Synthwave sunset · nex-n2-pro

Create an animated synthwave sunset: a glowing gradient sun with scanlines setting over an infinite neon grid that scrolls toward the viewer, with a starfield and a reflected horizon.

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user

Create an animated synthwave sunset: a glowing gradient sun with scanlines setting over an infinite neon grid that scrolls toward the viewer, with a starfield and a reflected horizon.

assistant

thinking

We need answer by creating file index.html in current dir. Need inspect cwd maybe empty. Need build single-page animated synthwave sunset. Need use no external resources. Need write self-contained HTML CSS JS inline. Need end with index.html present. We need likely create file. We can use canvas for animation. Need include CSS style and JS script inline. Need maybe no external. Let's inspect maybe.

→ bash {"command":"ls -la /tmp/ws && pwd","timeout":5}

toolResult

total 0 drwxr-sr-x. 2 node node 6 Aug 1 20:53 . drwxrwsrwx. 3 root node 16 Aug 1 20:53 .. /tmp/ws

assistant

thinking

Need create index.html. Need maybe use canvas. Need implement animated synthwave sunset: glowing gradient sun with scanlines setting over infinite neon grid scrolls toward viewer, starfield, reflected horizon. Single-page web app. We can create full HTML with canvas animation. Need no external. Need maybe include fallback. Need "glowing gradient sun with scanlines" setting over "infinite neon grid" scrolls toward viewer. Starfield and reflected horizon. Need polished.

Need write file. Need maybe not too huge. Need ensure works. Let's plan code.

HTML:
<!doctype html>
<html lang=en>
<head>
<meta charset=utf-8>
<meta name=viewport content...
<title>Animated Synthwave Sunset</title>
<style> ... body background black, canvas full. overlay maybe title "NEON HORIZON" small. But user asked app, maybe canvas only. We can include controls? Could include no external. Need maybe interactive mouse parallax. But not necessary. Single-page web app.

Canvas animation:
- setup canvas high DPI.
- Use requestAnimationFrame.
- Draw background gradient sky from top #09001a to horizon #2c0038 maybe.
- Stars: array with x,y,z? Since no perspective for sky maybe twinkling. Generate 200 stars with x normalized, y top 0-55%, size, speed. Move slowly downward? Actually starfield. Could draw stars twinkle and drift.
- Sun: position at center, y around horizon minus maybe 100 plus animation? "setting" maybe slowly oscillates or descends. Could have sunY = horizon - 80 + sin(time*0.00015)*40? Setting over horizon maybe slowly moves down/up? Better "setting" = sun partially behind horizon, with scanlines clipped by horizon? Use draw sun above horizon with horizontal black/purple scanlines. Sun center y = horizon - 120 + 20*sin(t*0.0002). radius ~ min(width,height)*0.13. Draw radial gradient from yellow to orange to magenta. Draw clipped horizontal stripes: for y from center-r to center+r step 12, draw rect y height 4+sin. Need clip to circle. Use ctx.save(); clip circle; fill stripes with gradient/solid dark transparent. Maybe sun glow: radial gradient bigger.
- Reflected horizon: draw water band below horizon: gradient from magenta to black, with sun reflection vertical shimmering lines under sun. Also maybe horizontal wavy reflection of sun stripes. Need reflected horizon. Draw after grid? Maybe draw sky then sun then reflection then grid? In perspective, grid starts at horizon and extends to bottom. Reflected horizon could be below sun/horizon before grid? Synthwave grid usually on ground. "reflected horizon" maybe water reflection behind grid? We can draw a reflective water strip just below horizon, then grid over lower. But grid should be infinite neon grid scrolling toward viewer. We can draw grid from horizon to bottom. Reflection can be drawn over grid? Hmm.

