body {
  font-family: system-ui, -apple-system, Segoe UI, sans-serif;
  background: #f5f7fa;
  color: #111827;
}

.container {
  max-width: 900px;
  margin: 40px auto;
  background: #ffffff;
  padding: 40px;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.08);
}

h1 { margin-top: 0; }

.intro { color: #4b5563; }

.question { margin-bottom: 24px; }

.question p { font-weight: 600; }

label { margin-right: 16px; }

.btn-primary {
  background: #2563eb;
  color: white;
  border: none;
  padding: 14px 22px;
  font-weight: 600;
  border-radius: 8px;
  cursor: pointer;
}

.btn-secondary {
  display: inline-block;
  margin-top: 20px;
  background: #111827;
  color: white;
  padding: 14px 22px;
  border-radius: 8px;
  font-weight: 600;
  text-decoration: none;
}

.result {
  margin-top: 30px;
  padding: 24px;
  background: #f0f9ff;
  border-radius: 8px;
}

.hidden { display: none; }