Image rendering mixins

_image-rendering.sass

// Sharpen an image if it has become blurry due to upscaling or downscaling
// https://developer.mozilla.org/en/CSS/image-rendering
@mixin sharpen-image
	image-rendering:-moz-crisp-edges

// When photos are upscaled or downscaled, they often get blurry. Don't use
// this on flat color images, they will still appear blurry.
// https://developer.mozilla.org/en/CSS/image-rendering
@mixin high-quality-image
	image-rendering:optimizeQuality

// Optimizes the rendering on images so they
// appear faster, but at a lower quality. Useful for <video>
@mixin low-quality-image
	image-rendering:optimizeSpeed