body {
  font-family: Arial, sans-serif;
  background: #f5f7fb;
}

.container {
  max-width: 420px;
  margin: 50px auto;
}

.card {
  background: white;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

input, select, button {
  width: 100%;
  margin: 8px 0;
  padding: 10px;
}

button {
  background: #007bff;
  color: white;
  border: none;
  cursor: pointer;
}

.result {
  margin-top: 20px;
  font-size: 18px;
}