body { font: 15px/1.5 -apple-system, system-ui, sans-serif; max-width: 32rem; margin: 3rem auto; padding: 0 1rem; color: #1a1a1a; }
  h1 { font-size: 1.25rem; }
  label { display: block; margin: 1rem 0 0.25rem; font-weight: 600; }
  input[type=text], input[type=email] { width: 100%; padding: 0.5rem; font-size: 1rem; box-sizing: border-box; }
  button { margin-top: 1.25rem; padding: 0.6rem 1.2rem; font-size: 1rem; cursor: pointer; }
  .msg { margin-top: 1.25rem; padding: 0.75rem; border-radius: 4px; }
  .msg.ok { background: #e6f4ea; color: #1e4620; }
  .msg.err { background: #fce8e6; color: #5f2120; }
  [hidden] { display: none !important; }