Neon grid:
- Horizon y = h*0.55.
- Perspective grid: vertical lines converge to center vanishing point (w/2, horizon). Lines at x positions across horizon: x = vanishingX + spacingAtHorizon? Actually vertical grid lines: for i from -n to n, xHorizon = vanishingX + i*lineSpacingHorizon (maybe 50). xBottom = vanishingX + i*lineSpacingBottom (e.g., w/10). Draw line from horizon to bottom. Need infinite scrolling toward viewer: horizontal grid lines move downward with animation. Perspective y positions: y = horizon + (bottom - horizon) * (1 - 1/(1 + p?))? We can generate rows by depth. Use formula:
for i=0.. maybe 40:
  p = ((i + scroll) % 32)/32; // p 0 near horizon, 1 near bottom
  // Need nonlinear perspective: maybe y = horizon + (bottom - horizon) * (p*p) or y = horizon + (bottom-horizon)*(1 - Math.pow(1-p,3))? 
  // Infinite scroll: p = (i + offset) / n, where offset = (time*speed)%1; For each row i=0..n, p=(i+offset)/n. But rows near horizon should be dense, bottom sparse? We can use p = (i+offset)/n, y=horizon + (bottom-horizon)*Math.pow(p,2.2). This yields many rows near horizon. As offset increases, rows move down; when p >1 skip.
  // Alpha increases with p.
  // Line width maybe 1 + 2*p.
  // Draw horizontal line from left to right.
- Vertical lines: draw from vanishing point to bottom, with x at bottom spaced. Maybe also at horizon? x = vanishingX + i * spacingBottom? For i -20..20, xBottom = vanishingX + i * spacingBottom. At horizon all meet. Draw. Add glow.
- To enhance infinite, horizontal lines scroll downward. Could also add moving perspective "speed lines" on grid.
- Need draw grid after sun/reflection? Grid should cover reflection? In synthwave, grid foreground; horizon reflection behind grid. Draw sky, stars, sun, reflection, grid. Grid lines on top. Maybe reflection should be visible between grid.

- Add scanlines overlay: CSS? Could use canvas draw horizontal lines with alpha every 4 px. Also body after? Use CSS ::after? Since no external. Need scanlines on sun and screen. Could draw canvas scanlines with globalCompositeOperation screen maybe. But user specifically sun scanlines. We can draw sun stripes. Also screen scanline overlay.

- Add vignette, glow.

- Responsive.

- "animated synthwave sunset" maybe title and "click/tap for color shift"? Could include pointer parallax. Nice but not necessary. Maybe add interactive mouse/touch parallax for stars/sun/grid.

Need write index.html. Need maybe include comments. Need no external resources.

