def format_card(note: str) -> str:
    """Formats a single org-mode note as an HTML card."""
    lines = note.split('\n')
    if lines[0].startswith('* '):
        card_front = '<br />{}<br />'.format(lines[0][2:])
    else:
        print('Received an incorrectly formatted note: {}'.format(note))
        return ''
    card_back = '<br />'.join(lines[1:])
    return card_front + '\t' + card_back