commit 2833d9610ae5bf52b54809e9f96a7804361ac8b7
Author: Spencer <spencer@sketchferret.com>
Date:   Tue May 5 10:52:28 2026 -0400

    Initial Tictactics proof of concept

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..20d6b3d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,26 @@
+# Dependencies
+node_modules/
+
+# Build output
+dist/
+build/
+out/
+
+# Local env and editor state
+.env
+.env.*
+!.env.example
+.vscode/
+.idea/
+
+# Logs
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+
+# OS files
+.DS_Store
+Thumbs.db
+
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..b3b6f43
--- /dev/null
+++ b/README.md
@@ -0,0 +1,19 @@
+# Tictactics
+
+A notepad-playable browser game that combines Tic Tac Toe's line-making goal with a small capture mechanic.
+
+## Rules
+
+- Two players alternate placing `X` and `O` on empty cells.
+- The board is `5 x 5`.
+- After placing a mark, enemy marks trapped in a straight line between the new mark and another friendly mark are captured and removed.
+- Captures can happen in any of the eight directions.
+- First player to make `4 in a row` wins.
+- If the board fills with no winner, the game is a draw.
+
+## Run
+
+Open `index.html` in a browser.
+
+No build step is required.
+
diff --git a/game.js b/game.js
new file mode 100644
index 0000000..5b286f1
--- /dev/null
+++ b/game.js
@@ -0,0 +1,228 @@
+const size = 5;
+const target = 4;
+const empty = "";
+const directions = [
+  [-1, -1],
+  [-1, 0],
+  [-1, 1],
+  [0, -1],
+  [0, 1],
+  [1, -1],
+  [1, 0],
+  [1, 1],
+];
+
+const boardElement = document.querySelector("#board");
+const messageElement = document.querySelector("#message");
+const turnBadge = document.querySelector("#turnBadge");
+const resetButton = document.querySelector("#resetButton");
+const xCapturesElement = document.querySelector("#xCaptures");
+const oCapturesElement = document.querySelector("#oCaptures");
+const moveList = document.querySelector("#moveList");
+
+let board;
+let currentPlayer;
+let captures;
+let gameOver;
+let moveNumber;
+let winningCells;
+
+function createBoard() {
+  return Array.from({ length: size }, () => Array(size).fill(empty));
+}
+
+function setupGame() {
+  board = createBoard();
+  currentPlayer = "X";
+  captures = { X: 0, O: 0 };
+  gameOver = false;
+  moveNumber = 0;
+  winningCells = [];
+  moveList.innerHTML = "";
+  render();
+  setMessage("Trap enemy marks between your marks. First to four wins.");
+}
+
+function render() {
+  boardElement.innerHTML = "";
+  boardElement.style.setProperty("--size", size);
+
+  for (let row = 0; row < size; row += 1) {
+    for (let col = 0; col < size; col += 1) {
+      const cell = document.createElement("button");
+      cell.className = "cell";
+      cell.type = "button";
+      cell.role = "gridcell";
+      cell.dataset.row = row;
+      cell.dataset.col = col;
+      cell.setAttribute("aria-label", cellLabel(row, col));
+      cell.disabled = gameOver || board[row][col] !== empty;
+
+      if (winningCells.some(([winRow, winCol]) => winRow === row && winCol === col)) {
+        cell.classList.add("winning");
+      }
+
+      if (board[row][col]) {
+        const mark = document.createElement("span");
+        mark.className = `mark mark-${board[row][col].toLowerCase()}`;
+        mark.textContent = board[row][col];
+        cell.append(mark);
+      }
+
+      cell.addEventListener("click", () => playMove(row, col));
+      boardElement.append(cell);
+    }
+  }
+
+  turnBadge.textContent = gameOver ? "Game over" : `${currentPlayer} to play`;
+  turnBadge.className = `turn-badge player-${currentPlayer.toLowerCase()}`;
