/* 全体を縦方向に構成 */
html, body {
  height: 100%;
  margin: 0;
  font-family: sans-serif;
  background-color: #f8f8f8;
  display: flex;
  flex-direction: column;
}

/* 中央コンテンツ部分 */
.container {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 2rem;
}

.content-box {
  text-align: center;
  padding: 2rem;
  background-color: white;
  border-radius: 1rem;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}


/* フッター */
footer {
  padding: 10px 20px;
  text-align: center;
  font-size: 0.7em;
  color: #999;
  line-height: 1.4;
  border-top: 1px solid #ddd;
  background-color: #f4f4f4;
  font-style: italic;
}


/* ボタン */
button {
  font-size: 1.2rem;
  padding: 0.8rem 1.5rem;
  border: none;
  border-radius: 0.5rem;
  background-color: #007bff;
  color: white;
  cursor: pointer;
}

button:hover {
  background-color: #0056b3;
}