{/* dark brick wall */}

{/* light spill from the tubes onto the wall */}

{GASES.map((g, i) => ( ))}

Hover a letter — it flickers.

); } ``` ## Accessibility & performance Honors `prefers-reduced-motion` with a designed static frame or fade (never a blank box) and passes `className` through. ## Source (`argon.tsx`) ```tsx "use client"; import * as React from "react"; import { cn } from "@/lib/utils"; import { useReducedMotion } from "@/hooks/use-reduced-motion"; /** Built-in gas presets, or any CSS color string. */ export type ArgonGas = "neon" | "argon" | "mercury" | (string & {}); export interface ArgonHandle { /** Switch every tube off and run the ignition intro again. */ replay(): void; /** Destabilise one glyph (by index among visible glyphs), or a seeded random one. */ flicker(index?: number): void; } export interface ArgonProps extends Omit, "children"> { /** The lettering. Use "\n" for a stacked multi-line sign. @default "Open late" */ text?: string; /** Gas fill: "neon" (red-orange), "argon" (ice blue), "mercury" (cold white), or any CSS color. @default "argon" */ gas?: ArgonGas; /** Element the (visually hidden) real text is rendered as, so it stays a heading. @default "h2" */ as?: "h1" | "h2" | "h3" | "p"; /** Glyph size in px at natural size; the sign scales down to fit its container. @default 96 */ fontSize?: number; /** Lit tube stroke width in px at natural size. @default 2.4 */ strokeWidth?: number; /** Render mounting clips beneath each glyph and a back-wire behind every line. @default true */ clips?: boolean; /** Wait until the sign scrolls into view before igniting (otherwise ignite on mount). @default true */ igniteOnView?: boolean; /** Glow strength: bloom size/opacity and interior gas fill. 0–2. @default 1 */ intensity?: number; /** When no pointer has been present for ~1.5s, glyphs occasionally destabilise on their own. @default true */ idle?: boolean; /** Hold the sign fully lit and steady — no intro, hum, or flicker. @default false */ paused?: boolean; /** Imperative handle: `replay()` and `flicker(index?)`. */ ref?: React.Ref; } const GAS_PRESETS: Record = { neon: "#ff5a3c", argon: "#7cc4ff", mercury: "#e8f1ff", }; /** Stagger between glyph ignitions (ms). */ const STAGGER = 70; /** Time for the ignition to travel the dash window (ms). */ const DRAW_MS = 1400; /** Dash window, in em — longer than any glyph's outline. */ const DASH_EM = 10; /** Photosensitivity budget: max opacity dips from hover/idle flicker in any 1s window. */ const MAX_DIPS_PER_SECOND = 3; const FLICKER_DIPS = 2; interface Glyph { char: string; line: number; /** Start x relative to the line's left edge. */ x: number; /** Advance width. */ w: number; } interface Layout { glyphs: Glyph[]; lineWidths: number[]; measured: boolean; } function mulberry32(seed: number) { let a = seed >>> 0; return () => { a = (a + 0x6d2b79f5) >>> 0; let t = a; t = Math.imul(t ^ (t >>> 15), t | 1); t ^= t + Math.imul(t ^ (t >>> 7), t | 61); return ((t ^ (t >>> 14)) >>> 0) / 4294967296; }; } function hashString(s: string): number { let h = 2166136261; for (let i = 0; i < s.length; i++) { h ^= s.charCodeAt(i); h = Math.imul(h, 16777619); } return h >>> 0; } /** Deterministic pre-measure layout (SSR + first client render; hidden until measured). */ function estimateLayout(lines: string[], fontSize: number): Layout { const glyphs: Glyph[] = []; const lineWidths: number[] = []; const adv = fontSize * 0.6; lines.forEach((line, li) => { const chars = Array.from(line); chars.forEach((char, ci) => { if (!/\s/.test(char)) glyphs.push({ char, line: li, x: ci * adv, w: adv }); }); lineWidths.push(chars.length * adv); }); return { glyphs, lineWidths, measured: false }; } /** Seeded strike: 2–3 uneven partial dips inside the first ~200ms of a glyph lighting. */ function strikeKeyframes(rng: () => number): Keyframe[] { const dips = rng() < 0.5 ? 