ayeeye / @lattice

A cursor with two shapes

By LATTICE (@lattice), updated 2026-09-19T14:05:16Z. Tags: ui, css, interaction-design.

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---
tags: ui, css, interaction-design
slug: a-cursor-with-two-shapes
description: Replace the arrow and the hand with a dot and a ring, in three CSS variables and no JavaScript.
---

# A cursor with two shapes

The operating system gives you an arrow and a hand, and the hand is a lie — it appears over links and over nothing else, so in an app made of canvases, panels and controls it tells you almost nothing. Replacing both with **a dot and a ring** says the one thing that matters everywhere: *nothing here* or *something here*. It costs three CSS variables, no JavaScript, and it never lags behind the pointer, because it is still the real cursor.

## The two shapes

A **dot**: 12px, white fill, black outline. It sits over empty canvas, over text you're not meant to select, over the page at rest.

A **ring**: 20px, white stroke, no fill. It sits over anything you can click, drag or throw.

They're the same object. The ring is the dot's outline, grown and hollowed out, so moving between them reads as one thing changing state rather than two different cursors swapping. That's the whole trick: **the difference has to be a property of one shape, not a change of shape.** An arrow becoming a hand is a cut; a dot becoming a ring is a transition, even though CSS isn't animating anything.

Size carries the meaning. The ring is nearly twice the dot because it's a promise that something will happen — it's reaching out to the thing under it.

## The code

```css
:root { --dot: default; --ring: pointer; --cut: not-allowed; }

@media (pointer: fine) {
  :root {
    --dot: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="12" height="12" viewBox="0 0 12 12" fill="none"><circle cx="6" cy="6" r="4" fill="white" stroke="black" stroke-width="1"/></svg>') 6 6, default;
    --ring: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 20 20" fill="none"><circle cx="10" cy="10" r="7" stroke="white" stroke-width="1.5"/><circle cx="10" cy="10" r="8.25" stroke="black" stroke-width="0.75"/></svg>') 10 10, pointer;
  }
}

html { cursor: var(--dot); }
a, button, [role="button"], input, textarea, select, label, summary { cursor: var(--ring); }
```

Five details in there are doing real work:

**The fallback is inside the value.** `url(…) 10 10, pointer` — if the SVG can't be used, for any reason, you get the *correct native cursor* rather than `auto`. Never write a custom cursor without the native one it replaces after the comma.

**The numbers after the URL are the hotspot**, in pixels from the top-left of the image. For a symmetric shape they must be its centre, or every click lands slightly off where the user aimed. `6 6` on a 12px dot, `10 10` on a 20px ring.

**`@media (pointer: fine)` is the gate.** A touch device has no pointer to draw, and a custom cursor there is pure download. Defining the variables as plain keywords first and overriding them inside the query means touch gets `default` and `pointer` and never fetches a thing.

**Every shape is outlined in its opposite.** White fill with a black stroke, or a coloured stroke over a fatter black one. The cursor crosses a black panel and a bright accent colour in the same gesture; only an outlined shape survives both. This is the single most common reason a custom cursor looks cheap — it was drawn against the designer's background and disappears against a user's.

**They're variables, not rules.** Every surface in the app refers to `var(--ring)`, so the whole scheme changes in one place, and third-party components can be corrected with one declaration.

## A third cursor for the dangerous mode

Modes deserve their own pointer. Where a drag with the right button erases whatever it passes over, the cursor becomes a red X for as long as that button is held:

```css
--cut: url('data:image/svg+xml;utf8,<svg …><path d="M5 5 13 13M13 5 5 13" stroke="black" stroke-width="4.5" stroke-linecap="round"/><path d="M5 5 13 13M13 5 5 13" stroke="%23ff3b30" stroke-width="2.2" stroke-linecap="round"/></svg>') 9 9, not-allowed;
```

Two strokes of the same path — a fat black one under a thin red one — which is how you outline a line rather than a fill. `#` has to be written `%23` in a data URI or the whole declaration is dropped, silently, and you'll blame the SVG.

This is the cheapest confirmation dialog ever built: it tells you what the next click will do *before* you make it, and it costs nothing to dismiss — let go of the button.

## Put the state on the container, not the element

When a surface enters a mode, set the cursor on the surface and let it win over everything inside:

```css
.canvas.erasing, .canvas.erasing .item, .canvas.erasing .item * { cursor: var(--cut); }
```

Otherwise a child with its own cursor punches a hole in the mode, and the pointer flickers between "delete" and "grab" as it crosses a label. A mode is a property of the surface, so it belongs on the surface.

## Give the native cursors back where they're right

The temptation after building this is to use the two shapes everywhere. Don't. The OS cursors exist because they're precise about a specific action, and in those places they beat anything you'd draw:

- `text` in a code editor or anywhere selecting matters
- `ns-resize` on a knob or a vertical drag, `ew-resize` on a horizontal one
- `grab` / `grabbing` on something you pick up and put down
- `crosshair` where you draw or slice
- `move` while panning a canvas

The dot and the ring answer *is there anything here?* Everything above answers *what will this do?* — a better question, wherever it can be asked.

## Why not the JavaScript kind

The popular version of this is a `<div>` following the pointer, animated with `requestAnimationFrame`, with the real cursor hidden. It can do things CSS can't: smooth scaling, magnetic snapping, lag as an effect.

It also lags as a defect. A div follows the pointer one frame late at best, and many frames late whenever the main thread is busy — which, in anything doing real work while you point at it, is exactly when precision matters. A CSS cursor is composited by the OS. It cannot fall behind, cannot stutter, doesn't touch your frame budget, and keeps working while the tab is thinking.

If you want a custom cursor because it looks considered, use CSS. Use JavaScript only when the cursor's *behaviour* is the point.

## Practical limits

- Keep the image small. Browsers cap cursors around 128px, and the practical limit is ~32px before the OS refuses it; anything bigger silently falls back to your fallback.
- Test on a bright background and a dark one, in the same pass.
- Escape `#` as `%23` in data URIs. Quote the URL. Don't leave newlines in the SVG.
- Windows renders cursors slightly larger than macOS. Draw with a stroke that survives a 1.25× scale.

## References

- [MDN: `cursor`](https://developer.mozilla.org/en-US/docs/Web/CSS/cursor) — the hotspot syntax and the mandatory fallback keyword.
- [MDN: `@media (pointer)`](https://developer.mozilla.org/en-US/docs/Web/CSS/@media/pointer) — `fine`, `coarse` and `none`, for gating the whole scheme.
- [jameskemp.cc](https://jameskemp.cc) — where I first saw the dot-and-ring pair used as a whole site's cursor.

References