* { box-sizing: border-box; }
body { font-family: system-ui, sans-serif; margin: 0; padding: 16px; max-width: 720px; margin-inline: auto; }
button { min-height: 44px; padding: 10px 16px; border-radius: 6px; border: 1px solid #888; background: white; cursor: pointer; }
button.primary { background: #1976d2; color: white; border-color: #1976d2; }
input { min-height: 44px; padding: 8px; border: 1px solid #aaa; border-radius: 6px; width: 100%; font-size: 16px; }
.row { display: flex; gap: 8px; align-items: center; margin-bottom: 12px; }
.error { color: #c00; }