Skip to content

Instantly share code, notes, and snippets.

@brianblakely

brianblakely/rem-calibrate.css

Created July 13, 2012 18:55
Show Gist options
  • Save brianblakely/3106678 to your computer and use it in GitHub Desktop.
Save brianblakely/3106678 to your computer and use it in GitHub Desktop.
Download ZIP
Simulate vw with rems
Raw
rem-calibrate.css
/* Android stock browser won't let you set font-size smaller than 8px unless you apply this. */
:root {
-webkit-text-size-adjust: none;
-moz-text-size-adjust: none;
-ms-text-size-adjust: none;
-o-text-size-adjust: none;
text-size-adjust: none;
}
Raw
rem-calibrate.js
/*
Place this within a <script> in your <head>, prior to your stylesheet
Then use rems instead of px globally - your site will scale 1:1 with viewport width
*/
function remCalibrate() {
document.documentElement.style.fontSize = window.innerWidth/100 + 'px';
}
remCalibrate();
window.addEventListener('resize', remCalibrate, false);
@nonnenmacher
Copy link

Its great, thanks !

however there is few problems with this technique :

  1. it could lead to very small or big fonts when screen size is getting smaller or larger, so we could make some min, max to this function

  2. it doesn't take into account the aspect ratio of the screen, on a lot of laptop, the users have a much wider screen than the window height, so this computation tend to deliver them a greater font, that it should.

I had to adapt it for a one-page size all project and come up with a naive implementation, that patch the size according to 4:3 aspect ratio to compensate and using a [8,24] clipping range.

so its something like :

 // clip to a decent range size to avoid, making endless size adjustments as screens being bigger and bigger
    var aspect_ratio =  (window.innerHeight/window.innerWidth)/0.75
    var vwh =  window.innerWidth/100
    var rem = Math.max(8,Math.min(24,vwh*aspect_ratio))

    document.documentElement.style.fontSize =  rem + 'px';

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment