* {
  box-sizing: border-box;
}

body {
  font-family: system-ui, -apple-system, sans-serif;
  margin: 0;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #f5f5f5;
}

.container {
  width: 100%;
  max-width: 420px;
  padding: 1rem;
}

.card {
  background: #fff;
  border-radius: 12px;
  padding: 1.5rem 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.card.hidden {
  display: none;
}

.card h1 {
  margin: 0 0 0.75rem;
  font-size: 1.25rem;
  font-weight: 600;
}

.card p {
  margin: 0 0 1rem;
  color: #555;
  font-size: 0.95rem;
}

.card p.message {
  color: #333;
}

.card code {
  background: #f0f0f0;
  padding: 0.15em 0.4em;
  border-radius: 4px;
  font-size: 0.9em;
  word-break: break-all;
}

.card.error {
  border-left: 4px solid #c00;
}

.card.error .message {
  color: #c00;
}

.btn {
  display: inline-block;
  padding: 0.6rem 1.2rem;
  background: #4285f4;
  color: #fff;
  text-decoration: none;
  border-radius: 8px;
  font-weight: 500;
  transition: background 0.2s;
}

.btn:hover {
  background: #3367d6;
}

.params {
  margin: 0;
}

.params dt {
  font-weight: 600;
  margin-top: 0.5rem;
  font-size: 0.85rem;
  color: #666;
}

.params dd {
  margin: 0.2rem 0 0;
  font-size: 0.9rem;
}

.params dd code {
  display: block;
  padding: 0.4rem;
  margin-top: 0.2rem;
}