初始化项目并上传代码

app.js

@@ -0,0 +1,549 @@
+(function (global) {
+  'use strict';
+
+  const PATTERNS = {
+    glider: {
+      name: 'Glider',
+      cells: [
+        [0, 1],
+        [1, 2],
+        [2, 0],
+        [2, 1],
+        [2, 2],
+      ],
+    },
+    pulsar: {
+      name: 'Pulsar',
+      cells: [
+        [0, 2], [0, 3], [0, 4], [0, 8], [0, 9], [0, 10],
+        [2, 0], [2, 5], [2, 7], [2, 12],
+        [3, 0], [3, 5], [3, 7], [3, 12],
+        [4, 0], [4, 5], [4, 7], [4, 12],
+        [5, 2], [5, 3], [5, 4], [5, 8], [5, 9], [5, 10],
+        [7, 2], [7, 3], [7, 4], [7, 8], [7, 9], [7, 10],
+        [8, 0], [8, 5], [8, 7], [8, 12],
+        [9, 0], [9, 5], [9, 7], [9, 12],
+        [10, 0], [10, 5], [10, 7], [10, 12],
+        [12, 2], [12, 3], [12, 4], [12, 8], [12, 9], [12, 10],
+      ],
+    },
+    gosperGliderGun: {
+      name: 'Gosper Glider Gun',
+      cells: [
+        [0, 24],
+        [1, 22], [1, 24],
+        [2, 12], [2, 13], [2, 20], [2, 21], [2, 34], [2, 35],
+        [3, 11], [3, 15], [3, 20], [3, 21], [3, 34], [3, 35],
+        [4, 0], [4, 1], [4, 10], [4, 16], [4, 20], [4, 21],
+        [5, 0], [5, 1], [5, 10], [5, 14], [5, 16], [5, 17], [5, 22], [5, 24],
+        [6, 10], [6, 16], [6, 24],
+        [7, 11], [7, 15],
+        [8, 12], [8, 13],
+      ],
+    },
+  };
+
+  function createEmptyGrid(rows, cols) {
+    return Array.from({ length: rows }, function () {
+      return Array(cols).fill(0);
+    });
+  }
+
+  function cloneGrid(grid) {
+    return grid.map(function (row) {
+      return row.slice();
+    });
+  }
+
+  function countLiveNeighbors(grid, row, col) {
+    let total = 0;
+
+    for (let rowOffset = -1; rowOffset <= 1; rowOffset += 1) {
+      for (let colOffset = -1; colOffset <= 1; colOffset += 1) {
+        if (rowOffset === 0 && colOffset === 0) {
+          continue;
+        }
+
+        const nextRow = row + rowOffset;
+        const nextCol = col + colOffset;
+
+        if (
+          nextRow >= 0 &&
+          nextRow < grid.length &&
+          nextCol >= 0 &&
+          nextCol < grid[0].length
+        ) {
+          total += grid[nextRow][nextCol];
+        }
+      }
+    }
+
+    return total;
+  }
+
+  function stepGrid(grid) {
+    return grid.map(function (cells, rowIndex) {
+      return cells.map(function (cell, colIndex) {
+        const neighbors = countLiveNeighbors(grid, rowIndex, colIndex);
+
+        if (cell === 1) {
+          return neighbors === 2 || neighbors === 3 ? 1 : 0;
+        }
+
+        return neighbors === 3 ? 1 : 0;
+      });
+    });
+  }
+
+  function stampPattern(grid, pattern, offsetRow, offsetCol) {
+    pattern.cells.forEach(function (cell) {
+      const row = cell[0] + offsetRow;
+      const col = cell[1] + offsetCol;
+
+      if (row >= 0 && row < grid.length && col >= 0 && col < grid[0].length) {
+        grid[row][col] = 1;
+      }
+    });
+
+    return grid;
+  }
+
+  function countLiveCells(grid) {
+    return grid.reduce(function (total, row) {
+      return total + row.reduce(function (rowTotal, cell) {
+        return rowTotal + cell;
+      }, 0);
+    }, 0);
+  }
+
+  function centerPattern(grid, pattern) {
+    const lastRow = pattern.cells.reduce(function (maxRow, cell) {
+      return Math.max(maxRow, cell[0]);
+    }, 0);
+    const lastCol = pattern.cells.reduce(function (maxCol, cell) {
+      return Math.max(maxCol, cell[1]);
+    }, 0);
+    const offsetRow = Math.max(0, Math.floor((grid.length - (lastRow + 1)) / 2));
+    const offsetCol = Math.max(0, Math.floor((grid[0].length - (lastCol + 1)) / 2));
+
+    return stampPattern(grid, pattern, offsetRow, offsetCol);
+  }
+
+  function createInitialState(options) {
+    const rows = options.rows;
+    const cols = options.cols;
+    const defaultPattern = options.defaultPattern || 'pulsar';
+    const grid = createEmptyGrid(rows, cols);
+
+    centerPattern(grid, PATTERNS[defaultPattern]);
+
+    return {
+      cols: cols,
+      defaultPattern: defaultPattern,
+      generation: 0,
+      grid: grid,
+      liveCount: countLiveCells(grid),
+      rows: rows,
+      running: false,
+      selectedPattern: defaultPattern,
+      speed: 1,
+    };
+  }
+
+  function randomizeGrid(grid, probability) {
+    const chance = typeof probability === 'number' ? probability : 0.28;
+
+    return grid.map(function (row) {
+      return row.map(function () {
+        return Math.random() < chance ? 1 : 0;
+      });
+    });
+  }
+
+  function toggleCell(grid, row, col, forcedValue) {
+    const next = cloneGrid(grid);
+
+    if (row < 0 || row >= next.length || col < 0 || col >= next[0].length) {
+      return next;
+    }
+
+    next[row][col] = typeof forcedValue === 'number' ? forcedValue : next[row][col] ? 0 : 1;
+    return next;
+  }
+
+  function applyPreset(state, patternName) {
+    const grid = createEmptyGrid(state.rows, state.cols);
+    const nextPattern = PATTERNS[patternName] ? patternName : state.defaultPattern;
+
+    centerPattern(grid, PATTERNS[nextPattern]);
+
+    return {
+      cols: state.cols,
+      defaultPattern: state.defaultPattern,
+      generation: 0,
+      grid: grid,
+      liveCount: countLiveCells(grid),
+      rows: state.rows,
+      running: false,
+      selectedPattern: nextPattern,
+      speed: state.speed,
+    };
+  }
+
+  function advanceState(state) {
+    const nextGrid = stepGrid(state.grid);
+
+    return Object.assign({}, state, {
+      generation: state.generation + 1,
+      grid: nextGrid,
+      liveCount: countLiveCells(nextGrid),
+    });
+  }
+
+  function setSpeed(state, speed) {
+    return Object.assign({}, state, {
+      speed: Math.max(1, Math.min(6, speed)),
+    });
+  }
+
+  function getSpeedLabel(speed) {
+    if (speed <= 1) {
+      return 'Drift';
+    }
+
+    if (speed <= 3) {
+      return 'Pulse';
+    }
+
+    if (speed <= 5) {
+      return 'Hyper';
+    }
+
+    return 'Lightstorm';
+  }
+
+  function getSpeedDelay(speed) {
+    const delays = {
+      1: 520,
+      2: 340,
+      3: 220,
+      4: 140,
+      5: 90,
+      6: 60,
+    };
+
+    return delays[Math.max(1, Math.min(6, speed))];
+  }
+
+  function getPatternLabel(patternName) {
+    return PATTERNS[patternName] ? PATTERNS[patternName].name : 'Custom';
+  }
+
+  function createEmptyLike(state) {
+    return createEmptyGrid(state.rows, state.cols);
+  }
+
+  function replaceGrid(state, grid, selectedPattern) {
+    return Object.assign({}, state, {
+      generation: 0,
+      grid: grid,
+      liveCount: countLiveCells(grid),
+      running: false,
+      selectedPattern: selectedPattern || 'custom',
+    });
+  }
+
+  function getCanvasPoint(event, canvas, state) {
+    const rect = canvas.getBoundingClientRect();
+    const col = Math.floor(((event.clientX - rect.left) / rect.width) * state.cols);