Potential code:

```
<!doctype html>
<html>
<head>
<meta ...>
<title>Animated Synthwave Sunset</title>
<style>
:root { color-scheme: dark; }
* { box-sizing: border-box; }
html, body { margin:0; width:100%; height:100%; overflow:hidden; background:#05000d; }
body { font-family: ...; }
canvas { display:block; width:100vw; height:100vh; background: radial-gradient(...); }
.hud { position: fixed; inset: 0; pointer-events:none; display:flex; align-items:flex-end; justify-content:center; padding-bottom:24px; color: rgba(...); text-shadow...}
.hud::before { ... scanline overlay? }
...
</style>
</head>
<body>
<canvas id="scene" aria-label=...></canvas>
<div class="hud">...</div>
<script>
(() => {
 const canvas = document.getElementById('scene');
 const ctx = canvas.getContext('2d');
 let w,h,dpr,horizon,vanishingX;
 let stars=[], gridRows=36;
 const pointer = {x:0,y:0};
 function resize() { dpr = Math.min(devicePixelRatio ||1, 2); w=innerWidth; h=innerHeight; canvas.width=Math.floor(w*dpr); canvas.height=Math.floor(h*dpr); canvas.style.width=w+'px'; canvas.style.height=h+'px'; ctx.setTransform(dpr,0,0,dpr,0,0); initStars(); horizon=Math.round(h*0.55); vanishingX=w*0.5; }
 function initStars(){ const count=Math.floor(Math.min(260, Math.max(100, w*h/6500))); stars = Array.from({length: count}, () => ({x: Math.random(), y: Math.random()*0.55, r: Math.random()*1.4+0.2, phase: Math.random()*Math.PI*2, drift: Math.random()*0.015+0.003}));}
 window.addEventListener('resize', resize, {passive:true});
 window.addEventListener('pointermove', e => { pointer.x = (e.clientX/w -0.5); pointer.y=(e.clientY/h -0.5); });
 window.addEventListener('pointerleave', ()=>{ pointer.x=0; pointer.y=0;});
 function drawBackground(t){ const pulse=...; const g=ctx.createLinearGradient(0,0,0,horizon); g.addColorStop(...); ctx.fillRect...; // nebula blobs radial gradients
 // stars
 for stars: x=(s.x*w + Math.sin(t*0.00002+s.phase)*80 + pointer.x*20*s.x) % w; y=s.y*horizon + Math.sin(t*0.0001+s.phase)*3 + pointer.y*10; alpha=...; ctx.fillStyle=`rgba(255,245,255,${alpha})`; ctx.fillRect? or arc.
}
function drawSun(t) {
 const r = Math.min(w,h)*0.13;
 const cx = w*0.5 + pointer.x*20;
 const cy = horizon - r*0.65 + Math.sin(t*0.00018)*18;
 // glow
 const glow=ctx.createRadialGradient(cx,cy,r*0.2,cx,cy,r*3.2); ...
 ctx.globalCompositeOperation='lighter'; fill circle; 
 // sun body gradient
 const sunGrad=ctx.createLinearGradient(0,cy-r,0,cy+r); ...
 ctx.beginPath(); ctx.arc(cx,cy,r,0,2pi); fill;
 // scanlines clipped
 ctx.save(); ctx.beginPath(); ctx.arc(cx,cy,r,0,2pi); ctx.clip(); for(let y=cy-r*0.35; y<cy+r; y+=r*0.13) { const stripeH = r*(0.045+0.025*Math.sin(t*0.002+y)); ctx.fillStyle=`rgba(20,0,38,${0.85})`; ctx.fillRect(cx-r, y + Math.sin(t*0.003+y)*1.5, r*2, stripeH); } ctx.restore();
 // maybe sun rim
}
function drawReflection(t) {
 const cx = w*0.5 + pointer.x*20;
 const cy = horizon - r*0.65 + Math.sin...
 const bottom = h;
 // water gradient
 const water=ctx.createLinearGradient(0,horizon,0,h); water.addColorStop(0,'rgba(255,30,170,.35)'); ... fillRect.
 // sun reflection columns/streaks
 ctx.globalCompositeOperation='lighter';
 for i=0..35:
   const x = cx + (i-17.5)*(r*0.18);
   const width = r*(0.08 + Math.random? but deterministic with sin)
   const y = horizon + ((i*37 + t*0.08) % (h-horizon)) ??? Need shimmer.
   Draw vertical wavy strokes under sun:
   ctx.strokeStyle = rgba(255, 80, 180, alpha)
   ctx.beginPath(); for y horizon..bottom step 10: x + Math.sin(y*0.04 + t*0.002 + i)* (8+...); lineWidth; 
 // horizontal reflection bands
 for y=horizon+20; y<h; y += 14 + (y-horizon)*0.02: alpha = ...; draw line from cx - width to cx+width with gradient? 
}
```
But using Math.random in draw not good. Use deterministic sin.