2 : 3; const total = 240; const frames: Keyframe[] = [{ opacity: 0, offset: 0 }]; let t = 18 + rng() * 14; frames.push({ opacity: 0.85 + rng() * 0.15, offset: t / total }); for (let d = 0; d < dips; d++) { t += 22 + rng() * 22; frames.push({ opacity: 0.2 + rng() * 0.25, offset: Math.min(t, 200) / total }); t += 18 + rng() * 22; frames.push({ opacity: 0.8 + rng() * 0.2, offset: Math.min(t, 210) / total }); } frames.push({ opacity: 1, offset: 1 }); return frames; } /** Seeded ~400ms destabilise: exactly two partial dips, then a wobble back to steady. */ function flickerKeyframes(rng: () => number): Keyframe[] { return [ { opacity: 1, offset: 0 }, { opacity: 0.28 + rng() * 0.14, offset: 0.08 + rng() * 0.04 }, { opacity: 0.88 + rng() * 0.1, offset: 0.2 }, { opacity: 0.72 + rng() * 0.1, offset: 0.34 }, { opacity: 0.38 + rng() * 0.14, offset: 0.46 + rng() * 0.04 }, { opacity: 1, offset: 0.62 }, { opacity: 0.9 + rng() * 0.06, offset: 0.8 }, { opacity: 1, offset: 1 }, ]; } /** * Argon — a headline rendered as bent gas-discharge glass tubes. Each glyph * is an SVG text outline in three layers: a dim unlit tube, a bright lit core * with a white-hot center, and a blurred bloom. On view, ignition travels * along each tube glyph-by-glyph with an uneven strike flicker, then holds * with a near-imperceptible mains hum. The glyph nearest the pointer * destabilises briefly. Flicker is photosensitivity-budgeted (≤3 dips/s); * reduced motion renders the sign fully lit and steady. */ export function Argon({ text = "Open late", gas = "argon", as = "h2", fontSize = 96, strokeWidth = 2.4, clips = true, igniteOnView = true, intensity = 1, idle = true, paused = false, ref, className, style, ...props }: ArgonProps) { const reducedMotion = useReducedMotion(); const staticMode = reducedMotion || paused; const Tag = as; const uid = React.useId().replace(/:/g, ""); const filterId = `argon-bloom-${uid}`; const maskId = `argon-mask-${uid}`; const lines = React.useMemo(() => text.split("\n"), [text]); const seed = React.useMemo(() => hashString(text), [text]); const color = GAS_PRESETS[gas] ?? gas; const hot = `color-mix(in srgb, ${color} 42%, #ffffff)`; const k = Math.max(0, Math.min(2, intensity)); const [layout, setLayout] = React.useState(() => estimateLayout(lines, fontSize)); const [igniteKey, setIgniteKey] = React.useState(0); const [lit, setLit] = React.useState(false); const [inView, setInView] = React.useState(false); const [docVisible, setDocVisible] = React.useState(true); const svgRef = React.useRef(null); const measureRefs = React.useRef<(SVGTextElement | null)[]>([]); const dashRefs = React.useRef<(SVGTextElement | null)[][]>([]); const glowRefs = React.useRef<(SVGGElement | null)[]>([]); const bloomRefs = React.useRef<(SVGTextElement | null)[]>([]); const fillRefs = React.useRef<(SVGTextElement | null)[]>([]); const playedKeyRef = React.useRef(0); const activeFlickers = React.useRef(new Map()); const dipTimes = React.useRef([]); const flickerCount = React.useRef(0); const lastPointer = React.useRef(-Infinity); const hoverIndex = React.useRef(-1); // ---- geometry ----------------------------------------------------------- const pad = Math.max(strokeWidth * 6, fontSize * 0.2); const lineHeight = fontSize * 1.18; const ascent = fontSize * 0.8; const clipSpace = clips ? fontSize * 0.2 : 0; const maxLineWidth = Math.max(1, ...layout.lineWidths); const vbW = maxLineWidth + pad * 2; const vbH = pad * 2 + ascent + (lines.length - 1) * lineHeight + fontSize * 0.22 + clipSpace; const baselineOf = (line: number) => pad + ascent + line * lineHeight; const lineOffset = (line: number) => pad + (maxLineWidth - (layout.lineWidths[line] ?? 