+    const row = Math.floor(((event.clientY - rect.top) / rect.height) * state.rows);
+
+    if (row < 0 || row >= state.rows || col < 0 || col >= state.cols) {
+      return null;
+    }
+
+    return { row: row, col: col };
+  }
+
+  function resizeCanvas(canvas) {
+    const ratio = global.devicePixelRatio || 1;
+    const bounds = canvas.getBoundingClientRect();
+    const width = Math.max(1, Math.floor(bounds.width * ratio));
+    const height = Math.max(1, Math.floor(bounds.height * ratio));
+
+    if (canvas.width !== width || canvas.height !== height) {
+      canvas.width = width;
+      canvas.height = height;
+    }
+  }
+
+  function drawSimulation(canvas, state) {
+    const context = canvas.getContext('2d');
+    const width = canvas.width;
+    const height = canvas.height;
+    const cellWidth = width / state.cols;
+    const cellHeight = height / state.rows;
+    const inset = Math.max(1.5, Math.min(cellWidth, cellHeight) * 0.12);
+
+    context.clearRect(0, 0, width, height);
+
+    const background = context.createLinearGradient(0, 0, width, height);
+    background.addColorStop(0, '#081321');
+    background.addColorStop(1, '#040a13');
+    context.fillStyle = background;
+    context.fillRect(0, 0, width, height);
+
+    const bloom = context.createRadialGradient(width * 0.18, height * 0.16, 0, width * 0.18, height * 0.16, width * 0.55);
+    bloom.addColorStop(0, 'rgba(115, 240, 221, 0.15)');
+    bloom.addColorStop(1, 'rgba(115, 240, 221, 0)');
+    context.fillStyle = bloom;
+    context.fillRect(0, 0, width, height);
+
+    context.beginPath();
+    context.strokeStyle = 'rgba(126, 192, 212, 0.1)';
+    context.lineWidth = 1;
+
+    for (let row = 0; row <= state.rows; row += 1) {
+      const y = Math.round(row * cellHeight) + 0.5;
+      context.moveTo(0, y);
+      context.lineTo(width, y);
+    }
+
+    for (let col = 0; col <= state.cols; col += 1) {
+      const x = Math.round(col * cellWidth) + 0.5;
+      context.moveTo(x, 0);
+      context.lineTo(x, height);
+    }
+
+    context.stroke();
+
+    for (let rowIndex = 0; rowIndex < state.rows; rowIndex += 1) {
+      for (let colIndex = 0; colIndex < state.cols; colIndex += 1) {
+        if (!state.grid[rowIndex][colIndex]) {
+          continue;
+        }
+
+        const x = colIndex * cellWidth + inset;
+        const y = rowIndex * cellHeight + inset;
+        const drawWidth = Math.max(2, cellWidth - inset * 2);
+        const drawHeight = Math.max(2, cellHeight - inset * 2);
+        const fill = context.createLinearGradient(x, y, x + drawWidth, y + drawHeight);
+
+        fill.addColorStop(0, 'rgba(115, 240, 221, 0.98)');
+        fill.addColorStop(1, 'rgba(190, 252, 125, 0.94)');
+        context.fillStyle = fill;
+        context.shadowColor = 'rgba(115, 240, 221, 0.4)';
+        context.shadowBlur = Math.max(8, Math.min(cellWidth, cellHeight) * 0.66);
+        context.fillRect(x, y, drawWidth, drawHeight);
+      }
+    }
+
+    context.shadowBlur = 0;
+  }
+
+  function renderState(state, refs) {
+    resizeCanvas(refs.canvas);
+    drawSimulation(refs.canvas, state);
+
+    refs.statusText.textContent = state.running ? 'Running' : 'Paused';
+    refs.statusText.classList.toggle('running', state.running);
+    refs.speedLabel.textContent = getSpeedLabel(state.speed);
+    refs.speedReadout.textContent = state.speed + ' / 6';
+    refs.generationValue.textContent = String(state.generation);
+    refs.liveValue.textContent = String(state.liveCount);
+    refs.presetValue.textContent = getPatternLabel(state.selectedPattern);
+    refs.heroGeneration.textContent = String(state.generation);
+    refs.heroLive.textContent = String(state.liveCount);
+    refs.heroPattern.textContent = getPatternLabel(state.selectedPattern);
+    refs.canvasHint.textContent = state.running ? '演化进行中，拖拽会自动暂停' : '点击或拖拽即可绘制细胞';
+    refs.playToggle.textContent = state.running ? '暂停演化' : '开始演化';
+    refs.stepButton.disabled = state.running;
+    refs.speedSlider.value = String(state.speed);
+
+    refs.presetButtons.forEach(function (button) {
+      button.classList.toggle('active', button.dataset.pattern === state.selectedPattern);
+    });
+  }
+
+  function initDemo() {
+    const canvas = document.getElementById('life-canvas');
+
+    if (!canvas) {
+      return;
+    }
+
+    const refs = {
+      canvas: canvas,
+      canvasHint: document.getElementById('canvas-hint'),
+      clearButton: document.getElementById('clear-button'),
+      generationValue: document.getElementById('generation-value'),
+      heroGeneration: document.getElementById('hero-generation'),
+      heroLive: document.getElementById('hero-live'),
+      heroPattern: document.getElementById('hero-pattern'),
+      liveValue: document.getElementById('live-value'),
+      loadDefaultHero: document.getElementById('load-default-hero'),
+      playToggle: document.getElementById('play-toggle'),
+      presetButtons: Array.from(document.querySelectorAll('[data-pattern]')),
+      presetValue: document.getElementById('preset-value'),
+      randomButton: document.getElementById('random-button'),
+      resetButton: document.getElementById('reset-button'),
+      speedLabel: document.getElementById('speed-label'),
+      speedReadout: document.getElementById('speed-readout'),
+      speedSlider: document.getElementById('speed-slider'),
+      statusText: document.getElementById('status-text'),
+      stepButton: document.getElementById('step-button'),
+    };
+    const baseSize = global.innerWidth <= 720 ? 34 : 44;
+    let state = createInitialState({
+      rows: baseSize,
+      cols: baseSize,
+      defaultPattern: 'pulsar',
+    });
+    let lastTick = 0;
+    let drawing = false;
+    let drawValue = 1;
+    let lastCellKey = '';
+
+    function setState(nextState) {
+      state = nextState;
+      renderState(state, refs);
+    }
+
+    function applyCanvasPoint(event) {
+      const point = getCanvasPoint(event, refs.canvas, state);
+
+      if (!point) {
+        return;
+      }
+
+      const cellKey = point.row + ':' + point.col;
+
+      if (cellKey === lastCellKey) {
+        return;
+      }
+
+      lastCellKey = cellKey;
+      const nextGrid = toggleCell(state.grid, point.row, point.col, drawValue);
+      setState(replaceGrid(state, nextGrid, 'custom'));
+    }
+
+    refs.playToggle.addEventListener('click', function () {
+      setState(Object.assign({}, state, {
+        running: !state.running,
+      }));
+    });
+
+    refs.stepButton.addEventListener('click', function () {
+      if (!state.running) {
+        setState(advanceState(state));
+      }
+    });
+
+    refs.clearButton.addEventListener('click', function () {
+      setState(replaceGrid(state, createEmptyLike(state), 'custom'));
