- shaded sounds: since using common flex-displayed div per two sounds,
idk how to show the impossible sound (gray-shaded cells).
Probably is better to utilize the grid variant, since the
gapdoesn't go finely as it depends on the widths of the string with the letters. If the sound cell has no letter, it has 0 width, so the non-empty cell sinks towards the neighboring empty cell. - add the dots in between the vowel pairs : https://upload.wikimedia.org/wikipedia/commons/8/8f/IPA_chart_2020.svg
