Static polyfill for vw, vh, vm units

vunits.js

/**
 * Polyfill for the vw, vh, vm units including StyleFix
 * @author Lea Verou
 */
(function(){
  
  if(!window.addEventListener) {
  	return;
  }
  
  var self = window.StyleFix = {
  	link: function(link) {
  		try {
  			if(!/\bstylesheet\b/i.test(link.rel) || !link.sheet.cssRules) {
  				return;
  			}
  		}
  		catch(e) {
  			return;
  		}
  
  		var url = link.href || link.getAttribute('data-href'),
  		    base = url.replace(/[^\/]+$/, ''),
  		    parent = link.parentNode,
  		    xhr = new XMLHttpRequest();
  
  		xhr.open('GET', url);
  
  		xhr.onreadystatechange = function() {
  			if(xhr.readyState === 4) {
  				var css = xhr.responseText;
  
  				if(css && link.parentNode) {
  					css = self.fix(css, true, link);
  
  					// Convert relative URLs to absolute, if needed
  					if(base) {
  						css = css.replace(/url\((?:'|")?(.+?)(?:'|")?\)/gi, function($0, url) {
  							if(!/^([a-z]{3,10}:|\/)/i.test(url)) { // If url not absolute
  								// May contain sequences like /../ and /./ but those DO work
  								return 'url("' + base + url + '")';
  							}
  
  							return $0;						
  						});
  
  						// behavior URLs shoudn’t be converted (Issue #19)
  						css = css.replace(RegExp('\\b(behavior:\\s*?url\\(\'?"?)' + base, 'gi'), '$1');
  					}
  
  					var style = document.createElement('style');
  					style.textContent = css;
  					style.media = link.media;
  					style.disabled = link.disabled;
  					style.setAttribute('data-href', link.getAttribute('href'));
  
  					parent.insertBefore(style, link);
  					parent.removeChild(link);
  				}
  			}
  		};
  
  		xhr.send(null);
  
  		link.setAttribute('data-inprogress', '');
  	},
  
  	styleElement: function(style) {
  		var disabled = style.disabled;
  
  		style.textContent = self.fix(style.textContent, true, style);
  
  		style.disabled = disabled;
  	},
  
  	styleAttribute: function(element) {
  		var css = element.getAttribute('style');
  
  		css = self.fix(css, false, element);
  
  		element.setAttribute('style', css);
  	},
  
  	process: function() {
  		// Linked stylesheets
  		$('link[rel~="stylesheet"]:not([data-inprogress])').forEach(StyleFix.link);
  
  		// Inline stylesheets
  		$('style').forEach(StyleFix.styleElement);
  
  		// Inline styles
  		$('[style]').forEach(StyleFix.styleAttribute);
  	},
  
  	register: function(fixer, index) {
  		(self.fixers = self.fixers || [])
  			.splice(index === undefined? self.fixers.length : index, 0, fixer);
  	},
  
  	fix: function(css, raw) {
  		for(var i=0; i<self.fixers.length; i++) {
  			css = self.fixers[i](css, raw) || css;
  		}
  
  		return css;
  	},
  
  	camelCase: function(str) {
  		return str.replace(/-([a-z])/g, function($0, $1) { return $1.toUpperCase(); }).replace('-','');
  	},
  
  	deCamelCase: function(str) {
  		return str.replace(/[A-Z]/g, function($0) { return '-' + $0.toLowerCase() });
  	}
  };
  
  /**************************************
   * Process styles
   **************************************/
  (function(){
  	setTimeout(function(){
  		$('link[rel~="stylesheet"]').forEach(StyleFix.link);
  	}, 10);
  
  	document.addEventListener('DOMContentLoaded', StyleFix.process, false);
  })();
  
  function $(expr, con) {
  	return [].slice.call((con || document).querySelectorAll(expr));
  }
  
  
  // Feature test
  var dummy = document.createElement('_').style,
  	units = ['vw', 'vh', 'vm'].filter(function(unit) {
  		dummy.width = '';
  		dummy.width = '10' + unit;
  		return !dummy.width;
  	});
  
  if(!units.length) {
  	return;
  }
  
  StyleFix.register(function(css) {
  	var w = innerWidth, h = innerHeight, m = Math.min(w,h);
  	
  	return css.replace(RegExp('\\b(\\d+)(' + units.join('|') + ')\\b', 'gi'), function($0, num, unit) {
  		switch (unit) {
  			case 'vw':
  				return (num * w / 100) + 'px';
  			case 'vh':
  				return num * h / 100 + 'px';
  			case 'vm':
  				return num * m / 100 + 'px';
  		}
  	});
  });

})();

it's not working with window resize in safari browser.