.water-intake-calculator {
  font-family: Arial, sans-serif;
  max-width: 400px;
  margin: 0 auto;
  padding: 20px;
  background-color: #f4f4f4;
  border-radius: 8px;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.water-intake-calculator h2 {
  text-align: center;
  color: #333;
  font-size: 1.8em;
  margin-bottom: 20px;
}

label {
  display: block;
  margin-bottom: 8px;
  color: #333;
  font-size: 1em;
}

input, select {
  width: 100%;
  padding: 10px;
  margin-bottom: 15px;
  border: 1px solid #ddd;
  border-radius: 5px;
  font-size: 1em;
  box-sizing: border-box;
}

button {
  background-color: #5f9ea0;
  color: white;
  font-size: 1.1em;
  border: none;
  border-radius: 5px;
  padding: 12px;
  width: 100%;
  cursor: pointer;
  transition: background-color 0.3s ease;
}

button:hover {
  background-color: #4a8080;
}

.result-message {
  margin-top: 20px;
  font-size: 1.2em;
  font-weight: bold;
  color: #333;
  text-align: center;
}