:root { color-scheme: light dark; --accent: #3b6fd8; }
body { font: 17px/1.5 system-ui, -apple-system, sans-serif; margin: 0; display: grid;
  place-items: center; min-height: 100vh; padding: 0 16px; box-sizing: border-box; }
main { width: 100%; max-width: 360px; text-align: center; }
h1 { font-size: 1.6rem; margin-bottom: 0.25rem; }
p { margin: 0.5rem 0 1.25rem; opacity: 0.8; }
button { font: inherit; width: 100%; padding: 0.8rem 1rem; border: 0; border-radius: 12px;
  background: var(--accent); color: #fff; cursor: pointer; }
button.secondary { background: transparent; color: var(--accent); }
input { font: inherit; width: 100%; box-sizing: border-box; padding: 0.7rem 0.8rem;
  margin-bottom: 0.75rem; border-radius: 10px; border: 1px solid #8884; }
.error { color: #d33; min-height: 1.5em; }