<!DOCTYPE html>
<html lang="ja">
<head>
<meta charset="UTF-8">
<title>3秒チャレンジゲーム</title>
</head>
<body>
<h1>3秒チャレンジゲーム</h1>
<button id="startButton">スタート</button>
<div id="gameArea"></div>
<div id="message"></div>
<script>
let countdown = 3;
let gameActive = false;
function startGame() {
document.getElementById("message").textContent = "";
countdown = 3;
gameActive = true;
}
function setupGameBoard() {
const gameArea = document.getElementById("gameArea");
gameArea.innerHTML = "";
for (let i = 1; i <= 10; i++) {
const box = document.createElement("div");
box.textContent = i;
gameArea.appendChild(box);
}
}
document.getElementById("startButton").addEventListener("click", startGame);
setupGameBoard();
</script>
</body>
</html>
