frontend/src/components/Toast.jsx

import React from 'react';

// Toast — fixed bottom-center notification bar.
// Renders nothing when msg is null.
// App owns the toast state and the showToast helper (sets msg, clears after 2600ms).
export default function Toast({ msg }) {
  if (!msg) return null;
  return <div className="ap-toast">{msg}</div>;
}