+    });
+
+    refs.randomButton.addEventListener('click', function () {
+      setState(replaceGrid(state, randomizeGrid(createEmptyLike(state), 0.22), 'custom'));
+    });
+
+    refs.resetButton.addEventListener('click', function () {
+      const patternName = PATTERNS[state.selectedPattern] ? state.selectedPattern : state.defaultPattern;
+      setState(applyPreset(state, patternName));
+    });
+
+    refs.loadDefaultHero.addEventListener('click', function () {
+      setState(applyPreset(state, state.defaultPattern));
+      document.getElementById('lab').scrollIntoView({ behavior: 'smooth', block: 'start' });
+    });
+
+    refs.speedSlider.addEventListener('input', function (event) {
+      const speed = Number(event.target.value);
+      setState(setSpeed(state, speed));
+    });
+
+    refs.presetButtons.forEach(function (button) {
+      button.addEventListener('click', function () {
+        setState(applyPreset(state, button.dataset.pattern));
+      });
+    });
+
+    refs.canvas.addEventListener('pointerdown', function (event) {
+      const point = getCanvasPoint(event, refs.canvas, state);
+
+      if (!point) {
+        return;
+      }
+
+      drawing = true;
+      lastCellKey = '';
+      drawValue = state.grid[point.row][point.col] ? 0 : 1;
+      refs.canvas.setPointerCapture(event.pointerId);
+      applyCanvasPoint(event);
+    });
+
+    refs.canvas.addEventListener('pointermove', function (event) {
+      if (!drawing) {
+        return;
+      }
+
+      applyCanvasPoint(event);
+    });
+
+    function stopDrawing(event) {
+      if (drawing && event && refs.canvas.hasPointerCapture(event.pointerId)) {
+        refs.canvas.releasePointerCapture(event.pointerId);
+      }
+
+      drawing = false;
+      lastCellKey = '';
+    }
+
+    refs.canvas.addEventListener('pointerup', stopDrawing);
+    refs.canvas.addEventListener('pointerleave', stopDrawing);
+
+    global.addEventListener('resize', function () {
+      renderState(state, refs);
+    });
+
+    function animate(timestamp) {
+      if (state.running && timestamp - lastTick >= getSpeedDelay(state.speed)) {
+        lastTick = timestamp;
+        setState(advanceState(state));
+      }
+
+      global.requestAnimationFrame(animate);
+    }
+
+    renderState(state, refs);
+    global.requestAnimationFrame(animate);
+  }
+
+  const api = {
+    advanceState: advanceState,
+    applyPreset: applyPreset,
+    PATTERNS: PATTERNS,
+    cloneGrid: cloneGrid,
+    countLiveNeighbors: countLiveNeighbors,
+    countLiveCells: countLiveCells,
+    createInitialState: createInitialState,
+    createEmptyGrid: createEmptyGrid,
+    getSpeedDelay: getSpeedDelay,
+    getSpeedLabel: getSpeedLabel,
+    randomizeGrid: randomizeGrid,
+    setSpeed: setSpeed,
+    stampPattern: stampPattern,
+    stepGrid: stepGrid,
+    toggleCell: toggleCell,
+  };
+
+  if (typeof module !== 'undefined' && module.exports) {
+    module.exports = api;
+  }
+
+  global.LifeDemo = api;
+
+  if (typeof document !== 'undefined') {
+    document.addEventListener('DOMContentLoaded', initDemo);
+  }
+})(typeof window !== 'undefined' ? window : globalThis);

docs/superpowers/plans/2026-03-17-conway-life-demo.md

@@ -0,0 +1,226 @@
+# Conway Life Demo Implementation Plan
+
+> **For agentic workers:** REQUIRED: Use superpowers:subagent-driven-development (if subagents available) or superpowers:executing-plans to implement this plan. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Build a direct-open Conway's Game of Life demo page with a modern visualization style, preset patterns, canvas-based simulation, and a clean teaching-plus-exploration flow.
+
+**Architecture:** Keep the page build-free and local-file friendly: semantic markup in `index.html`, visual styling in `styles.css`, and a single browser script in `app.js`. Put Conway engine logic and state helpers in testable pure functions exported from `app.js`, while the DOM/controller layer wires those functions to the canvas UI.
+
+**Tech Stack:** HTML5, CSS3, vanilla JavaScript, Canvas API, Node.js built-in test runner (`node --test`)
+
+---
+
+Note: this workspace is not a git repository, so commit steps are intentionally omitted.
+
+## File Structure
+
+- Create: `index.html` - page structure, content sections, script/style includes
+- Create: `styles.css` - theme variables, layout, cards, control panel, responsive styling, animation polish
+- Create: `app.js` - Conway engine, preset definitions, state helpers, canvas rendering, UI events
+- Create: `tests/life-demo.test.js` - Node tests for pure simulation and state logic
+
+## Chunk 1: Build and test the Conway engine
+
+### Task 1: Create the failing engine tests
+
+**Files:**
+- Create: `tests/life-demo.test.js`
+- Test: `tests/life-demo.test.js`
+
+- [ ] **Step 1: Write the failing test**
+
+```js
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const {
+  createEmptyGrid,
+  stepGrid,
+  stampPattern,
+  PATTERNS,
+} = require('../app.js');
+
+test('blinker rotates after one generation', () => {
+  const grid = createEmptyGrid(5, 5);
+  grid[2][1] = 1;
+  grid[2][2] = 1;
+  grid[2][3] = 1;
+
+  const next = stepGrid(grid);
+
+  assert.deepEqual(next[1], [0, 0, 1, 0, 0]);
+});
+```
+
+- [ ] **Step 2: Run test to verify it fails**
+
+Run: `node --test tests/life-demo.test.js`
+Expected: FAIL because `app.js` or the exported functions do not exist yet.
+
+- [ ] **Step 3: Write minimal implementation**
+
+```js
+function createEmptyGrid(rows, cols) {
+  return Array.from({ length: rows }, () => Array(cols).fill(0));
+}
+```
+
+Implement the smallest export set needed to pass:
+- `createEmptyGrid(rows, cols)`
+- `countLiveNeighbors(grid, row, col)`
+- `stepGrid(grid)`
+- `stampPattern(grid, pattern, offsetRow, offsetCol)`
+- `PATTERNS` for `glider`, `pulsar`, and `gosperGliderGun`
+
+- [ ] **Step 4: Run test to verify it passes**
+
+Run: `node --test tests/life-demo.test.js`
+Expected: PASS for the engine tests.
+
+## Chunk 2: Add state helpers and page shell
+
+### Task 2: Add failing tests for state helpers
+
+**Files:**
+- Modify: `tests/life-demo.test.js`
+- Modify: `app.js`
+- Create: `index.html`
+- Create: `styles.css`
+
+- [ ] **Step 1: Write the failing test**
+
+Add tests for:
+
+```js
+test('createInitialState seeds the default preset and starts paused', () => {
+  const state = createInitialState({
+    rows: 20,
+    cols: 20,
+    defaultPattern: 'pulsar',
+  });
+
+  assert.equal(state.running, false);
+  assert.equal(state.selectedPattern, 'pulsar');
+  assert.equal(state.generation, 0);
+  assert.ok(state.liveCount > 0);
+});
+```
+
+- [ ] **Step 2: Run test to verify it fails**
+
+Run: `node --test tests/life-demo.test.js`
+Expected: FAIL because `createInitialState` is not implemented yet.
