gistfile1.txt

function wpex_minify_css( $css ) {

	// Normalize whitespace
	$css = preg_replace( '/\s+/', ' ', $css );

	// Remove ; before }
	$css = preg_replace( '/;(?=\s*})/', '', $css );

	// Remove space after , : ; { } */ >
	$css = preg_replace( '/(,|:|;|\{|}|\*\/|>) /', '$1', $css );

	// Remove space before , ; { }
	$css = preg_replace( '/ (,|;|\{|})/', '$1', $css );

	// Strips leading 0 on decimal values (converts 0.5px into .5px)
	$css = preg_replace( '/(:| )0\.([0-9]+)(%|em|ex|px|in|cm|mm|pt|pc)/i', '${1}.${2}${3}', $css );

	// Strips units if value is 0 (converts 0px to 0)
	$css = preg_replace( '/(:| )(\.?)0(%|em|ex|px|in|cm|mm|pt|pc)/i', '${1}0', $css );

	// Return minified CSS
	return trim( $css );

}