodza.dev/components/inner-parallax-image/
// 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: inner-parallax-image.css and inner-parallax-image.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.
// data-kodza-manual keeps the script from starting it on its own: the effect below does, once
// React has hydrated the markup (on a page that streams in, the script can load first).
// Built from your data (tabs, rows, options)? Put what the markup is made of in the key, as plain
// values (ids, text, numbers): a change starts the script again on fresh markup. What the visitor
// changes (the open tab, the sort, what they type) is the script's: keep it out of the key, follow
// it with onClick or onInput on the root, and change it from your code as a visitor would (click
// the tab; set the field's value, then dispatch a bubbling input event).
import { useRef, useEffect, type ComponentPropsWithoutRef, type ComponentRef, type CSSProperties } from 'react';
import './inner-parallax-image.css';

export type InnerParallaxImageProps = Omit<ComponentPropsWithoutRef<'figure'>, "children" | "vars"> & {
  /** Settings, as CSS variables on the root */
  vars?: {
    /** default: 0.08 */
    "--kz-inner-parallax-image-drift"?: string | number;
    /** default: calc(16px * var(--kz-radius-scale, 1)) */
    "--kz-inner-parallax-image-radius"?: string | number;
    /** default: color-mix(in srgb, var(--kz-color-ink, #0a0a0a) 62%, transparent) */
    "--kz-inner-parallax-image-caption"?: string | number;
    /** default: 12px */
    "--kz-inner-parallax-image-caption-gap"?: string | number;
    /** default: color-mix(in srgb, var(--kz-color-ink, #0a0a0a) 8%, transparent) */
    "--kz-inner-parallax-image-edge"?: string | number;
  };
  /** The text, plain: the script reads it and rebuilds the markup around it */
  children?: string;
  className?: string;
};

export function InnerParallaxImage({ vars, children = "Slab 04 — Le Havre, 2026", className, style, ...rest }: InnerParallaxImageProps) {
  const ref = useRef<ComponentRef<'figure'>>(null);
  const classes = ["kodza-inner-parallax-image", 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('./inner-parallax-image.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 (
    <figure data-kodza-inner-parallax-image="" key={key} {...rest} className={classes} data-kodza-manual style={{ ...vars, ...style } as CSSProperties} ref={ref}>
      <img src="https://kodza.dev/media/kz-block-1400.webp" alt="A tall concrete slab standing alone, its long shadow stretching toward the viewer" width="1120" height="1400" loading="lazy" />
      <figcaption className="kodza-inner-parallax-image__caption">{children}</figcaption>
    </figure>
  );
}
```

## Code

```html
<figure class="kodza-inner-parallax-image" data-kodza-inner-parallax-image>
  <img src="https://kodza.dev/media/kz-block-1400.webp" alt="A tall concrete slab standing alone, its long shadow stretching toward the viewer" width="1120" height="1400" loading="lazy">
  <figcaption class="kodza-inner-parallax-image__caption">Slab 04 — Le Havre, 2026</figcaption>
</figure>
```

```css
/* Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license */
/* Kodza — Inner Parallax Image
   A picture that drifts slower than the page inside a frame that stays put. The script wraps the
   picture (the img WordPress writes) in its own frame and moves it a share of the frame's height,
   from the frame entering at the bottom of the screen to it leaving at the top: the picture
   overhangs by its whole travel, so no gap ever shows.
   Tuned with the --kz-inner-parallax-image-* variables; the smoothing is a constant at the top
   of component.js. */
.kodza-inner-parallax-image {
  /* How far the picture travels each way, as a share of the frame's height. 0.08 is seen without
     getting in the way (0.06 is barely there); a negative value moves it with the scroll */
  --kz-inner-parallax-image-drift: 0.08;
  /* The frame's corners */
  --kz-inner-parallax-image-radius: calc(16px * var(--kz-radius-scale, 1));
  /* The caption under the frame */
  --kz-inner-parallax-image-caption: color-mix(in srgb, var(--kz-color-ink, #0a0a0a) 62%, transparent);
  --kz-inner-parallax-image-caption-gap: 12px;
  /* A 1px line inside the frame's edge, so a dark picture keeps its corners on a dark page */
  --kz-inner-parallax-image-edge: color-mix(in srgb, var(--kz-color-ink, #0a0a0a) 8%, transparent);

  display: block;
  margin: 0;
}

/* Laid by the script around the picture: without it, the page shows the picture as it is */
.kodza-inner-parallax-image__frame {
  position: relative;
  display: block;
  overflow: hidden;
  border-radius: var(--kz-inner-parallax-image-radius);
  /* Its own layer, so the moving picture stays clipped to the round corners (Safari) */
  isolation: isolate;
  transform: translateZ(0);
}