+
+- [ ] **Step 3: Write minimal implementation**
+
+Implement pure helpers:
+- `cloneGrid(grid)`
+- `countLiveCells(grid)`
+- `createInitialState({ rows, cols, defaultPattern })`
+- `randomizeGrid(grid, probability)`
+- `toggleCell(grid, row, col, forcedValue)`
+
+At the same time, scaffold:
+- `index.html` with Hero, Lab, Rules, and Presets sections
+- `styles.css` with the modern visualization theme variables and responsive grid
+
+- [ ] **Step 4: Run test to verify it passes**
+
+Run: `node --test tests/life-demo.test.js`
+Expected: PASS for the new state-helper tests.
+
+## Chunk 3: Wire controls, canvas rendering, and preset switching
+
+### Task 3: Add failing tests for UI-facing state transitions
+
+**Files:**
+- Modify: `tests/life-demo.test.js`
+- Modify: `app.js`
+- Modify: `index.html`
+- Modify: `styles.css`
+
+- [ ] **Step 1: Write the failing test**
+
+Add tests for:
+
+```js
+test('applyPreset replaces the grid, pauses playback, and resets generation', () => {
+  const state = {
+    ...createInitialState({ rows: 25, cols: 25, defaultPattern: 'glider' }),
+    running: true,
+    generation: 12,
+  };
+
+  const next = applyPreset(state, 'gosperGliderGun');
+
+  assert.equal(next.running, false);
+  assert.equal(next.generation, 0);
+  assert.equal(next.selectedPattern, 'gosperGliderGun');
+  assert.ok(next.liveCount > state.liveCount);
+});
+```
+
+- [ ] **Step 2: Run test to verify it fails**
+
+Run: `node --test tests/life-demo.test.js`
+Expected: FAIL because `applyPreset` is not implemented yet.
+
+- [ ] **Step 3: Write minimal implementation**
+
+Implement:
+- `applyPreset(state, patternName)`
+- `advanceState(state)`
+- `setSpeed(state, speed)`
+- `getSpeedLabel(speed)`
+
+Then wire browser behavior:
+- draw the grid on a `canvas`
+- support play/pause, step, clear, randomize, reset preset, and speed controls
+- support click and drag painting on the canvas
+- update status text, generation count, live-count, and active preset styling
+
+- [ ] **Step 4: Run test to verify it passes**
+
+Run: `node --test tests/life-demo.test.js`
+Expected: PASS for the state-transition tests.
+
+## Chunk 4: Polish visual details and run end-to-end verification
+
+### Task 4: Finish presentation details and verify manually
+
+**Files:**
+- Modify: `index.html`
+- Modify: `styles.css`
+- Modify: `app.js`
+- Test: `tests/life-demo.test.js`
+
+- [ ] **Step 1: Refine the visuals**
+
+Complete:
+- luminous background gradients and grid accents
+- polished cards and control panel surfaces
+- hover/focus states
+- responsive stacking for smaller screens
+- subtle canvas/section entrance motion
+
+- [ ] **Step 2: Run automated tests**
+
+Run: `node --test tests/life-demo.test.js`
+Expected: PASS with zero failures.
+
+- [ ] **Step 3: Run manual verification**
+
+Open: `index.html`
+
+Verify:
+- page opens directly without a dev server
+- pulsar loads by default and the simulation starts paused
+- controls behave correctly
+- each preset loads and pauses correctly
+- editing by click/drag works
+- desktop and narrow layouts both remain usable
+
+- [ ] **Step 4: Record any gaps**
+
+If a browser-only issue appears, fix it and rerun:
+- `node --test tests/life-demo.test.js`
+- manual browser verification of `index.html`

docs/superpowers/specs/2026-03-17-conway-life-demo-design.md

@@ -0,0 +1,105 @@
+# Conway Life Demo Design
+
+Date: 2026-03-17
+Status: Approved
+
+## Goal
+
+Build a pure HTML/CSS/JS demo page for Conway's Game of Life that opens directly from `index.html`, balances teaching and interaction, and presents the simulation with a modern visualization aesthetic.
+
+## Audience and Use Case
+
+- Learners seeing cellular automata for the first time
+- Users who want to experiment by drawing patterns and watching them evolve
+- Anyone who wants a polished, shareable standalone demo page
+
+## Product Direction
+
+- Topic: Conway's Game of Life
+- Page type: balanced demo page
+- Delivery: direct-open HTML/CSS/JS page
+- Feature scope: enhanced version with preset patterns
+- Visual style: modern visualization
+- Default state: load a preset pattern and remain paused
+
+## Layout
+
+### 1. Hero
+
+- Full-width first screen with an atmospheric simulation-inspired background
+- Title, short explanatory subtitle, and a clear entry action that scrolls to the lab
+- Visual treatment based on luminous grid lines, soft glow, and scientific/data-art styling
+
+### 2. Main Lab
+
+- Large simulation canvas as the primary focus
+- Side control panel on desktop; stacked layout on mobile
+- Status area showing running/paused state and current speed
+
+### 3. Rules Section
+
+- Three compact rule cards explaining survival, birth, and death
+- Short copy only; no heavy educational text blocks
+- Small visual motifs to keep the explanation approachable
+
+### 4. Preset Pattern Section
+
+- Presets: glider, pulsar, and Gosper glider gun
+- Clicking a preset loads it into the simulation and pauses playback
+- Section doubles as both a teaching aid and a quick demo launcher
+
+## Interaction Design
+
+### Controls
+
+- Start/Pause
+- Step one generation
+- Clear
+- Randomize
+- Reset to selected preset
+- Speed adjustment
+
+### Canvas Interaction
+
+- Click a cell to toggle it
+- Drag to paint cells continuously
+- Keep the simulation paused when loading or editing presets so the user stays in control
+
+### Simulation Rules
+
+- Classic Conway rules
+- Finite grid with non-wrapping edges
+- Default opening preset: pulsar
+
+## Visual System
+
+- Deep dark background with cool white text
+- Cyan and acid-green highlights for live-state emphasis
+- Semi-transparent panels, subtle borders, soft bloom, and layered gradients
+- Refined motion: gentle glow, state transitions, and staggered reveal rather than flashy arcade effects
+
+## Technical Approach
+
+- Use `canvas` for the simulation surface to keep updates smooth and visually polished
+- Keep simulation rules in pure functions so they can be tested outside the browser
+- Keep page assets local so `index.html` can open directly without a build step
+
+## Responsiveness
+
+- Desktop: wide lab layout with canvas first and controls beside it
+- Mobile: stacked layout with the canvas above controls
+- Preset cards become horizontally scrollable on narrower screens
+
+## Usability Details
+
