Use SVG background images with automatic PNG fallback (LESS mixin)

svg-background-image.less

.svg-background-image(@svg,@fallback){
	/*
	From css-tricks.com/using-svg/
	coincidentally, if multiple backgrounds are supported, then so are SVG images!
		
	Usage:
	.svg-background-image('my.svg','fallback.png');
		
	*/
	background-image: url('@{fallback}');
	background-image: url('@{svg}'), none;
}