.kodza-inner-parallax-image__frame::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  border-radius: inherit;
  box-shadow: inset 0 0 0 1px var(--kz-inner-parallax-image-edge);
  pointer-events: none;
}

.kodza-inner-parallax-image__frame img {
  display: block;
  width: 100%;
  max-width: none;
  height: auto;
  margin: 0;
  border-radius: 0;
  backface-visibility: hidden;
}

/* Only while it is on screen and moving */
.kodza-inner-parallax-image.is-moving .kodza-inner-parallax-image__frame img {
  will-change: transform;
}

.kodza-inner-parallax-image__caption {
  margin: var(--kz-inner-parallax-image-caption-gap) 0 0;
  font-family: var(--kz-font-label, var(--kz-font-mono, "Geist Mono", ui-monospace, "SF Mono", Menlo, monospace));
  font-size: var(--kz-font-label-size, 12px);
  font-weight: var(--kz-font-label-weight, 400);
  line-height: var(--kz-font-label-leading, 1.4);
  letter-spacing: var(--kz-font-label-tracking, normal);
  text-transform: var(--kz-font-label-case, none);
  color: var(--kz-inner-parallax-image-caption);
}

/* kodza-guard 5d54bb21ad5b — 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-inner-parallax-image:not(#_) {
  border: revert;
  padding: revert;
  border-radius: revert;
  outline: revert;
  text-decoration: revert;
  transition: revert;
  list-style: revert;
  box-sizing: revert;
  position: revert;
  background-color: revert;
  background-image: revert;
  box-shadow: revert;
  outline-offset: revert;
  appearance: revert;
  max-height: revert;
  color: revert;
  font-family: revert;
  font-size: revert;
  font-weight: revert;
  font-style: revert;
  line-height: revert;
  letter-spacing: revert;
  text-transform: revert;
  text-underline-offset: revert;
  text-align: revert;
  text-indent: revert;
  text-shadow: revert;
  vertical-align: revert;
}

.kodza-inner-parallax-image__frame:not(#_) {
  box-sizing: revert;
}

.kodza-inner-parallax-image__caption:not(#_) {
  border: revert;
  padding: revert;
  border-radius: revert;
  outline: revert;
  text-decoration: revert;
  transition: revert;
  list-style: revert;
  box-sizing: revert;
  float: revert;
  position: revert;
  background-color: revert;
  background-image: revert;
  box-shadow: revert;
  outline-offset: revert;
  appearance: revert;
  max-width: revert;
  max-height: revert;
  font-style: revert;
  text-underline-offset: revert;
  text-align: revert;
  text-indent: revert;
  text-shadow: revert;
  vertical-align: revert;
}

.kodza-inner-parallax-image__frame img:where(:not([class*="kodza-"])):not(#_) {
  border: revert;
  padding: revert;
  outline: revert;
  text-decoration: revert;
  transition: revert;
  list-style: revert;
  box-sizing: revert;
  float: revert;
  position: revert;
  background-color: revert;
  background-image: revert;
  box-shadow: revert;
  outline-offset: revert;
  appearance: revert;
  max-height: revert;
  color: revert;
  font-family: revert;
  font-size: revert;
  font-weight: revert;
  font-style: revert;
  line-height: revert;
  letter-spacing: revert;
  text-transform: revert;
  text-underline-offset: revert;
  text-align: revert;
  text-indent: revert;
  text-shadow: revert;
  vertical-align: revert;
}

.kodza-inner-parallax-image__caption:not(#_):where(:not([hidden])) {
  display: revert;
}

.kodza-inner-parallax-image__caption:not(#_):where([hidden]) {
  display: none;
}