+- Disable actions when they should not apply, such as disabling step while running
+- Show the active preset and speed tier clearly
+- Short helper copy explaining that each cell looks at its eight neighbors
+
+## Verification Targets
+
+- Conway rule updates are correct
+- Start/pause and single-step work as expected
+- Presets load correctly
+- Editing cells updates the simulation state correctly
+- Layout remains usable after resizing

docs/项目结构图与运行入口说明.md

@@ -0,0 +1,49 @@
+# 项目结构图与运行入口说明（1 分钟版）
+
+## 一、项目结构图
+
+```text
+test/
+├─ index.html                     # 页面入口（直接在浏览器打开）
+├─ styles.css                     # 页面样式
+├─ app.js                         # 生命游戏核心引擎 + UI 交互控制
+├─ tests/
+│  └─ life-demo.test.js           # Node 测试（核心规则与状态逻辑）
+└─ docs/
+   └─ 项目结构图与运行入口说明.md   # 本说明文档
+```
+
+## 二、运行入口
+
+### 1) 浏览器入口（交互演示）
+
+- 入口文件：`index.html`
+- 加载脚本：`index.html` 底部通过 `<script src="./app.js"></script>` 引入引擎与交互逻辑。
+- 打开方式：双击 `index.html`（或在浏览器中打开本地文件）。
+
+### 2) 脚本初始化入口
+
+- `app.js` 在 `DOMContentLoaded` 后执行 `initDemo()`，完成：
+  - 初始状态创建（默认预设、网格尺寸、暂停状态）
+  - 画布渲染与动画循环
+  - 控件事件绑定（开始/暂停、单步、清空、随机、重置预设、速度滑条）
+  - 画布点击/拖拽绘制
+
+## 三、关键代码定位
+
+- 预设图案定义：`app.js:4`
+- 交互初始化入口：`app.js:368`
+- 开始/暂停等主控事件：`app.js:430`
+- Node 导出（供测试复用）：`app.js:540`
+- 测试起始位置：`tests/life-demo.test.js:14`
+
+## 四、测试入口
+
+- 测试文件：`tests/life-demo.test.js`
+- 推荐命令（当前环境可用）：
+
+```bash
+node tests/life-demo.test.js
+```
+
+> 说明：在当前受限环境下，`node --test tests/life-demo.test.js` 可能因子进程权限报 `EPERM`，但直接执行测试文件可正常完成 9 项测试。

index.html

@@ -0,0 +1,196 @@
+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>Conway Life Lab</title>
+  <link rel="stylesheet" href="./styles.css">
+</head>
+<body>
+  <div class="page-shell">
+    <header class="hero">
+      <div class="hero-copy">
+        <p class="eyebrow">CELLULAR AUTOMATA / CONWAY LIFE LAB</p>
+        <h1>观察八个邻居，如何让一张静止网格自己长出秩序。</h1>
+        <p class="hero-intro">
+          这是一个可以直接打开的康威生命游戏演示页：先看规则，再改格子、切预设、调速度，
+          用最经典的元胞自动机感受局部规则如何生成整体行为。
+        </p>
+        <div class="hero-actions">
+          <a class="primary-link" href="#lab">进入实验台</a>
+          <button class="secondary-link" id="load-default-hero" type="button">重新载入默认图案</button>
+        </div>
+        <ul class="hero-pills">
+          <li>默认载入 <strong>脉冲星</strong> 并暂停</li>
+          <li>支持点击与拖拽绘制</li>
+          <li>可切换滑翔机、脉冲星、滑翔机枪</li>
+        </ul>
+      </div>
+      <div class="hero-visual" aria-hidden="true">
+        <div class="signal-board">
+          <div class="signal-layer layer-a"></div>
+          <div class="signal-layer layer-b"></div>
+          <div class="signal-core">
+            <span class="signal-dot live"></span>
+            <span class="signal-dot"></span>
+            <span class="signal-dot live"></span>
+            <span class="signal-dot"></span>
+            <span class="signal-dot live accent"></span>
+            <span class="signal-dot"></span>
+            <span class="signal-dot live"></span>
+            <span class="signal-dot"></span>
+            <span class="signal-dot live"></span>
+          </div>
+        </div>
+        <div class="hero-metrics card-surface">
+          <div class="metric-row">
+            <span class="label">Preset</span>
+            <strong id="hero-pattern">Pulsar</strong>
+          </div>
+          <div class="metric-row">
+            <span class="label">Generation</span>
+            <strong id="hero-generation">0</strong>
+          </div>
+          <div class="metric-row">
+            <span class="label">Live Cells</span>
+            <strong id="hero-live">0</strong>
+          </div>
+        </div>
+      </div>
+    </header>
+
+    <main>
+      <section class="lab-section" id="lab">
+        <div class="section-heading">
+          <p class="eyebrow">Interactive Lab</p>
+          <h2>在画布里编辑生命，控制它的下一代。</h2>
+          <p>
+            每个细胞只看周围 8 个邻居。存活、诞生、死亡这三条规则，会在一代代迭代里形成移动、
+            呼吸、振荡甚至复制的图案。
+          </p>
+        </div>
+
+        <div class="lab-layout">
+          <div class="canvas-panel card-surface">
+            <div class="canvas-toolbar">
+              <div>
+                <p class="label">Simulation Surface</p>
+                <h3>Conway Field</h3>
+              </div>
+              <div class="status-cluster">
+                <span class="status-pill" id="status-text">Paused</span>
+                <span class="speed-pill" id="speed-label">Drift</span>
+              </div>
+            </div>
+
+            <div class="canvas-shell">
+              <canvas id="life-canvas" aria-label="Conway life simulation canvas"></canvas>
+              <div class="canvas-caption">
+                <span id="canvas-hint">点击或拖拽即可绘制细胞</span>
+              </div>
+            </div>
+
+            <div class="canvas-footer">
+              <div class="mini-stat">
+                <span class="label">Generation</span>
+                <strong id="generation-value">0</strong>
+              </div>
+              <div class="mini-stat">
+                <span class="label">Live</span>
+                <strong id="live-value">0</strong>
+              </div>
+              <div class="mini-stat">
+                <span class="label">Preset</span>
+                <strong id="preset-value">Pulsar</strong>
+              </div>
+            </div>
+          </div>
+
+          <aside class="control-panel card-surface">
+            <div class="panel-block">
+              <p class="label">Playback</p>
+              <div class="button-grid">
+                <button class="primary-button" id="play-toggle" type="button">开始演化</button>
+                <button id="step-button" type="button">单步</button>
+                <button id="clear-button" type="button">清空</button>
+                <button id="random-button" type="button">随机</button>
+                <button id="reset-button" type="button">重置预设</button>
+              </div>
+            </div>
+
+            <div class="panel-block">
+              <div class="panel-row">
+                <p class="label">Speed</p>
+                <strong id="speed-readout">1 / 6</strong>
+              </div>
+              <input id="speed-slider" type="range" min="1" max="6" step="1" value="1">
+              <p class="support-copy">从缓慢观察到高速演化，速度越高，图案越容易呈现整体节奏。</p>
+            </div>
+
+            <div class="panel-block">
+              <p class="label">How To Read</p>
