body {
  font-family: sans-serif;
  line-height: 1.6;
  margin: 20px;
  background-color: #f4f4f4;
}

h1,
h2 {
  color: #333;
  text-align: center;
}

.container {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  background-color: #fff;
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.form-section,
.preview-section {
  flex: 1;
  min-width: 300px;
}

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

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

.form-group input[type="number"],
.form-group input[type="text"] {
  width: calc(100% - 50px); /* Adjust width considering the span */
  padding: 8px;
  border: 1px solid #ccc;
  border-radius: 4px;
  box-sizing: border-box; /* Include padding and border in element's total width */
}
.form-group input[type="number"] {
  width: 60px; /* Shorter width for numbers */
}

.form-group span {
  font-size: 0.9em;
  color: #666;
  margin-left: 5px;
}

.button-group {
  margin-top: 20px;
  text-align: center;
}

button {
  padding: 10px 20px;
  background-color: #007bff;
  color: white;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  font-size: 1em;
  margin: 0 10px;
}

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

#previewArea {
  background-color: #e9e9e9;
  padding: 15px;
  border-radius: 5px;
  min-height: 150px;
  white-space: pre-wrap; /* Wrap long lines */
  word-wrap: break-word; /* Break words if needed */
  font-family: monospace;
  font-size: 0.9em;
  overflow-y: auto; /* Add scroll if content overflows */
  max-height: 400px; /* Limit height */
}

.reminder-group > div {
  margin-bottom: 5px; /* Thêm khoảng cách giữa checkbox và tùy chọn chi tiết */
}

#reminderOptions label,
#reminderOptions input,
#reminderOptions select {
  margin-right: 5px; /* Thêm khoảng cách nhỏ giữa các control */
}

textarea {
  width: 100%; /* Cho textarea rộng tối đa */
  padding: 8px;
  border: 1px solid #ccc;
  border-radius: 4px;
  box-sizing: border-box;
  font-family: sans-serif; /* Đảm bảo font giống các input khác */
  font-size: 1em;
}