.kodza-inner-parallax-image__frame:not(#_)::after {
  box-sizing: revert;
}

/* The component's own rules, one step stronger: real buttons and fields, what it sets on tags themes style (links, lists, headings, images…), and the root width (a theme may narrow it, never widen it) */

.kodza-inner-parallax-image:not(#_) {
  display: block;
}

.kodza-inner-parallax-image__frame img:not(#_) {
  display: block;
  max-width: none;
  margin: 0;
  border-radius: 0;
}

.kodza-inner-parallax-image__caption:not(#_) {
  margin: var(--kz-inner-parallax-image-caption-gap) 0 0;
  font-family: var(--kz-font-label, var(--kz-font-mono, "Geist Mono", ui-monospace, "SF Mono", Menlo, monospace));
  font-size: var(--kz-font-label-size, 12px);
  font-weight: var(--kz-font-label-weight, 400);
  line-height: var(--kz-font-label-leading, 1.4);
  letter-spacing: var(--kz-font-label-tracking, normal);
  text-transform: var(--kz-font-label-case, none);
  color: var(--kz-inner-parallax-image-caption);
}
```

```js
// Kodza License: free to use, client work included. Not to resell or redistribute, ported or not: https://kodza.dev/docs/#print-license
// Kodza — Inner Parallax Image
// Wraps the picture in its own frame, then moves it a share of the frame's height as the frame
// crosses the screen: from the frame entering at the bottom to it leaving at the top. The picture
// is zoomed by its whole travel, so its edges never show. Reduced motion, or a site pace of 0:
// the frame is laid, nothing moves. The drift is --kz-inner-parallax-image-drift (component.css),
// the smoothing just below.
(() => {
  const SELECTOR = '[data-kodza-inner-parallax-image]';
  // How long the picture takes to catch up with the scroll, in ms (times the site's pace): a soft
  // follow instead of a picture glued to the wheel. 0 glues it
  const SMOOTHING = 110;
  // The picture's own move left below this, in px, ends the loop
  const SETTLE = 0.05;

  const reduceMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
  // The site's pace, --kz-motion-scale (set on :root, read on the instance): every duration of the
  // script times it, and 0 moves nothing, like reduced motion
  const paceOf = (el) => {
    const pace = parseFloat(getComputedStyle(el).getPropertyValue('--kz-motion-scale'));
    return pace >= 0 ? pace : 1;
  };
  const clamp = (value, min, max) => Math.min(max, Math.max(min, value));

  // One instance, with its own state: two copies on a page never interfere. Everything it
  // starts is tied to `signal` (listeners get { signal }, observers and timers stop on its
  // 'abort' event), so kodza:destroy stops it all.
  function mount(root, signal) {
    const img = root.querySelector('img');
    if (!img) return;
    // The frame goes around the picture itself (or its <picture>), inside a link if there is one,
    // and leaves the caption out
    const target = img.closest('picture') && root.contains(img.closest('picture')) ? img.closest('picture') : img;
    const frame = document.createElement('span');
    frame.className = 'kodza-inner-parallax-image__frame';
    target.replaceWith(frame);
    frame.append(target);

    const pace = paceOf(root);
    const still = reduceMotion || !pace; // the still path: no motion asked, by the visitor or the site
    if (still) return;
    const drift = parseFloat(getComputedStyle(root).getPropertyValue('--kz-inner-parallax-image-drift')) || 0;
    if (!drift) return;
    const zoom = 1 + 2 * Math.abs(drift);
    const smoothing = SMOOTHING * pace;

    let current = null; // the picture's offset now, in px of the frame
    let raf = 0;
    let last = 0;
    let shown = false;

    // Where the picture should be: -drift at the bottom of the screen, +drift at the top. Read in px
    // of the screen, written in px of the frame (a parent zoomed by transform must not shift it)
    const goal = () => {
      const rect = frame.getBoundingClientRect();
      const height = frame.offsetHeight;
      if (!height) return 0;
      const progress = clamp((innerHeight - rect.top) / (innerHeight + rect.height), 0, 1);
      return (progress - 0.5) * 2 * drift * height;
    };
    const write = () => {
      img.style.transform = `translate3d(0, ${current.toFixed(2)}px, 0) scale(${zoom})`;
    };
    const tick = (now) => {
      raf = 0;
      const to = goal();
      const step = last ? Math.min(now - last, 64) : 16.7;
      last = now;
      if (current === null || !smoothing) current = to;
      else current += (to - current) * (1 - Math.exp(-step / smoothing));
      if (Math.abs(to - current) < SETTLE) current = to;
      write();
      if (current !== to) raf = requestAnimationFrame(tick);
      else last = 0;
    };
    const queue = () => {
      if (!shown || raf) return;
      raf = requestAnimationFrame(tick);
    };

