Are the ai2 Pill buttons free?

Yes. The whole styled layer is free and MIT licensed, like the component core.

Can I change the size?

Yes. Every variation takes a size prop of sm, md, lg or xl, aligned to the base Button height scale.

Pill buttons

Five rounded outlines with different fills: left, center, a vertical swap, an inner-shadow outline and a growing dot. Each is sized and token-driven.

ButtonsPill

Installation

The styled layer is free and installs like any other ai2 component.

Run the following command

npx shadcn@latest add @ai2/buttons-pill

Dependencies, the @ai2/tokens theme and the component file are installed together.

Install dependencies

npm install motion

Copy the source

components/ui/buttons-pill.tsx

"use client"

import type * as React from "react"
import { motion, useReducedMotion, type HTMLMotionProps } from "motion/react"

import { cn } from "@/lib/utils"

/* Pill button family: rounded-full outlines plus different fill methods, 5 variations. All are sized, use a framer-motion tap, take colour ONLY from the primary/foreground tokens (guaranteed contrast in both themes) and are reduced-motion safe. */

export type StyledSize = "sm" | "md" | "lg" | "xl"

const sizes: Record<StyledSize, string> = {
  sm: "h-8 gap-1.5 px-4 text-sm",
  md: "h-9 gap-2 px-5 text-sm",
  lg: "h-10 gap-2 px-6 text-sm",
  xl: "h-12 gap-2.5 px-7 text-base",
}

const base =
  "group relative inline-flex shrink-0 select-none items-center justify-center overflow-hidden rounded-full border border-primary/30 bg-transparent font-medium whitespace-nowrap outline-none focus-visible:ring-[3px] focus-visible:ring-ring/50 disabled:pointer-events-none disabled:opacity-50 [&_svg]:pointer-events-none [&_svg]:size-4 [&_svg]:shrink-0 [&_i]:text-base [&_i]:leading-none"

type Props = HTMLMotionProps<"button"> & { size?: StyledSize }

/* Fill: soldan saga dolan primary yuzey; metin doldukca foreground'a doner. */
export function FillButton({ className, size = "md", children, ...props }: Props) {
  const reduce = useReducedMotion()
  return (
    <motion.button
      data-slot="styled-button"
      whileTap={reduce ? undefined : { scale: 0.96 }}
      transition={{ type: "spring", stiffness: 400, damping: 20 }}
      className={cn(base, sizes[size], "text-foreground transition-colors group-hover:text-primary-foreground hover:text-primary-foreground", className)}
      {...props}
    >
      <span
        aria-hidden="true"
        className="pointer-events-none absolute inset-0 origin-left scale-x-0 rounded-full bg-primary transition-transform duration-(--motion-base) ease-(--motion-ease) group-hover:scale-x-100"
      />
      <span className="relative flex items-center gap-2">{children as React.ReactNode}</span>
    </motion.button>
  )
}

/* Center: the primary surface opens from the center to both sides. */
export function CenterFillButton({ className, size = "md", children, ...props }: Props) {
  const reduce = useReducedMotion()
  return (
    <motion.button
      data-slot="styled-button"
      whileTap={reduce ? undefined : { scale: 0.96 }}
      transition={{ type: "spring", stiffness: 400, damping: 20 }}
      className={cn(base, sizes[size], "text-foreground transition-colors group-hover:text-primary-foreground hover:text-primary-foreground", className)}
      {...props}
    >
      <span
        aria-hidden="true"
        className="pointer-events-none absolute inset-0 origin-center scale-x-0 rounded-full bg-primary transition-transform duration-(--motion-base) ease-(--motion-ease) group-hover:scale-x-100"
      />
      <span className="relative flex items-center gap-2">{children as React.ReactNode}</span>
    </motion.button>
  )
}

/* Swap: the current label slides up on hover and a primary-grounded copy comes from below. */
export function SwapButton({ className, size = "md", children, ...props }: Props) {
  const reduce = useReducedMotion()
  return (
    <motion.button
      data-slot="styled-button"
      whileTap={reduce ? undefined : { scale: 0.96 }}
      transition={{ type: "spring", stiffness: 400, damping: 20 }}
      className={cn(base, sizes[size], "text-foreground", className)}
      {...props}
    >
      <span className="pointer-events-none flex items-center gap-2 opacity-0">{children as React.ReactNode}</span>
      <span className="absolute inset-0 flex items-center justify-center gap-2 transition-transform duration-(--motion-base) ease-(--motion-ease) group-hover:-translate-y-full">
        {children as React.ReactNode}
      </span>
      <span className="absolute inset-0 flex translate-y-full items-center justify-center gap-2 bg-primary text-primary-foreground transition-transform duration-(--motion-base) ease-(--motion-ease) group-hover:translate-y-0">
        {children as React.ReactNode}
      </span>
    </motion.button>
  )
}

