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bracketkit

A headless, pure-CSS tournament bracket for React that actually renders in Safari.

No SVG. No foreignObject. No runtime dependencies. ~4 KB. SSR-safe. Style it any way you like.

npm min+gzip TypeScript license: MIT

🔗 Live demo & docs

The problem

If you've used an SVG-based React bracket library (like @g-loot/react-tournament-brackets or react-tournament-bracket), you've probably hit this in Safari, iOS, or a WebView:

The bracket renders fine in Chrome, but in Safari every match stacks at the top-left (0,0), piled on top of the round headers.

This is a long-standing WebKit bug: SVG <foreignObject> ignores its x/y attributes (and transform) and positions content relative to the top <svg> instead of itself. Libraries that lay matches out as nested <svg>/<foreignObject> therefore collapse to the origin on WebKit — which breaks brackets in Safari, iOS Safari, WKWebView, Capacitor/Cordova apps, and Electron-on-WebKit.

There is no CSS workaround for the SVG approach — x, y, and transform are all ignored on foreignObject in Safari.

bracketkit doesn't use SVG at all. It lays the bracket out with plain flexbox and a few bordered <div>s, so it renders pixel-identically on every engine — Chromium, Firefox, and WebKit.

Why bracketkit

  • 🧩 Headless — bracketkit owns the layout + connector lines; you render the match card. No theme objects to fight, no design lock-in.
  • 🍏 Works everywhere — pure CSS (flexbox + bordered divs). Renders correctly in Safari/iOS/WKWebView/Capacitor where SVG brackets break.
  • 🪶 Tiny & zero-dependency — ~4 KB min+gzip, react as the only peer dependency. ESM + CJS + first-class types.
  • SSR-safe — no useLayoutEffect measurement, no window access; the tree is correct on the first server render.
  • 🎨 Style any way — plain CSS, CSS variables, Tailwind, or the drop-in shadcn/ui component.
  • 📐 Auto-aligned — a round's match always centers on the midpoint of its two feeders, at any size, with no JavaScript measuring.

Comparison

bracketkit @g-loot/react-tournament-brackets react-tournament-bracket react-brackets
Renders correctly in Safari/WebKit ❌ (foreignObject bug) ❌ (SVG) ✅ (CSS)
Rendering tech CSS/flexbox SVG SVG CSS
Headless (bring your own card) ⚠️ partial
Runtime dependencies 0 several several a few
Approx. size (min+gzip) ~4 KB ~30 KB+ ~15 KB+ ~10 KB+
SSR-safe ⚠️ ⚠️
Styling CSS vars / Tailwind / shadcn theme object inline own CSS
TypeScript types ⚠️

Honest note: react-brackets is also CSS-based and renders fine in Safari — bracketkit's edge there is being headless, zero-dependency, smaller, and unopinionated about styling.

Install

npm i bracketkit
# or: pnpm add bracketkit / yarn add bracketkit / bun add bracketkit

Prefer the shadcn/ui workflow? Install a styled, copy-into-your-repo component (you own the code):

npx shadcn@latest add https://hrmasss.github.io/bracketkit/r/bracket.json

Quick start

import { Bracket, type BracketRound } from "bracketkit"

type Team = { name: string; score?: number; won?: boolean }
type Match = { id: string; home: Team; away: Team }

const rounds: BracketRound<Match>[] = [
  {
    id: "qf",
    name: "Quarter-finals",
    matches: [
      { id: "qf1", home: { name: "Lions", score: 2, won: true }, away: { name: "Bears", score: 1 } },
      { id: "qf2", home: { name: "Wolves", score: 0 }, away: { name: "Hawks", score: 3, won: true } },
      // ...
    ],
  },
  { id: "sf", name: "Semi-finals", matches: [/* half as many */] },
  { id: "f", name: "Final", matches: [/* one */] },
]

export function Playoffs() {
  return (
    <div style={{ overflowX: "auto", color: "#cbd5e1" /* sets connector color */ }}>
      <Bracket
        rounds={rounds}
        renderRoundHeader={(r) => <h3>{r.name}</h3>}
        renderMatch={(m) => (
          <div className="my-card">
            <Row team={m.home} />
            <Row team={m.away} />
          </div>
        )}
      />
    </div>
  )
}

That's it — bracketkit positions everything; your renderMatch controls how a match looks.

Theming

bracketkit ships no visual styling beyond the structural layout. Connectors inherit currentColor by default and expose two CSS variables:

[data-bracket-root] {
  --bracket-connector-color: #475569;
  --bracket-connector-width: 2px;
}

Every part also has a stable data-* attribute for styling hooks: data-bracket-root, data-bracket-round, data-bracket-round-header, data-bracket-round-body, data-bracket-match-slot, data-bracket-match, data-bracket-connector (plus data-round-index).

API

<Bracket rounds renderMatch />

Prop Type Default Description
rounds BracketRound<TMatch>[] Rounds left-to-right; each normally has half the matches of the previous.
renderMatch (match, ctx) => ReactNode Renders your match card. ctx = { roundIndex, matchIndex, isFirstRound, isLastRound }.
renderRoundHeader (round, i) => ReactNode round.name Optional column header.
matchWidth number 220 Match column width (px).
connectorWidth number 48 Connector gutter width (px).
matchGap number 12 Minimum vertical gap between matches (px).

All other div props (className, style, …) pass through to the root.

How it works

Each round is a flex column whose matches share equal flex: 1 slots. Because a round has half the matches of the previous one, each match's slot spans exactly two feeder slots — so the two feeders land at 25% and 75% of the slot and the match itself at 50%. The connector elbow is drawn at those same percentages with absolutely-positioned bordered <div>s. The maths is exact at any height, needs zero measurement, and uses no SVG — which is why it survives WebKit.

FAQ

Why does my React tournament bracket render at 0,0 / stacked in Safari? Your library positions matches with SVG <foreignObject>, whose x/y/transform Safari ignores. Switch to a CSS-based bracket like bracketkit, or stop relying on foreignObject positioning.

Does it work with Next.js / SSR / React Server Components? Yes — it's "use client"-free at the layout level and does no DOM measurement, so the markup is correct on the server.

Does it work in Capacitor / Cordova / Electron / iOS WKWebView? Yes — that's the whole point. Those are WebKit, where SVG brackets break and bracketkit doesn't.

Single or double elimination? Single-elimination today. Double-elimination, third-place, and byes are on the roadmap.

Can I use it without Tailwind? Yes — bracketkit is unstyled. Use plain CSS, CSS variables, Tailwind, or the shadcn component — your choice.

Roadmap

  • Double-elimination & third-place playoff
  • Bye / uneven-round handling
  • Right-to-left and top-to-bottom orientations
  • Animated connector + match focus states

License

MIT © hrmasss

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Headless, pure-CSS React tournament bracket that renders correctly in Safari/WebKit — no SVG, no foreignObject. Zero-dependency, SSR-safe, themeable.

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