+              <ul class="info-list">
+                <li>活细胞周围邻居过少会死亡</li>
+                <li>有 2 或 3 个邻居时会继续存活</li>
+                <li>空白位置恰好有 3 个邻居时会诞生新细胞</li>
+              </ul>
+            </div>
+          </aside>
+        </div>
+      </section>
+
+      <section class="rules-section">
+        <div class="section-heading">
+          <p class="eyebrow">Rule Snapshot</p>
+          <h2>三条规则，就足够让图案产生复杂行为。</h2>
+        </div>
+
+        <div class="rules-grid">
+          <article class="rule-card card-surface">
+            <span class="rule-index">01</span>
+            <h3>存活</h3>
+            <p>一个活细胞如果有 2 或 3 个邻居，就继续存在到下一代。</p>
+          </article>
+          <article class="rule-card card-surface">
+            <span class="rule-index">02</span>
+            <h3>诞生</h3>
+            <p>一个空白位置如果恰好有 3 个邻居，就会在下一代长出新的活细胞。</p>
+          </article>
+          <article class="rule-card card-surface">
+            <span class="rule-index">03</span>
+            <h3>死亡</h3>
+            <p>活细胞邻居少于 2 个会孤独死亡，多于 3 个则会因为拥挤而死亡。</p>
+          </article>
+        </div>
+      </section>
+
+      <section class="presets-section">
+        <div class="section-heading">
+          <p class="eyebrow">Preset Patterns</p>
+          <h2>一键加载经典结构，观察它们如何移动、振荡与扩散。</h2>
+        </div>
+
+        <div class="preset-grid">
+          <button class="preset-card card-surface active" data-pattern="pulsar" type="button">
+            <span class="preset-tag">Default</span>
+            <h3>脉冲星</h3>
+            <p>经典振荡图案，适合观察规则如何形成节律。</p>
+          </button>
+          <button class="preset-card card-surface" data-pattern="glider" type="button">
+            <span class="preset-tag">Mover</span>
+            <h3>滑翔机</h3>
+            <p>最著名的移动结构，会沿对角线不断前进。</p>
+          </button>
+          <button class="preset-card card-surface" data-pattern="gosperGliderGun" type="button">
+            <span class="preset-tag">Emitter</span>
+            <h3>滑翔机枪</h3>
+            <p>持续喷射滑翔机的结构，展示局部规则如何形成长期模式。</p>
+          </button>
+        </div>
+      </section>
+    </main>
+  </div>
+
+  <script src="./app.js"></script>
+</body>
+</html>

styles.css

@@ -0,0 +1,667 @@
+:root {
+  --bg: #07111f;
+  --bg-soft: rgba(11, 22, 38, 0.88);
+  --panel: rgba(10, 20, 35, 0.72);
+  --panel-strong: rgba(12, 24, 40, 0.92);
+  --line: rgba(116, 175, 199, 0.18);
+  --line-strong: rgba(143, 220, 232, 0.34);
+  --text: #edf8fb;
+  --muted: #98b6c5;
+  --accent: #73f0dd;
+  --accent-strong: #befc7d;
+  --shadow: 0 24px 80px rgba(0, 0, 0, 0.32);
+  --radius-xl: 30px;
+  --radius-lg: 22px;
+  --radius-md: 16px;
+  --heading-font: "Microsoft YaHei UI", "Noto Sans SC", sans-serif;
+  --body-font: "Microsoft YaHei", "Noto Sans SC", sans-serif;
+}
+
+* {
+  box-sizing: border-box;
+}
+
+html {
+  scroll-behavior: smooth;
+}
+
+body {
+  margin: 0;
+  min-height: 100vh;
+  color: var(--text);
+  font-family: var(--body-font);
+  background:
+    radial-gradient(circle at top left, rgba(45, 109, 162, 0.22), transparent 30%),
+    radial-gradient(circle at 80% 10%, rgba(115, 240, 221, 0.16), transparent 28%),
+    radial-gradient(circle at bottom right, rgba(190, 252, 125, 0.12), transparent 24%),
+    linear-gradient(180deg, #07111f 0%, #040914 55%, #07101d 100%);
+  overflow-x: hidden;
+}
+
+body::before,
+body::after {
+  content: "";
+  position: fixed;
+  inset: 0;
+  pointer-events: none;
+  z-index: -1;
+}
+
+body::before {
+  background-image:
+    linear-gradient(rgba(255, 255, 255, 0.028) 1px, transparent 1px),
+    linear-gradient(90deg, rgba(255, 255, 255, 0.028) 1px, transparent 1px);
+  background-size: 42px 42px;
+  mask-image: radial-gradient(circle at center, black 35%, transparent 88%);
+}
+
+body::after {
+  opacity: 0.18;
+  background:
+    radial-gradient(circle at 20% 20%, rgba(115, 240, 221, 0.4), transparent 12%),
+    radial-gradient(circle at 75% 25%, rgba(190, 252, 125, 0.25), transparent 10%),
+    radial-gradient(circle at 50% 80%, rgba(115, 167, 240, 0.18), transparent 14%);
+  filter: blur(50px);
+}
+
+a,
+button,
+input {
+  font: inherit;
+}
+
+button {
+  border: 0;
+  cursor: pointer;
+}
+
+.page-shell {
+  width: 100%;
+  max-width: 1240px;
+  margin: 0 auto;
+  padding: 32px 16px 72px;
+}
+
+.hero,
+.lab-section,
+.rules-section,
+.presets-section {
+  position: relative;
+}
+
+.hero-copy,
+.hero-visual,
+.canvas-panel,
+.control-panel,
+.rule-card,
+.preset-card {
+  min-width: 0;
+}
+
+.hero {
+  display: grid;
+  grid-template-columns: minmax(0, 1.15fr) minmax(320px, 0.85fr);
+  gap: 32px;
+  align-items: center;
+  min-height: min(92vh, 860px);
+  padding: 32px 0 56px;
+}
+
+.hero-copy h1,
+.section-heading h2,
+.canvas-toolbar h3,
+.rule-card h3,
+.preset-card h3 {
+  margin: 0;
+  font-family: var(--heading-font);
+  letter-spacing: -0.04em;
+}
+
+.hero-copy h1 {
+  max-width: 11ch;
+  font-size: clamp(3rem, 8vw, 6.8rem);
+  line-height: 0.95;
+  text-wrap: balance;
+  word-break: break-word;
+}
+
+.eyebrow,
+.label {
+  margin: 0;
+  color: var(--accent);
+  letter-spacing: 0.18em;
+  text-transform: uppercase;
+  font-size: 0.72rem;
+}
+
+.hero-intro,
+.section-heading p,
+.support-copy,
+.info-list,
+.rule-card p,
+.preset-card p {
+  color: var(--muted);
+}
+
+.hero-intro {
+  max-width: 36rem;
+  margin: 24px 0 0;
+  font-size: 1.06rem;
+  line-height: 1.75;
+}
+
+.hero-actions {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 14px;
+  margin-top: 28px;
+}
+
+.primary-link,
+.secondary-link,
+.button-grid button {
+  border-radius: 999px;
+  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease, background 180ms ease;
+}
+
+.primary-link,
+.secondary-link {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  min-height: 52px;
+  padding: 0 24px;
+  text-decoration: none;
+}
+
+.primary-link {
+  color: #05232a;
+  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-strong) 100%);
+  box-shadow: 0 18px 38px rgba(115, 240, 221, 0.25);
+}
+
+.secondary-link {
+  color: var(--text);
+  border: 1px solid var(--line-strong);
+  background: rgba(255, 255, 255, 0.04);
+}
+
+.hero-pills {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 12px;
+  margin: 30px 0 0;
+  padding: 0;
+  list-style: none;
+}
+
+.hero-pills li {
+  padding: 12px 16px;
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  border-radius: 999px;