+  xCapturesElement.textContent = captures.X;
+  oCapturesElement.textContent = captures.O;
+}
+
+function cellLabel(row, col) {
+  const mark = board[row][col];
+  const position = `row ${row + 1}, column ${col + 1}`;
+  return mark ? `${mark} at ${position}` : `Empty cell at ${position}`;
+}
+
+function playMove(row, col) {
+  if (gameOver || board[row][col] !== empty) {
+    return;
+  }
+
+  moveNumber += 1;
+  board[row][col] = currentPlayer;
+  const captured = captureFrom(row, col, currentPlayer);
+  captures[currentPlayer] += captured.length;
+
+  const win = findWin(currentPlayer);
+  addMove(row, col, captured.length);
+
+  if (win.length > 0) {
+    winningCells = win;
+    gameOver = true;
+    setMessage(`${currentPlayer} wins with four in a row.`);
+    render();
+    return;
+  }
+
+  if (isDraw()) {
+    gameOver = true;
+    setMessage("Draw. The board is full.");
+    render();
+    return;
+  }
+
+  currentPlayer = opponentOf(currentPlayer);
+  setMessage(captured.length > 0
+    ? `${opponentOf(currentPlayer)} captured ${captured.length}. ${currentPlayer} to play.`
+    : `${currentPlayer} to play.`
+  );
+  render();
+  flashCapturedCells(captured);
+}
+
+function captureFrom(row, col, player) {
+  const opponent = opponentOf(player);
+  const captured = [];
+
+  for (const [rowStep, colStep] of directions) {
+    const candidates = [];
+    let nextRow = row + rowStep;
+    let nextCol = col + colStep;
+
+    while (isInside(nextRow, nextCol) && board[nextRow][nextCol] === opponent) {
+      candidates.push([nextRow, nextCol]);
+      nextRow += rowStep;
+      nextCol += colStep;
+    }
+
+    if (candidates.length > 0 && isInside(nextRow, nextCol) && board[nextRow][nextCol] === player) {
+      captured.push(...candidates);
+    }
+  }
+
+  for (const [captureRow, captureCol] of captured) {
+    board[captureRow][captureCol] = empty;
+  }
+
+  return captured;
+}
+
+function findWin(player) {
+  const axes = [
+    [0, 1],
+    [1, 0],
+    [1, 1],
+    [1, -1],
+  ];
+
+  for (let row = 0; row < size; row += 1) {
+    for (let col = 0; col < size; col += 1) {
+      if (board[row][col] !== player) {
+        continue;
+      }
+
+      for (const [rowStep, colStep] of axes) {
+        const cells = [[row, col]];
+
+        for (let index = 1; index < target; index += 1) {
+          const nextRow = row + rowStep * index;
+          const nextCol = col + colStep * index;
+
+          if (!isInside(nextRow, nextCol) || board[nextRow][nextCol] !== player) {
+            break;
+          }
+
+          cells.push([nextRow, nextCol]);
+        }
+
+        if (cells.length === target) {
+          return cells;
+        }
+      }
+    }
+  }
+
+  return [];
+}
+
+function isDraw() {
+  return board.every((row) => row.every((cell) => cell !== empty));
+}
+
+function opponentOf(player) {
+  return player === "X" ? "O" : "X";
+}
+
+function isInside(row, col) {
+  return row >= 0 && row < size && col >= 0 && col < size;
+}
+
+function addMove(row, col, captureCount) {
+  const item = document.createElement("li");
+  const captureText = captureCount === 0 ? "" : `, captured ${captureCount}`;
+  item.textContent = `${moveNumber}. ${currentPlayer} to ${row + 1},${col + 1}${captureText}`;
+  moveList.prepend(item);
+}
+
+function setMessage(text) {
+  messageElement.textContent = text;
+}
+
+function flashCapturedCells(captured) {
+  for (const [row, col] of captured) {
+    const cell = boardElement.querySelector(`[data-row="${row}"][data-col="${col}"]`);
+    if (!cell) {
+      continue;
+    }
+
