:root {
  color-scheme: light;
  font-family: system-ui, -apple-system, Segoe UI, sans-serif;
}

body {
  margin: 0;
  background: #f5f5f7;
  color: #1a1a1a;
}

main {
  max-width: 420px;
  margin: 48px auto;
  padding: 0 20px;
}

h1 {
  font-size: 1.4rem;
}

code {
  background: #e8e8ec;
  border-radius: 4px;
  padding: 1px 5px;
  font-size: 0.9em;
}

.card {
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 10px;
  padding: 20px;
  margin-top: 16px;
}

.hint {
  color: #666;
  font-size: 0.85rem;
}

.button {
  display: flex;
  align-items: center;
  width: 100%;
  background: #1a1a1a;
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 14px 16px;
  font-size: 1rem;
  cursor: pointer;
  text-decoration: none;
  margin-bottom: 10px;
  box-sizing: border-box;
}

.button:hover {
  filter: brightness(1.15);
}

.button--google {
  background: #4285f4;
}

.button--disabled {
  background: #ccc;
  color: #777;
  cursor: not-allowed;
}