Native Detection for FF Pre 3.5

firefox.js.coffee

if /Firefox[\/\s](\d+\.\d+)/.test(navigator.userAgent)
  ffversion = new Number(RegExp.$1)
  if ffversion < 3.5
    head = document.getElementsByTagName("head")[0]
    el = document.createElement("link")
    el.type = "text/css"
    el.rel = "stylesheet"
    el.href = "/assets/firefox.css"
    el.media = "screen"
    head.appendChild el

firefox.scss

@import 'partials/base';
@import "public/public_base"; 
@import "public/public_321_up"; 
@import "public/public_535_up"; 
@import "public/public_767_up"; 
@import "public/public_940_up"; 
@import 'flexslider';

body {
  .container {
    width: 950px;
  }
}