+  background: rgba(255, 255, 255, 0.04);
+  color: var(--muted);
+  backdrop-filter: blur(12px);
+}
+
+.hero-visual {
+  position: relative;
+  display: grid;
+  place-items: center;
+  min-height: 560px;
+}
+
+.signal-board {
+  position: relative;
+  width: min(100%, 520px);
+  aspect-ratio: 1;
+  border-radius: 36px;
+  background:
+    linear-gradient(180deg, rgba(9, 18, 31, 0.9), rgba(10, 21, 33, 0.72)),
+    radial-gradient(circle at center, rgba(115, 240, 221, 0.15), transparent 58%);
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  overflow: hidden;
+  box-shadow: var(--shadow);
+}
+
+.signal-board::before {
+  content: "";
+  position: absolute;
+  inset: 0;
+  background-image:
+    linear-gradient(rgba(115, 240, 221, 0.06) 1px, transparent 1px),
+    linear-gradient(90deg, rgba(115, 240, 221, 0.06) 1px, transparent 1px);
+  background-size: 10% 10%;
+}
+
+.signal-layer {
+  position: absolute;
+  inset: 14%;
+  border-radius: 28px;
+  border: 1px solid rgba(190, 252, 125, 0.18);
+}
+
+.layer-a {
+  animation: drift 14s linear infinite;
+}
+
+.layer-b {
+  inset: 22%;
+  border-color: rgba(115, 240, 221, 0.24);
+  animation: driftReverse 18s linear infinite;
+}
+
+.signal-core {
+  position: absolute;
+  inset: 50%;
+  width: 40%;
+  height: 40%;
+  display: grid;
+  grid-template-columns: repeat(3, 1fr);
+  gap: 14px;
+  transform: translate(-50%, -50%);
+}
+
+.signal-dot {
+  border-radius: 14px;
+  background: rgba(255, 255, 255, 0.04);
+  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.05);
+}
+
+.signal-dot.live {
+  background: linear-gradient(135deg, rgba(115, 240, 221, 0.94), rgba(190, 252, 125, 0.94));
+  box-shadow:
+    0 0 28px rgba(115, 240, 221, 0.42),
+    inset 0 0 18px rgba(255, 255, 255, 0.22);
+  animation: pulseDot 3.6s ease-in-out infinite;
+}
+
+.signal-dot.accent {
+  animation-delay: 0.8s;
+}
+
+.hero-metrics {
+  position: absolute;
+  right: 0;
+  bottom: 24px;
+  width: min(300px, 85%);
+}
+
+.card-surface {
+  padding: 22px;
+  border-radius: var(--radius-xl);
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  background:
+    linear-gradient(180deg, rgba(14, 24, 38, 0.82), rgba(8, 16, 29, 0.78)),
+    rgba(255, 255, 255, 0.02);
+  box-shadow: var(--shadow);
+  backdrop-filter: blur(20px);
+}
+
+.metric-row,
+.panel-row,
+.canvas-footer {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+}
+
+.metric-row + .metric-row {
+  margin-top: 16px;
+}
+
+.metric-row strong,
+.mini-stat strong,
+.panel-row strong {
+  font-family: var(--heading-font);
+  font-size: 1.25rem;
+}
+
+.lab-section,
+.rules-section,
+.presets-section {
+  padding-top: 48px;
+}
+
+.section-heading {
+  max-width: 52rem;
+  margin-bottom: 28px;
+}
+
+.section-heading h2 {
+  font-size: clamp(2.1rem, 4vw, 3.6rem);
+  line-height: 0.98;
+  margin-top: 10px;
+}
+
+.section-heading p {
+  margin: 14px 0 0;
+  line-height: 1.75;
+}
+
+.lab-layout {
+  display: grid;
+  grid-template-columns: minmax(0, 1.25fr) minmax(320px, 0.75fr);
+  gap: 22px;
+}
+
+.canvas-panel,
+.control-panel {
+  min-height: 100%;
+}
+
+.canvas-toolbar {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 16px;
+}
+
+.canvas-toolbar h3 {
+  margin-top: 6px;
+  font-size: 1.8rem;
+}
+
+.status-cluster {
+  display: flex;
+  flex-wrap: wrap;
+  justify-content: flex-end;
+  gap: 10px;
+}
+
+.status-pill,
+.speed-pill,
+.preset-tag {
+  display: inline-flex;
+  align-items: center;
+  min-height: 36px;
+  padding: 0 14px;
+  border-radius: 999px;
+  font-size: 0.86rem;
+  letter-spacing: 0.08em;
+  text-transform: uppercase;
+}
+
+.status-pill {
+  color: var(--bg);
+  background: linear-gradient(135deg, var(--accent) 0%, rgba(115, 240, 221, 0.72) 100%);
+}
+
+.status-pill.running {
+  background: linear-gradient(135deg, var(--accent-strong) 0%, var(--accent) 100%);
+}
+
+.speed-pill,
+.preset-tag {
+  border: 1px solid var(--line-strong);
+  color: var(--text);
+  background: rgba(255, 255, 255, 0.05);
+}
+
+.canvas-shell {
+  position: relative;
+  margin-top: 22px;
+  padding: 18px;
+  border-radius: 26px;
+  background:
+    linear-gradient(180deg, rgba(6, 13, 24, 0.94), rgba(5, 11, 19, 0.9)),
+    rgba(255, 255, 255, 0.02);
+  border: 1px solid rgba(255, 255, 255, 0.06);
+}
+
+#life-canvas {
+  display: block;
+  width: 100%;
+  aspect-ratio: 1;
+  border-radius: 18px;
+  background:
+    radial-gradient(circle at top left, rgba(115, 240, 221, 0.08), transparent 24%),
+    linear-gradient(180deg, rgba(6, 16, 27, 0.98), rgba(5, 12, 22, 0.98));
+  cursor: crosshair;
+}
+
+.canvas-caption {
+  display: flex;
+  justify-content: space-between;
+  margin-top: 12px;
+  color: var(--muted);
+  font-size: 0.94rem;
+}
+
+.canvas-footer {
+  gap: 16px;
+  margin-top: 18px;
+}
+
+.mini-stat {
+  flex: 1 1 0;
+  padding: 16px;
+  border-radius: 18px;
+  background: rgba(255, 255, 255, 0.03);
+  border: 1px solid rgba(255, 255, 255, 0.05);
+}
+
+.mini-stat .label {
+  display: block;
+  margin-bottom: 10px;
+}
+
+.panel-block + .panel-block {
+  margin-top: 22px;
+}
+
+.button-grid {
+  display: grid;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 12px;
+  margin-top: 14px;
+}
+
+.button-grid button,
+.preset-card {
+  color: var(--text);
+  padding: 14px 16px;
+  border: 1px solid rgba(255, 255, 255, 0.09);
+  background: rgba(255, 255, 255, 0.04);
+}
+
+.button-grid button:hover,
+.button-grid button:focus-visible,
+.primary-link:hover,
+.secondary-link:hover,
+.preset-card:hover,
+.preset-card:focus-visible {
+  transform: translateY(-2px);
+  box-shadow: 0 18px 40px rgba(0, 0, 0, 0.16);
+}
+
+.button-grid .primary-button {
+  grid-column: span 2;
+  color: #04131e;
+  background: linear-gradient(135deg, var(--accent-strong), var(--accent));
+}
+
+.button-grid button:disabled {
+  cursor: not-allowed;
+  opacity: 0.45;
+  transform: none;
+  box-shadow: none;
+}
+
+#speed-slider {
+  width: 100%;
+  margin-top: 12px;
+  accent-color: var(--accent);
+}
+
+.support-copy {
+  margin: 12px 0 0;
+  line-height: 1.65;
+}
+
+.info-list {
+  margin: 14px 0 0;
+  padding-left: 18px;
+  line-height: 1.75;
+}
+
+.rules-grid,
+.preset-grid {
+  display: grid;
+  gap: 18px;
+}
+
+.rules-grid {
+  grid-template-columns: repeat(3, minmax(0, 1fr));
+}
+
+.rule-card {
+  min-height: 220px;
+}
+
+.rule-index {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  width: 52px;
