body {
  font-family: Arial, sans-serif;
  background: #f9f9f9;
  margin: 0;
}

.container {
  max-width: 800px;
  margin: 40px auto;
  background: #fff;
  padding: 30px;
  border-radius: 10px;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
}

h2 {
  text-align: center;
  color: #2a3f54;
  margin-bottom: 10px;
}

p.subtitle {
  text-align: center;
  font-size: 16px;
  color: #555;
  margin-bottom: 25px;
}

label {
  font-weight: bold;
  margin-top: 15px;
  display: block;
  color: #444;
}

input {
  width: 100%;
  padding: 12px;
  border-radius: 8px;
  border: 1px solid #ccc;
  font-size: 16px;
  margin-top: 8px;
}

button {
  width: 100%;
  margin-top: 25px;
  padding: 14px;
  color: #fff;
  background: #2a3f54;
  border: none;
  font-size: 18px;
  cursor: pointer;
  border-radius: 8px;
}

button:hover {
  background: #1f2d3f;
}

.result-box {
  margin-top: 25px;
  padding: 20px;
  background: #eef4fa;
  border-radius: 8px;
  display: none;
}

.result-number {
  font-size: 32px;
  color: #2a3f54;
  font-weight: bold;
  text-align: center;
  margin-bottom: 6px;
}

.result-text {
  text-align: center;
  font-size: 18px;
  color: #333;
  padding-top: 6px;
}