* {
  box-sizing: border-box;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

body {
  background-color: #f9f9f9;
  margin: 0;
  padding: 0;
  display: flex;
  height: 100vh;
  justify-content: center;
  align-items: center;
}

main {
  background: white;
  padding: 2rem 3rem;
  border-radius: 20px;
  box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
  text-align: center;
}

h1 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  font-weight: 600;
  color: #1d1d1f;
}

.code-input {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.code-input input {
  width: 3rem;
  height: 3rem;
  font-size: 1.5rem;
  text-align: center;
  border: 1px solid #ccc;
  border-radius: 8px;
}

button {
  background-color: #0071e3;
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  border-radius: 12px;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

button:hover {
  background-color: #005bb5;
}

#result {
  margin-top: 1.5rem;
  font-weight: 500;
  color: #333;
}