+  height: 52px;
+  border-radius: 16px;
+  font-family: var(--heading-font);
+  color: var(--bg);
+  background: linear-gradient(135deg, rgba(115, 240, 221, 0.94), rgba(190, 252, 125, 0.88));
+}
+
+.rule-card h3,
+.preset-card h3 {
+  margin-top: 20px;
+  font-size: 1.5rem;
+}
+
+.rule-card p,
+.preset-card p {
+  margin: 12px 0 0;
+  line-height: 1.75;
+}
+
+.preset-grid {
+  grid-template-columns: repeat(3, minmax(0, 1fr));
+}
+
+.preset-card {
+  text-align: left;
+  border-radius: var(--radius-lg);
+}
+
+.preset-card.active {
+  border-color: rgba(115, 240, 221, 0.72);
+  background:
+    linear-gradient(180deg, rgba(14, 26, 39, 0.94), rgba(8, 17, 29, 0.84)),
+    rgba(255, 255, 255, 0.04);
+  box-shadow: 0 0 0 1px rgba(115, 240, 221, 0.24), var(--shadow);
+}
+
+@keyframes pulseDot {
+  0%,
+  100% {
+    transform: scale(0.94);
+    opacity: 0.72;
+  }
+  50% {
+    transform: scale(1.04);
+    opacity: 1;
+  }
+}
+
+@keyframes drift {
+  from {
+    transform: rotate(0deg);
+  }
+  to {
+    transform: rotate(360deg);
+  }
+}
+
+@keyframes driftReverse {
+  from {
+    transform: rotate(0deg) scale(1.02);
+  }
+  to {
+    transform: rotate(-360deg) scale(1.02);
+  }
+}
+
+@media (max-width: 980px) {
+  .hero,
+  .lab-layout,
+  .rules-grid,
+  .preset-grid {
+    grid-template-columns: 1fr;
+  }
+
+  .hero {
+    min-height: auto;
+    padding-top: 20px;
+  }
+
+  .hero-copy h1 {
+    max-width: none;
+  }
+
+  .hero-visual {
+    min-height: 420px;
+  }
+
+  .hero-metrics {
+    position: static;
+    width: 100%;
+    margin-top: 18px;
+  }
+}
+
+@media (max-width: 720px) {
+  .page-shell {
+    padding: 18px 10px 56px;
+  }
+
+  .canvas-footer,
+  .button-grid {
+    grid-template-columns: 1fr;
+  }
+
+  .canvas-footer {
+    flex-direction: column;
+  }
+
+  .button-grid .primary-button {
+    grid-column: auto;
+  }
+
+  .hero-actions,
+  .status-cluster {
+    flex-direction: column;
+    align-items: stretch;
+  }
+
+  .hero-copy h1 {
+    max-width: 9ch;
+    font-size: clamp(2.2rem, 11vw, 3rem);
+    line-height: 0.98;
+  }
+
+  .primary-link,
+  .secondary-link {
+    width: 100%;
+  }
+
+  .preset-grid {
+    display: flex;
+    overflow-x: auto;
+    padding-bottom: 6px;
+    scroll-snap-type: x proximity;
+  }
+
+  .preset-card {
+    min-width: min(300px, 84vw);
+    scroll-snap-align: start;
+  }
+}

tests/life-demo.test.js

@@ -0,0 +1,148 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+
+function loadApi() {
+  let api;
+
+  assert.doesNotThrow(() => {
+    api = require('../app.js');
+  }, 'expected app.js to export the Conway helpers');
+
+  return api;
+}
+
+test('blinker rotates after one generation', () => {
+  const { createEmptyGrid, stepGrid } = loadApi();
+  const grid = createEmptyGrid(5, 5);
+
+  grid[2][1] = 1;
+  grid[2][2] = 1;
+  grid[2][3] = 1;
+
+  const next = stepGrid(grid);
+
+  assert.deepEqual(next, [
+    [0, 0, 0, 0, 0],
+    [0, 0, 1, 0, 0],
+    [0, 0, 1, 0, 0],
+    [0, 0, 1, 0, 0],
+    [0, 0, 0, 0, 0],
+  ]);
+});
+
+test('block stays stable across generations', () => {
+  const { createEmptyGrid, stepGrid } = loadApi();
+  const grid = createEmptyGrid(4, 4);
+
+  grid[1][1] = 1;
+  grid[1][2] = 1;
+  grid[2][1] = 1;
+  grid[2][2] = 1;
+
+  assert.deepEqual(stepGrid(grid), grid);
+});
+
+test('stampPattern places the glider cells inside the grid', () => {
+  const { createEmptyGrid, stampPattern, PATTERNS } = loadApi();
+  const grid = createEmptyGrid(6, 6);
+
+  stampPattern(grid, PATTERNS.glider, 1, 1);
+
+  assert.equal(grid[1][2], 1);
+  assert.equal(grid[2][3], 1);
+  assert.equal(grid[3][1], 1);
+  assert.equal(grid[3][2], 1);
+  assert.equal(grid[3][3], 1);
+});
+
+test('createInitialState seeds the default preset and starts paused', () => {
+  const { createInitialState } = loadApi();
+  const state = createInitialState({
+    rows: 20,
+    cols: 20,
+    defaultPattern: 'pulsar',
+  });
+
+  assert.equal(state.running, false);
+  assert.equal(state.selectedPattern, 'pulsar');
+  assert.equal(state.generation, 0);
+  assert.ok(state.liveCount > 0);
+});
+
+test('toggleCell flips a single cell without mutating the original grid', () => {
+  const { createEmptyGrid, toggleCell } = loadApi();
+  const grid = createEmptyGrid(3, 3);
+  const next = toggleCell(grid, 1, 1);
+
+  assert.equal(grid[1][1], 0);
+  assert.equal(next[1][1], 1);
+});
+
+test('applyPreset replaces the grid, pauses playback, and resets generation', () => {
+  const { applyPreset, createInitialState } = loadApi();
+  const state = {
+    ...createInitialState({ rows: 30, cols: 30, defaultPattern: 'glider' }),
+    generation: 12,
+    running: true,
+  };
+
+  const next = applyPreset(state, 'gosperGliderGun');
+
+  assert.equal(next.running, false);
+  assert.equal(next.generation, 0);
+  assert.equal(next.selectedPattern, 'gosperGliderGun');
+  assert.ok(next.liveCount > 0);
+});
+
+test('advanceState steps the grid and increments generation', () => {
+  const { advanceState, createEmptyGrid } = loadApi();
+  const grid = createEmptyGrid(5, 5);
+
+  grid[2][1] = 1;
+  grid[2][2] = 1;
+  grid[2][3] = 1;
+
+  const next = advanceState({
+    cols: 5,
+    generation: 0,
+    grid: grid,
+    liveCount: 3,
+    rows: 5,
+    running: true,
+    selectedPattern: 'custom',
+    speed: 1,
+  });
+
+  assert.equal(next.generation, 1);
+  assert.equal(next.liveCount, 3);
+  assert.equal(next.grid[1][2], 1);
+  assert.equal(next.grid[2][2], 1);
+  assert.equal(next.grid[3][2], 1);
+});
+
+test('randomizeGrid respects probability extremes', () => {
+  const { createEmptyGrid, randomizeGrid } = loadApi();
+  const grid = createEmptyGrid(2, 3);
+
+  assert.deepEqual(randomizeGrid(grid, 0), [
+    [0, 0, 0],
+    [0, 0, 0],
+  ]);
+  assert.deepEqual(randomizeGrid(grid, 1), [
+    [1, 1, 1],
+    [1, 1, 1],
+  ]);
+});
+
+test('setSpeed returns a copied state with a readable label', () => {
+  const { createInitialState, getSpeedDelay, getSpeedLabel, setSpeed } = loadApi();
+  const state = createInitialState({ rows: 10, cols: 10, defaultPattern: 'glider' });
+  const next = setSpeed(state, 4);
+
+  assert.notEqual(next, state);
+  assert.equal(next.speed, 4);
+  assert.equal(getSpeedLabel(next.speed), 'Hyper');
+  assert.equal(getSpeedLabel(1), 'Drift');
+  assert.equal(getSpeedDelay(1), 520);
+  assert.equal(getSpeedDelay(6), 60);
+});