    // Placed before it first shows, so it never slides in from the middle
    current = goal();
    write();
    root.classList.add('is-moving');

    const io = new IntersectionObserver(([entry]) => {
      shown = entry.isIntersecting;
      if (shown) {
        current = goal(); // back on screen after a jump (an anchor, Home): placed, not chased
        write();
        queue();
      }
    });
    io.observe(frame);
    // The frame's height decides the travel: a picture that loads late, a new column width
    const resize = new ResizeObserver(queue);
    resize.observe(frame);
    window.addEventListener('scroll', queue, { passive: true, signal });
    window.addEventListener('resize', queue, { signal });
    signal.addEventListener('abort', () => {
      io.disconnect();
      resize.disconnect();
      cancelAnimationFrame(raf);
    });
  }

  // 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. Each running root
  // keeps its markup as written under KODZA, shared by every Kodza script on the page: a Kodza
  // component inside another one is saved as written, not half-started, and stopped with it. Two
  // components on one root (a reveal on a stat card) both start, and stop together.
  const KODZA = Symbol.for('kodza');
  const RUNNING = Symbol.for(`kodza ${SELECTOR}`); // a root this component runs on, for every copy of this script
  const instances = new WeakMap();
  const find = (scope = document) => [scope, ...scope.querySelectorAll(SELECTOR)].filter((el) => el.matches?.(SELECTOR));
  const attrsOf = (el) => [...el.attributes].map((a) => [a.name, a.value]);
  const put = (el, saved) => {
    [...el.attributes].forEach((a) => el.removeAttribute(a.name));
    saved.attrs.forEach(([name, value]) => el.setAttribute(name, value));
    el.innerHTML = saved.html;
  };
  // The markup inside a root as written: Kodza components already running in it give back their own
  const written = (root) => {
    const all = [...root.querySelectorAll('*')];
    if (!all.some((el) => el[KODZA])) return root.innerHTML;
    const copy = root.cloneNode(true);
    const twins = copy.querySelectorAll('*');
    let last = null;
    all.forEach((el, i) => {
      if (!el[KODZA] || last?.contains(el)) return;
      last = el;
      put(twins[i], el[KODZA]);
    });
    return copy.innerHTML;
  };
  const init = (scope) => find(scope).forEach((root) => {
    // Already running, maybe from another copy of this script. Marked is-ready with no Kodza component
    // running on it, a root is a copy of a started one (a cloned slide): it is left as it is
    if (root[RUNNING] || (root.classList.contains('is-ready') && !root[KODZA])) return;
    // Rendered by React (data-kodza-manual): React starts it, with an init aimed at that markup once
    // it has hydrated it. Any earlier start would change markup React has not taken over yet
    const owner = root.closest('[data-kodza-manual]');
    if (owner && !(scope && owner.contains(scope))) return;
    const controller = new AbortController();
    // Another Kodza component already running on this root: its markup as written is kept, and the
    // two stop together
    const before = root[KODZA];
    const saved = { html: before ? before.html : written(root), attrs: before ? before.attrs : attrsOf(root), stop: () => destroy(root) };
    if (before) before.above = saved;
    instances.set(root, { controller, saved, before });
    root[KODZA] = saved;
    root[RUNNING] = true;
    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.saved.above?.stop(); // a Kodza component started after it on the same root stops first
    // The Kodza components running inside it stop first: once its markup is put back, their own
    // script could not find them any more
    root.querySelectorAll('*').forEach((el) => el[KODZA]?.stop());
    instance.controller.abort();
    delete root[RUNNING];
    // Started on top of another one: that one stops next, and puts the markup back
    if (instance.before) {
      delete instance.before.above;
      root[KODZA] = instance.before;
      return instance.before.stop();
    }
    delete root[KODZA];
    put(root, instance.saved);
  });
  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).