body {
  font-family: Arial, sans-serif;
  margin: 20px;
}

button {
  margin: 5px;
  padding: 8px 12px;
  cursor: pointer;
}

.demo-block {
  margin-bottom: 40px;
  padding: 15px;
  border: 1px solid #ccc;
  border-radius: 8px;
}

#table-container table {
  border-collapse: collapse;
  width: 100%;
  margin-top: 10px;
}

#table-container th,
#table-container td {
  border: 1px solid black;
  padding: 8px;
  text-align: center;
}