Grid:
```
function drawGrid(t) {
 const bottom = h + 40;
 const nearW = Math.max(w*1.2, 1200);
 const farW = Math.max(w*0.35, 240);
 const vanishingY = horizon;
 const scroll = (t * 0.00022) % 1;
 ctx.save(); ctx.globalCompositeOperation='lighter';
 // horizontal rows
 ctx.lineWidth = 1;
 for (let i=0; i<42; i++) {
   const p = (i + scroll) / 42;
   if (p <= 0 || p >= 1) continue;
   const y = horizon + Math.pow(p, 2.65) * (bottom - horizon);
   const alpha = 0.05 + p*0.75;
   const hue = 290 + 50*p;
   ctx.strokeStyle = `hsla(${hue}, 100%, 65%, ${alpha})`;
   ctx.shadowBlur = 12 + p*16;
   ctx.shadowColor = `hsl(${hue}, 100%, 60%)`;
   ctx.lineWidth = 0.8 + p*1.8;
   ctx.beginPath();
   ctx.moveTo(0,y);
   ctx.lineTo(w,y);
   ctx.stroke();
 }
 // vertical lines
 const lines = 23;
 for (let i=-lines; i<=lines; i++) {
   const x0 = vanishingX + i * 28; // at horizon? But at horizon all same if x0 = vanishingX + i*28 and x1 = vanishingX + i * nearW/lines; line not converging to vanishingX exactly? Use xHorizon = vanishingX + i*farW/lines maybe; xBottom = vanishingX + i*nearW/lines.
   const xH = vanishingX + i * (farW / lines);
   const xB = vanishingX + i * (nearW / lines);
   // maybe draw from xH,horizon to xB,bottom. If xH != vanishingX, horizon lines don't converge exactly but enough. Better xH = vanishingX + i*3? But then vertical lines at horizon separated; no, perspective lines converge at vanishing point. Use xH = vanishingX.
   const xB = vanishingX + i * (nearW / lines);
   ctx.strokeStyle = ...
   ctx.beginPath(); moveTo(vanishingX, horizon); lineTo(xB,bottom); stroke;
 }
 // maybe side grid perspective arcs? 
 ctx.restore();
 // dark grid underlay? 
}
```
Maybe draw a "floor" dark fill below horizon before grid:
```
const ground = ctx.createLinearGradient(0,horizon,0,h);
ground.addColorStop(0,'rgba(10,0,35,.15)');
ground.addColorStop(1,'rgba(0,0,0,.9)');
ctx.fillRect(0,horizon,w,h-horizon);
```
But reflection should be behind. Need draw reflection before grid maybe with fill gradient.

Scanlines overlay:
```
function drawScreenScanlines(t) {
 ctx.save();
 ctx.globalAlpha = 0.12;
 ctx.fillStyle = '#000';
 for (let y = (t*0.02)%4; y<h; y+=4) ctx.fillRect(0,y,w,1);
 ctx.restore();
}
```
CSS overlay can do scanlines; but no external.

Maybe use `prefers-reduced-motion`? Could stop if reduced. But animation requested. We can respect? Maybe not. Could have CSS.

Need maybe include "app" maybe a small header? But maybe title overlay might distract. Use minimal HUD:
```
<div class="hud">
  <div class="badge">NEON HORIZON</div>
</div>
```
Maybe no controls. User didn't ask. But "single-page web app" can be canvas. Maybe include pointer parallax.

Need ensure no network. Fonts: use system fonts only. No external.

Need file write.

→ write /tmp/ws/index.html (15790 bytes)

toolResult

Successfully wrote 15790 bytes to /tmp/ws/index.html

assistant

thinking

Need verify file present maybe maybe run simple grep?

→ bash {"command":"ls -l /tmp/ws/index.html && head -n 5 /tmp/ws/index.html","timeout":5}

toolResult

-rw-r--r--. 1 node node 15790 Aug 1 20:54 /tmp/ws/index.html <!doctype html> <html lang="en"> <head> <meta charset="utf-8" /> <meta name="viewport" content="width=device-width, initial-scale=1" />

assistant

thinking

Done — `index.html` is present in the current directory with the full self-contained animated synthwave sunset.

TAKE IT TO CODE

A single self-contained HTML file — copy it and open in any browser, or reuse the prompt with your own pi-agent run.

RUN

modelnex-n2-pro

vendorNex AGI

harnesspi-agent

generated2026-08-01

EVALUATION

★★★★★ 4/5 working

Animated synthwave sun with scanlines, starfield, glowing horizon and grid; grid pulses/scrolls but no keyboard/mouse interactivity.

Vision grade · anthropic/claude-sonnet-5

MEASUREMENTS

Raw readings from the capture, not a verdict — the grade above is the only judgement. Percentages are how much of the screen changed; the measure under-reports sparse motion on a dark background.

idle motion23.8%

frame spread41.7 / 255

console errors0

js errors none

METRICS

runtime64.2s

tokens in10k

tokens out9.7k

cached16k

cost / run$0.0126