/* ========================================================================== rtl.css — what changes when the lab reads right to left -------------------------------------------------------------------------- Linked from the of every page, and every rule in it is scoped to html[dir="rtl"], so on an English page it declares nothing at all. It was injected by lang.js at first, only when Arabic was on, which is cheaper and was wrong: an injected stylesheet can arrive after the first paint, and tests/uat-rtl.js caught five pages showing a frame of Latin tracking pulling Arabic words apart at the joins before this file landed. A stylesheet in the markup cannot lose that race. An English reader pays one small file that does nothing; an Arabic reader never sees a wrong frame. That is the trade and it is not close. THIS FILE IS THE SMALL HALF OF THE WORK. The large half was done in the stylesheets themselves, by replacing the properties that name a physical side with the ones that name a logical one: margin-left -> margin-inline-start padding-left -> padding-inline-start border-left -> border-inline-start text-align:left -> text-align:start left:0 -> inset-inline-start:0 Those render identically in English, byte for byte on screen, and they answer dir on their own. So they are not in here. What is in here is only the things a logical property cannot say. WHY THE LETTER-SPACING RULE CARRIES !important, and it is the only place in this lab that does. Arabic is a joined script. Tracking pulls the letters of a word apart at the joins, and the result is not "airy", it is misspelled-looking, the way s p a c e d Latin is merely airy but spaced Devanagari is broken. This lab declares letter-spacing in about a hundred and thirty places, most of them inside a