body {
  margin: 0;
  padding: 0;
  background-color: #eaf4ff;
  font-family: "Segoe UI", "Yu Gothic UI", sans-serif;
  text-align: center;
}

.container {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 32px 16px;
  max-width: 360px;
  margin: 0 auto;
}
#lineLogin {
  padding: 14px 20px;
  background-color: #00c300;
  color: white;
  border: none;
  border-radius: 16px;
  font-size: 18px;
  font-weight: bold;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 90%;
  max-width: 280px;
  margin: 16px auto;
  touch-action: manipulation;
  box-sizing: border-box;
}
/* ボタン共通スタイル */
a.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4em;
  background-color: #007bff;
  color: white;
  text-decoration: none;
  padding: 14px 20px;
  margin: 8px 0;
  border-radius: 16px;
  font-size: 1rem;
  font-weight: bold;
  width: 100%;
  max-width: 280px;
  box-sizing: border-box;
  transition: background-color 0.2s ease;
}

a.button:hover {
  background-color: #005fcc;
}

/* 緑ボタン（夏休み宿題） */
a.button.green {
  background-color: #00bfa5;
}
a.button.green:hover {
  background-color: #009e87;
}

/* LINEログインボタン */
a.button.line {
  background-color: #00c300;
}
a.button.line:hover {
  background-color: #009e00;
}

/* アイコン調整 */
a.button .icon {
  font-size: 1.2em;
}
a.button2 {
  position: fixed;
  left: 12px;
  bottom: 12px;
  background-color: #e0e0e0;
  color: #333;
  font-size: 0.75rem;
  padding: 6px 10px;
  border-radius: 6px;
  text-decoration: none;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.1);
  z-index: 1000;
  transition: background-color 0.2s ease;
}

a.button2:hover {
  background-color: #d5d5d5;
}
.footer-zone {
  background-color: #f0f0f0;
  padding: 12px 16px;
  text-align: center;
  font-size: 0.85rem;
  color: #555;
  border-top: 1px solid #ccc;
}

.footer-zone a {
  margin: 0 8px;
  text-decoration: none;
  color: #007bff;
  font-weight: bold;
}

.footer-zone a:hover {
  text-decoration: underline;
}