# Tabs with a hover-following pill

> A soft pill chases your cursor across the tabs and drifts back to the active one when you leave.

- Category: [Filters](https://library.aimran.es/components/filters)
- Built with: HTML + CSS
- Live editor: https://library.aimran.es/blocks/uv-f-tabs-follow
- Library: AIMRAN Library (https://library.aimran.es), free, no sign-up, by Aimran Oukham

## Where to use it

This works well on desktop pages where people browse before they commit. Say, an events site with Popular, New, Nearby and Top this week, or a template marketplace. The pill previews where a click would land, which makes the row feel responsive even before anyone clicks. Often searched as hover tabs or a magic line navigation.

On touch screens there is no hover, so the pill simply jumps to the tapped tab. That is fine, but don't count on the effect for a mobile-first app. Keep the tint light; it should hint, not highlight.

## Code

### HTML

```html
<div class="uv-ftf"><span class="p"></span><button class="on">Popular</button><button>New</button><button>Nearby</button><button>Top</button></div>
```

### CSS

```css
.uv-ftf {
  --c1: #0071e3;
  --c2: #8ec5ff;
  --s: 16px;
  /* tamaño */
  --k: 1;
  /* velocidad */
  --fg: #1d1d1f;
  /* texto */
  --bg: #f5f5f7;
  /* fondo */
}

.uv-ftf {
  font-family: -apple-system,BlinkMacSystemFont,"SF Pro Text","Inter",system-ui,sans-serif;
  font-size: var(--s);
  color: var(--fg);
  -webkit-tap-highlight-color: transparent;
  position: relative;
  display: inline-flex;
  gap: .1em;
  padding: .35em;
  border-radius: 999px;
  box-shadow: inset 0 0 0 1.5px color-mix(in srgb,var(--fg) 10%,transparent);
}

.uv-ftf button {
  font-family: -apple-system,BlinkMacSystemFont,"SF Pro Text","Inter",system-ui,sans-serif;
  font-size: var(--s);
  font-weight: 550;
  line-height: 1;
  padding: .72em 1.25em;
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  background: transparent;
  color: var(--fg);
  position: relative;
  transition: color calc(0.32s / var(--k)) cubic-bezier(.25,.1,.25,1),transform calc(0.32s / var(--k)) cubic-bezier(.34,1.56,.64,1);
  z-index: 1;
  font-weight: 600;
}

.uv-ftf button.on {
  color: var(--c1);
}

.uv-ftf .p {
  position: absolute;
  top: .35em;
  left: 0;
  height: calc(100% - .7em);
  border-radius: 999px;
  background: color-mix(in srgb,var(--c1) 14%,transparent);
  transition: transform calc(0.38s / var(--k)) cubic-bezier(.25,.1,.25,1),width calc(0.38s / var(--k)) cubic-bezier(.25,.1,.25,1),opacity calc(0.3s / var(--k)) cubic-bezier(.25,.1,.25,1);
}
```

### JavaScript

```js
document.querySelectorAll(".uv-ftf").forEach(el => {
  const p=el.querySelector(".p"),bs=[...el.querySelectorAll("button")];const mv=b=>{p.style.width=b.offsetWidth+"px";p.style.transform="translateX("+b.offsetLeft+"px)"};let cur=bs[0];bs.forEach(b=>{b.addEventListener("pointerenter",()=>mv(b));b.addEventListener("click",()=>{bs.forEach(x=>x.classList.remove("on"));b.classList.add("on");cur=b})});el.addEventListener("pointerleave",()=>mv(cur));requestAnimationFrame(()=>mv(cur))
});
```

### React

```tsx
// @ts-nocheck: setup() es JavaScript del DOM sin tipos, el mismo de la pestaña JS.
import { useEffect, useRef, type CSSProperties } from "react";

const css = `
.uv-ftf {
  font-family: -apple-system,BlinkMacSystemFont,"SF Pro Text","Inter",system-ui,sans-serif;
  font-size: var(--s);
  color: var(--fg);
  -webkit-tap-highlight-color: transparent;
  position: relative;
  display: inline-flex;
  gap: .1em;
  padding: .35em;
  border-radius: 999px;
  box-shadow: inset 0 0 0 1.5px color-mix(in srgb,var(--fg) 10%,transparent);
}

.uv-ftf button {
  font-family: -apple-system,BlinkMacSystemFont,"SF Pro Text","Inter",system-ui,sans-serif;
  font-size: var(--s);
  font-weight: 550;
  line-height: 1;
  padding: .72em 1.25em;
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  background: transparent;
  color: var(--fg);
  position: relative;
  transition: color calc(0.32s / var(--k)) cubic-bezier(.25,.1,.25,1),transform calc(0.32s / var(--k)) cubic-bezier(.34,1.56,.64,1);
  z-index: 1;
  font-weight: 600;
}

.uv-ftf button.on {
  color: var(--c1);
}

.uv-ftf .p {
  position: absolute;
  top: .35em;
  left: 0;
  height: calc(100% - .7em);
  border-radius: 999px;
  background: color-mix(in srgb,var(--c1) 14%,transparent);
  transition: transform calc(0.38s / var(--k)) cubic-bezier(.25,.1,.25,1),width calc(0.38s / var(--k)) cubic-bezier(.25,.1,.25,1),opacity calc(0.3s / var(--k)) cubic-bezier(.25,.1,.25,1);
}
`;

// Interacción en JavaScript del DOM: la misma que en la pestaña JS.
// eslint-disable-next-line @typescript-eslint/no-explicit-any
function setup(el: any) {
  const p=el.querySelector(".p"),bs=[...el.querySelectorAll("button")];const mv=b=>{p.style.width=b.offsetWidth+"px";p.style.transform="translateX("+b.offsetLeft+"px)"};let cur=bs[0];bs.forEach(b=>{b.addEventListener("pointerenter",()=>mv(b));b.addEventListener("click",()=>{bs.forEach(x=>x.classList.remove("on"));b.classList.add("on");cur=b})});el.addEventListener("pointerleave",()=>mv(cur));requestAnimationFrame(()=>mv(cur))
}

export default function FTabsFollow() {
  const ref = useRef<HTMLDivElement>(null);

  useEffect(() => {
    const el = ref.current?.firstElementChild;
    return el ? setup(el) : undefined;
  }, []);

  return (
    <>
      <style>{css}</style>
      <div
        ref={ref} style={{
          "--c1": "#0071e3",
          "--c2": "#8ec5ff",
          "--s": "16px",
          "--k": "1",
          "--fg": "#1d1d1f",
          "--bg": "#f5f5f7",
        } as CSSProperties}
      >
        <div className="uv-ftf"><span className="p"></span><button className="on">Popular</button><button>New</button><button>Nearby</button><button>Top</button></div>
      </div>
    </>
  );
}
```