/* Outline: stays transparent and fills with an inner primary shadow on hover. */
export function OutlineFillButton({ className, size = "md", children, ...props }: Props) {
  const reduce = useReducedMotion()
  return (
    <motion.button
      data-slot="styled-button"
      whileTap={reduce ? undefined : { scale: 0.96 }}
      transition={{ type: "spring", stiffness: 400, damping: 20 }}
      className={cn(
        base,
        sizes[size],
        "text-foreground transition-[color,box-shadow] duration-(--motion-base) hover:text-primary-foreground hover:shadow-[inset_0_0_0_2.5rem_var(--primary)]",
        className
      )}
      {...props}
    >
      <span className="relative flex items-center gap-2">{children as React.ReactNode}</span>
    </motion.button>
  )
}

/* Dot: the leading primary dot grows on hover until it fills the button. */
export function DotButton({ className, size = "md", children, ...props }: Props) {
  const reduce = useReducedMotion()
  return (
    <motion.button
      data-slot="styled-button"
      whileTap={reduce ? undefined : { scale: 0.96 }}
      transition={{ type: "spring", stiffness: 400, damping: 20 }}
      className={cn(base, sizes[size], "pl-9 text-foreground transition-colors group-hover:text-primary-foreground hover:text-primary-foreground", className)}
      {...props}
    >
      <span
        aria-hidden="true"
        className="pointer-events-none absolute left-3 top-1/2 size-2.5 -translate-y-1/2 origin-left rounded-full bg-primary transition-transform duration-(--motion-slow) ease-(--motion-ease) group-hover:scale-[16]"
      />
      <span className="relative flex items-center gap-2">{children as React.ReactNode}</span>
    </motion.button>
  )
}

Manual installs skip the @ai2/tokens theme, so add the token CSS from the theming guide or the tone colors will be missing.

Variations

5 takes on the same idea. Each is its own export, and every one accepts a size prop (sm, md, lg, xl) aligned to the base Button scale.

Fill

A primary surface fills from the left on hover.

Center

A primary surface opens outward from the center.

Swap

The label slides up and a primary-filled copy rises in.

Outline

A clear outline fills with primary via an inner shadow on hover.

Dot

A leading primary dot grows to fill the button on hover.

ai2 Pill buttons: 5 styled variations on the token system

The ai2 Pill buttons are a set of 5 decorative button variations from the styled layer of the @ai2 design system, built around rounded outlines that fill on hover. They are free and MIT licensed, and every color comes from a semantic token, so they theme with the rest of ai2 in light and dark.

Motion runs on framer-motion: framer-motion adds a spring on tap while the fills run on token transitions. The styled layer is opt-in, so the dependency only lands if you use it; the base components stay lean. Under reduced motion, the tap spring is disabled; the CSS fills still respond to hover.

What is in the ai2 Pill buttons?

5 exports in one file: Fill, Center, Swap, Outline and Dot. Each renders a native button and takes a size prop (sm, md, lg, xl) aligned to the base Button. They are separate from the base Button on purpose: the base keeps its clean variant, tone and size axes, while the styled layer carries the effects.

You own the file. Copy the one category file and you have all 5 variations, with no runtime dependency on ai2 itself.

Why use it

On-system by construction: Every color resolves to an ai2 semantic token, so the buttons follow your theme in light and dark with no extra work.
Effect without the sprawl: The decorations live in a dedicated styled file, so the base Button keeps its clean, predictable API.
Accessible and honest: Each renders a real button element, keeps a visible focus ring, and respects prefers-reduced-motion.

Features

Token-driven color: No hardcoded hex or oklch; the look recolors with your theme tokens.
framer-motion: framer-motion adds a spring on tap while the fills run on token transitions.
Reduced-motion aware: Under prefers-reduced-motion, the tap spring is disabled; the CSS fills still respond to hover.
Size aligned to the base: Every variation takes sm, md, lg and xl matching the base Button height scale, so styled and base buttons line up in a row.

Production tips

Use it for emphasis, not everywhere: Styled buttons draw the eye. Reserve them for the one action you want people to take on a screen, and use the base Button for the rest.
Keep labels as verbs: The decoration adds weight, so a clear action label keeps the button scannable.
Pick one variation per surface: The variations share a family; using two different ones in the same view competes for attention.

Works with the rest of ai2

The Pill buttons sit alongside the base Button and the rest of the @ai2 registry. They share the same token file, so a styled action next to a base button or a badge stays visually consistent in both modes.