+    cell.classList.add("captured");
+    window.setTimeout(() => cell.classList.remove("captured"), 380);
+  }
+}
+
+resetButton.addEventListener("click", setupGame);
+setupGame();
+
diff --git a/index.html b/index.html
new file mode 100644
index 0000000..f31248f
--- /dev/null
+++ b/index.html
@@ -0,0 +1,54 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <title>Tictactics</title>
+    <link rel="stylesheet" href="styles.css">
+  </head>
+  <body>
+    <main class="app" aria-labelledby="game-title">
+      <section class="play-area">
+        <header class="topbar">
+          <div>
+            <p class="eyebrow">capture tic tac toe</p>
+            <h1 id="game-title">Tictactics</h1>
+          </div>
+          <button id="resetButton" class="icon-button" type="button" aria-label="Restart game" title="Restart">
+            <span aria-hidden="true">↻</span>
+          </button>
+        </header>
+
+        <div class="status-row" aria-live="polite">
+          <div id="turnBadge" class="turn-badge player-x">X to play</div>
+          <div id="message" class="message">Trap enemy marks between your marks. First to four wins.</div>
+        </div>
+
+        <div id="board" class="board" role="grid" aria-label="Tictactics board"></div>
+      </section>
+
+      <aside class="side-panel" aria-label="Game details">
+        <div class="score-row">
+          <div class="score-box">
+            <span class="score-label">X captures</span>
+            <strong id="xCaptures">0</strong>
+          </div>
+          <div class="score-box">
+            <span class="score-label">O captures</span>
+            <strong id="oCaptures">0</strong>
+          </div>
+        </div>
+
+        <div class="rule-card">
+          <h2>Rule</h2>
+          <p>Place a mark on an empty cell. Any enemy marks trapped in a straight line between your marks are removed.</p>
+        </div>
+
+        <ol id="moveList" class="move-list" aria-label="Move history"></ol>
+      </aside>
+    </main>
+
+    <script src="game.js"></script>
+  </body>
+</html>
+
diff --git a/styles.css b/styles.css
new file mode 100644
index 0000000..a4fc8ad
--- /dev/null
+++ b/styles.css
@@ -0,0 +1,310 @@
+:root {
+  color-scheme: light;
+  --ink: #161616;
+  --muted: #62635f;
+  --paper: #f9f6ee;
+  --panel: #fffdfa;
+  --line: #252525;
+  --grid: #d9d1bf;
+  --x: #cb3d3d;
+  --o: #216e8d;
+  --x-soft: #ffe1df;
+  --o-soft: #d9f1f8;
+  --focus: #6750a4;
+  --shadow: 0 20px 50px rgba(30, 25, 15, 0.12);
+}
+
+* {
+  box-sizing: border-box;
+}
+
+body {
+  margin: 0;
+  min-height: 100vh;
+  color: var(--ink);
+  background:
+    linear-gradient(rgba(22, 22, 22, 0.035) 1px, transparent 1px),
+    linear-gradient(90deg, rgba(22, 22, 22, 0.035) 1px, transparent 1px),
+    var(--paper);
+  background-size: 32px 32px;
+  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
+}
+
+button {
+  font: inherit;
+}
+
+.app {
+  width: min(1120px, calc(100vw - 32px));
+  min-height: 100vh;
+  margin: 0 auto;
+  display: grid;
+  grid-template-columns: minmax(0, 1fr) 320px;
+  gap: 28px;
+  align-items: center;
+  padding: 32px 0;
+}
+
+.play-area,
+.side-panel {
+  background: rgba(255, 253, 250, 0.86);
+  border: 1px solid rgba(37, 37, 37, 0.12);
+  box-shadow: var(--shadow);
+}
+
+.play-area {
+  padding: 24px;
+}
+
+.side-panel {
+  padding: 18px;
+}
+
+.topbar,
+.status-row,
+.score-row {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 16px;
+}
+
+.eyebrow {
+  margin: 0 0 4px;
+  color: var(--muted);
+  font-size: 0.78rem;
+  font-weight: 800;
+  text-transform: uppercase;
+}
+
+h1 {
+  margin: 0;