## Prompt for AI assistants

Paste this into ChatGPT, Claude, Cursor, v0 or Lovable to adapt the block to your stack (Tailwind, Vue, Svelte…):

````text
I want to add the “Tabs with a hover-following pill” block (Filters) from AIMRAN Library to my project.

## What it is
A soft pill chases your cursor across the tabs and drifts back to the active one when you leave.

## Chosen settings
- Main color: #0071e3
- Secondary color: #8ec5ff
- Size: 16px (from 12 to 24px)
- Speed: 1x (from 0.5 to 2x)

## What I need
1. Add it to my project with the same look and animation as the reference code: same sizes, colours, radii, shadows, timings and easing.
2. It is built with plain HTML and CSS (the reference wraps it in a React component with its CSS). If my project uses something else (Vue, Svelte, Astro, plain HTML…), translate it without losing any behaviour. If I use Tailwind, turn the styles into classes; if not, keep the CSS in its own file.
3. Expose the settings above as props (or CSS variables) with those values as defaults.
4. Make it work well on phones: nothing that depends only on hover, touch targets of at least 44 px and no overflow on 320 px screens.
5. Make it look right in light and dark mode.
6. Keep it accessible: semantic HTML, roles and aria-* where needed, visible focus and keyboard support.
7. Respect prefers-reduced-motion: with reduced motion, no big animations but the same end result.

## Reference code
```tsx
// @ts-nocheck: setup() es JavaScript del DOM sin tipos, el mismo de la pestaña JS.
import { useEffect, useRef, type CSSProperties } from "react";

const css = `
.uv-ftf {
  font-family: -apple-system,BlinkMacSystemFont,"SF Pro Text","Inter",system-ui,sans-serif;
  font-size: var(--s);
  color: var(--fg);
  -webkit-tap-highlight-color: transparent;
  position: relative;
  display: inline-flex;
  gap: .1em;
  padding: .35em;
  border-radius: 999px;
  box-shadow: inset 0 0 0 1.5px color-mix(in srgb,var(--fg) 10%,transparent);
}

.uv-ftf button {
  font-family: -apple-system,BlinkMacSystemFont,"SF Pro Text","Inter",system-ui,sans-serif;
  font-size: var(--s);
  font-weight: 550;
  line-height: 1;
  padding: .72em 1.25em;
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  background: transparent;
  color: var(--fg);
  position: relative;
  transition: color calc(0.32s / var(--k)) cubic-bezier(.25,.1,.25,1),transform calc(0.32s / var(--k)) cubic-bezier(.34,1.56,.64,1);
  z-index: 1;
  font-weight: 600;
}

.uv-ftf button.on {
  color: var(--c1);
}

.uv-ftf .p {
  position: absolute;
  top: .35em;
  left: 0;
  height: calc(100% - .7em);
  border-radius: 999px;
  background: color-mix(in srgb,var(--c1) 14%,transparent);
  transition: transform calc(0.38s / var(--k)) cubic-bezier(.25,.1,.25,1),width calc(0.38s / var(--k)) cubic-bezier(.25,.1,.25,1),opacity calc(0.3s / var(--k)) cubic-bezier(.25,.1,.25,1);
}
`;

// Interacción en JavaScript del DOM: la misma que en la pestaña JS.
// eslint-disable-next-line @typescript-eslint/no-explicit-any
function setup(el: any) {
  const p=el.querySelector(".p"),bs=[...el.querySelectorAll("button")];const mv=b=>{p.style.width=b.offsetWidth+"px";p.style.transform="translateX("+b.offsetLeft+"px)"};let cur=bs[0];bs.forEach(b=>{b.addEventListener("pointerenter",()=>mv(b));b.addEventListener("click",()=>{bs.forEach(x=>x.classList.remove("on"));b.classList.add("on");cur=b})});el.addEventListener("pointerleave",()=>mv(cur));requestAnimationFrame(()=>mv(cur))
}

export default function FTabsFollow() {
  const ref = useRef<HTMLDivElement>(null);

  useEffect(() => {
    const el = ref.current?.firstElementChild;
    return el ? setup(el) : undefined;
  }, []);

  return (
    <>
      <style>{css}</style>
      <div
        ref={ref} style={{
          "--c1": "#0071e3",
          "--c2": "#8ec5ff",
          "--s": "16px",
          "--k": "1",
          "--fg": "#1d1d1f",
          "--bg": "#f5f5f7",
        } as CSSProperties}
      >
        <div className="uv-ftf"><span className="p"></span><button className="on">Popular</button><button>New</button><button>Nearby</button><button>Top</button></div>
      </div>
    </>
  );
}
```

Give me the complete final code, ready to paste, and tell me in one line where to put it in my project.
````