The stretch
Arabic scribes justify a line by lengthening the connecting stroke between letters — the kashida — instead of widening the gaps between words. The text stays whole; one stroke absorbs the slack.
In CSS
A flex row with one flex: 1 child behaves the same way: everything keeps its size and a single element soaks up the space.
.row { display: flex; }
.row .kashida { flex: 1; }
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