/* Phones: keep the page still. iOS Safari zooms into any focused field under 16px and does not zoom back. */
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}
/* Nothing may widen the page: a stray wide element would let the whole screen slide sideways.
   clip (not hidden) keeps the sticky header working. */
html,body{overflow-x:clip;overscroll-behavior-x:none}
body{max-width:100%}
img,video,canvas,iframe{max-width:100%}
/* No double-tap zoom on controls: fast taps in exercises must not magnify the page. */
a,button,input,select,textarea,label,summary,[role=button],[data-action],[data-cw]{touch-action:manipulation}
@media (pointer:coarse){
input:not([type=radio]):not([type=checkbox]):not([type=range]):not([type=file]):not([type=color]),textarea,select,[contenteditable=true]{font-size:max(16px,1em)!important}
}
/* No visible scrollbars anywhere, including the page itself; wheel, keyboard and touch scrolling still work. */
html,body,body *{scrollbar-width:none!important}
html::-webkit-scrollbar,body::-webkit-scrollbar,body *::-webkit-scrollbar{display:none!important;width:0!important;height:0!important}