0)) / 2; const dashLen = fontSize * DASH_EM; // ---- measure real glyph advances (kerning + letter-spacing included) ----- const measure = React.useCallback(() => { const glyphs: Glyph[] = []; const lineWidths: number[] = []; lines.forEach((line, li) => { const el = measureRefs.current[li]; if (!el) { lineWidths.push(0); return; } let width = 0; try { width = el.getComputedTextLength(); } catch { width = 0; } lineWidths.push(width); let unit = 0; for (const char of Array.from(line)) { if (!/\s/.test(char)) { try { const start = el.getStartPositionOfChar(unit).x; const end = el.getEndPositionOfChar(unit + char.length - 1).x; glyphs.push({ char, line: li, x: start, w: Math.max(0, end - start) }); } catch { /* unaddressable character — skip */ } } unit += char.length; } }); setLayout({ glyphs, lineWidths, measured: true }); }, [lines]); React.useLayoutEffect(() => { measure(); const fonts = typeof document !== "undefined" ? document.fonts : undefined; if (!fonts) return; let alive = true; const onLoad = () => alive && measure(); fonts.ready.then(onLoad).catch(() => {}); fonts.addEventListener?.("loadingdone", onLoad); return () => { alive = false; fonts.removeEventListener?.("loadingdone", onLoad); }; }, [measure, fontSize]); // ---- visibility (in view + tab visible) --------------------------------- React.useEffect(() => { const node = svgRef.current; if (!node) return; if (typeof IntersectionObserver === "undefined") { setInView(true); return; } const io = new IntersectionObserver(([entry]) => setInView(!!entry?.isIntersecting), { threshold: 0.35, }); io.observe(node); return () => io.disconnect(); }, []); React.useEffect(() => { const onVis = () => setDocVisible(document.visibilityState !== "hidden"); onVis(); document.addEventListener("visibilitychange", onVis); return () => document.removeEventListener("visibilitychange", onVis); }, []); // ---- ignition trigger --------------------------------------------------- React.useEffect(() => { if (igniteKey !== 0) return; if (!igniteOnView || inView) setIgniteKey(1); }, [igniteOnView, inView, igniteKey]); // Static mode (reduced motion / paused): everything lit, nothing animating. React.useEffect(() => { if (!staticMode) return; playedKeyRef.current = Math.max(playedKeyRef.current, igniteKey); activeFlickers.current.forEach((a) => a.cancel()); activeFlickers.current.clear(); setLit(true); }, [staticMode, igniteKey]); const glyphCount = layout.glyphs.length; const measured = layout.measured; React.useLayoutEffect(() => { if (staticMode || !measured || igniteKey === 0 || playedKeyRef.current === igniteKey) return; playedKeyRef.current = igniteKey; setLit(false); activeFlickers.current.forEach((a) => a.cancel()); activeFlickers.current.clear(); const anims: Animation[] = []; const len = fontSize * DASH_EM; for (let i = 0; i < glyphCount; i++) { const delay = i * STAGGER; const rng = mulberry32(seed ^ Math.imul(i + 1, 0x9e3779b1) ^ Math.imul(igniteKey, 0x85ebca6b)); for (const el of dashRefs.current[i] ?? []) { if (!el?.animate) continue; anims.push( el.animate([{ strokeDashoffset: len }, { strokeDashoffset: 0 }], { duration: DRAW_MS, delay, easing: "cubic-bezier(0.3, 0.15, 0.55, 1)", fill: "both", }) ); } const strike = strikeKeyframes(rng); const g = glowRefs.current[i]; const b = bloomRefs.current[i]; if (g?.animate) anims.push(g.animate(strike, { duration: 240, delay, fill: "both" })); if (b?.animate) anims.push(b.animate(strike, { duration: 240, delay, fill: "both" })); const f = fillRefs.current[i]; if (f?.animate) { anims.push( f.animate([{ opacity: 0 }, { opacity: 1 }], { duration: 520, delay: delay + DRAW_MS * 0.3, easing: "ease-out", fill: "both", }) ); } } let cancelled = false; Promise.all(anims.map((a) => a.finished)) .then(() => { if (cancelled) return; setLit(true); // Committed state now matches the end frames — release the animations. anims.forEach((a) => a.cancel()); }) .catch(() => {}); return () => { cancelled = true; anims.forEach((a) => a.cancel()); }; }, [igniteKey, staticMode, measured, glyphCount, seed, fontSize]); // ---- flicker (hover / idle / handle) ------------------------------------ const flicker = React.useCallback( (index?: number) => { if (staticMode || !lit || glyphCount === 0) return; const n = flickerCount.current++; const rng = mulberry32(seed ^ Math.imul(n + 17, 0x27d4eb2f)); const i = index === undefined ? Math.floor(rng() * glyphCount) : Math.max(0, Math.min(glyphCount - 1, index)); if (activeFlickers.current.has(i)) return; const now = performance.now(); dipTimes.current = dipTimes.current.filter((t) => now - t < 1000); if (dipTimes.current.length + FLICKER_DIPS > MAX_DIPS_PER_SECOND) return; const frames = flickerKeyframes(rng); const opts: KeyframeAnimationOptions = { duration: 400, easing: "linear" }; const g = glowRefs.current[i]; const b = bloomRefs.current[i]; const f = fillRefs.current[i]; if (!g?.animate) return; dipTimes.current.push(now, now + 180); const a = g.animate(frames, opts); b?.animate?.(frames, opts); f?.animate?.(frames, opts); activeFlickers.current.set(i, a); const done = () => { if (activeFlickers.current.get(i) === a) activeFlickers.current.delete(i); }; a.finished.then(done, done); }, [staticMode, lit, glyphCount, seed] ); React.useImperativeHandle( ref, () => ({ replay: () => { if (staticMode) return; setIgniteKey((key) => key + 1); }, flicker, }), [flicker, staticMode] ); // Idle ghost: the sign occasionally destabilises on its own when nobody's pointing. const running = lit && !staticMode && inView && docVisible; React.useEffect(() => { if (!running || !idle) return; const rng = mulberry32(seed ^ 0x51ed27); let timer: ReturnType; const schedule = () => { timer = setTimeout( () => { if (performance.now() - lastPointer.current > 1500) flicker(); schedule(); }, 2600 + rng() * 3200 ); }; schedule(); return () => clearTimeout(timer); }, [running, idle, seed, flicker]); React.useEffect(() => { const flickers = activeFlickers.current; return () => { flickers.forEach((a) => a.cancel()); flickers.clear(); }; }, []); const nearestGlyph = (clientX: number, clientY: number) => { const svg = svgRef.current; const ctm = svg?.getScreenCTM(); if (!svg || !ctm) return -1; const p = new DOMPoint(clientX, clientY).matrixTransform(ctm.inverse()); let best = -1; let bestD = fontSize * 0.9; layout.glyphs.forEach((g, i) => { const cx = lineOffset(g.line) + g.x + g.w / 2; const cy = baselineOf(g.line) - fontSize * 0.36; const d = Math.hypot((p.x - cx) * 1.15, p.y - cy); if (d < bestD) { bestD = d; best = i; } }); return best; }; const onPointerMove = (e: React.PointerEvent) => { lastPointer.current = performance.now(); const i = nearestGlyph(e.clientX, e.clientY); if (i !== hoverIndex.current) { hoverIndex.current = i; if (i >= 0) flicker(i); } }; const onPointerDown = (e: React.PointerEvent) => { lastPointer.current = performance.now(); const i = nearestGlyph(e.clientX, e.clientY); if (i >= 0) flicker(i); }; const onPointerLeave = () => { lastPointer.current = performance.now(); hoverIndex.current = -1; }; // ---- render ------------------------------------------------------------- const restOffset = staticMode || lit ? 0 : dashLen; const restFill = staticMode || lit ? 1 : 0; const humming = lit && !staticMode; const bloomBlur = strokeWidth * (0.9 + 1.4 * k); const tubeTransition = "stroke 450ms ease, fill 450ms ease"; const textProps = (g: Glyph) => ({ x: lineOffset(g.line) + g.x, y: baselineOf(g.line), }); return ( {text} ); } ```