body {
  font-family: 'Segoe UI', sans-serif;
  background: linear-gradient(to right, #d4fc79, #96e6a1);
  margin: 0;
  padding: 20px;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.calculator {
  background: #fff;
  padding: 30px;
  border-radius: 15px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
  width: 100%;
  max-width: 400px;
}

h2 {
  margin-bottom: 25px;
  text-align: center;
  color: #333;
}

label {
  font-weight: bold;
  margin-top: 20px;
  display: block;
  color: #444;
}

input[type=range] {
  width: 100%;
  margin-top: 8px;
}

input[type=number] {
  width: 100%;
  padding: 10px;
  margin-top: 8px;
  border: 1px solid #ccc;
  border-radius: 10px;
  font-size: 16px;
}

.result {
  background: #f0fff0;
  padding: 15px;
  border-radius: 10px;
  margin-top: 25px;
  text-align: center;
  border: 1px solid #c1eec1;
}

.result h3 {
  margin: 10px 0 0;
  font-size: 24px;
  color: #2b8a3e;
}

button {
  margin-top: 25px;
  width: 100%;
  padding: 15px;
  font-size: 16px;
  background: #4CAF50;
  color: white;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  transition: background 0.3s ease;
}

button:hover {
  background: #3b9440;
}