body {
  font-family: Arial, sans-serif;
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
  background-color: #f5f5f5;
}

.header {
  background-color: #2c5aa0;
  color: white;
  padding: 15px;
  border-radius: 5px;
  margin-bottom: 20px;
}

.container {
  background-color: white;
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  margin-bottom: 20px;
}

.login-form {
  max-width: 400px;
  margin: 0 auto;
}

.form-group {
  margin-bottom: 15px;
}

label {
  display: block;
  margin-bottom: 5px;
  font-weight: bold;
}

input[type="text"],
input[type="password"] {
  width: 100%;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 4px;
  box-sizing: border-box;
}

.btn {
  background-color: #2c5aa0;
  color: white;
  padding: 10px 20px;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  width: 100%;
}

.btn:hover {
  background-color: #1e3d6b;
}

.error-message {
  background-color: #f8d7da;
  color: #721c24;
  padding: 10px;
  border: 1px solid #f5c6cb;
  border-radius: 4px;
  margin: 15px 0;
}

.warning {
  background-color: #fff3cd;
  color: #856404;
  padding: 15px;
  border: 1px solid #ffeaa7;
  border-radius: 4px;
  margin: 20px 0;
}

.demo-links {
  background-color: #e7f3ff;
  padding: 15px;
  border-radius: 5px;
  margin-top: 20px;
}

.demo-links h3 {
  color: #1e3d6b;
  margin-top: 0;
}

.demo-links a {
  display: block;
  margin: 5px 0;
  color: #2c5aa0;
  text-decoration: underline;
}

.demo-links a:hover {
  background-color: #f0f8ff;
  padding: 5px;
  border-radius: 3px;
}

.back-link {
  display: inline-block;
  margin-top: 15px;
  color: #2c5aa0;
  text-decoration: none;
}

.back-link:hover {
  text-decoration: underline;
}

/* 管理者ダッシュボード用のスタイル */
.admin-dashboard {
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
  background-color: #fff;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.admin-menu {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin: 20px 0;
}

.admin-link {
  display: block;
  padding: 15px;
  background-color: #f8f9fa;
  color: #333;
  text-decoration: none;
  border-radius: 4px;
  text-align: center;
  transition: all 0.3s ease;
}

.admin-link:hover {
  background-color: #e9ecef;
  transform: translateY(-2px);
}

.admin-info {
  margin: 20px 0;
  padding: 15px;
  background-color: #f8f9fa;
  border-radius: 4px;
}

.admin-info pre {
  margin: 0;
  padding: 10px;
  background-color: #fff;
  border: 1px solid #dee2e6;
  border-radius: 4px;
  overflow-x: auto;
}

.btn-danger {
  background-color: #dc3545;
  color: #fff;
  border: none;
  padding: 10px 20px;
  border-radius: 4px;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

.btn-danger:hover {
  background-color: #c82333;
}