+  font-size: clamp(2.2rem, 4.8rem, 5rem);
+  line-height: 0.92;
+}
+
+.icon-button {
+  width: 44px;
+  height: 44px;
+  display: inline-grid;
+  place-items: center;
+  border: 2px solid var(--line);
+  border-radius: 8px;
+  color: var(--ink);
+  background: var(--panel);
+  cursor: pointer;
+  transition: transform 150ms ease, background 150ms ease;
+}
+
+.icon-button:hover {
+  background: #eee6d6;
+  transform: translateY(-1px);
+}
+
+.icon-button:focus-visible,
+.cell:focus-visible {
+  outline: 3px solid var(--focus);
+  outline-offset: 3px;
+}
+
+.status-row {
+  margin: 24px 0 18px;
+}
+
+.turn-badge {
+  min-width: 104px;
+  padding: 9px 12px;
+  border: 2px solid currentColor;
+  border-radius: 8px;
+  font-weight: 900;
+  text-align: center;
+}
+
+.player-x {
+  color: var(--x);
+  background: var(--x-soft);
+}
+
+.player-o {
+  color: var(--o);
+  background: var(--o-soft);
+}
+
+.message {
+  color: var(--muted);
+  font-size: 0.95rem;
+  text-align: right;
+}
+
+.board {
+  aspect-ratio: 1;
+  width: min(100%, 620px);
+  margin: 0 auto;
+  display: grid;
+  grid-template-columns: repeat(5, 1fr);
+  grid-template-rows: repeat(5, 1fr);
+  border: 3px solid var(--line);
+  background: var(--line);
+  gap: 3px;
+}
+
+.cell {
+  min-width: 0;
+  border: 0;
+  display: grid;
+  place-items: center;
+  background: var(--panel);
+  color: var(--ink);
+  cursor: pointer;
+  position: relative;
+  isolation: isolate;
+}
+
+.cell::before {
+  content: "";
+  position: absolute;
+  inset: 13%;
+  border: 2px dashed rgba(37, 37, 37, 0.14);
+  border-radius: 50%;
+  opacity: 0;
+  transition: opacity 120ms ease;
+}
+
+.cell:hover::before {
+  opacity: 1;
+}
+
+.cell[disabled] {
+  cursor: default;
+}
+
+.mark {
+  display: grid;
+  place-items: center;
+  width: 72%;
+  height: 72%;
+  border-radius: 50%;
+  font-size: clamp(2rem, 8vw, 4.4rem);
+  font-weight: 950;
+  line-height: 1;
+  transform: scale(0.96);
+  animation: pop 180ms ease-out;
+}
+
+.mark-x {
+  color: var(--x);
+}
+
+.mark-o {
+  color: var(--o);
+}
+
+.cell.captured {
+  animation: capture 360ms ease-out;
+}
+
+.cell.winning {
+  background: #fff0aa;
+}
+
+.score-row {
+  margin-bottom: 16px;
+}
+
+.score-box {
+  flex: 1;
+  padding: 14px;
+  border: 1px solid rgba(37, 37, 37, 0.14);
+  border-radius: 8px;
+  background: var(--panel);
+}
+
+.score-label {
+  display: block;
+  color: var(--muted);
+  font-size: 0.76rem;
+  font-weight: 800;
+  text-transform: uppercase;
+}
+
+.score-box strong {
+  display: block;
+  margin-top: 4px;
+  font-size: 2rem;
+}
+
+.rule-card {
+  padding: 14px;
+  border: 1px solid rgba(37, 37, 37, 0.14);
+  border-radius: 8px;
+  background: #f5efe2;
+}
+
+.rule-card h2 {
+  margin: 0 0 8px;
+  font-size: 1rem;
+}
+
+.rule-card p {
+  margin: 0;
+  color: var(--muted);
+  line-height: 1.45;
+}
+
+.move-list {
+  max-height: 320px;
+  margin: 16px 0 0;
+  padding: 0 0 0 24px;
+  overflow: auto;
+  color: var(--muted);
+}
+
+.move-list li {
+  margin-bottom: 8px;
+  padding-left: 4px;
+}
+
+@keyframes pop {
+  from {
+    opacity: 0;
+    transform: scale(0.66);
+  }
+}
+
+@keyframes capture {
+  35% {
+    background: #202020;
+  }
+}
+
+@media (max-width: 860px) {
+  .app {
+    min-height: auto;
+    grid-template-columns: 1fr;
+    align-items: start;
+    padding: 18px 0;
+  }
+
+  .play-area,
+  .side-panel {
+    padding: 16px;
+  }
+
+  .status-row {
+    align-items: flex-start;
+    flex-direction: column;
+  }
+
+  .message {
+    text-align: left;
+  }
+
+  h1 {
+    font-size: 3rem;
+  }
+
+  .move-list {
+    max-height: 180px;
+  }
+}
+