SASS Custom Mixins

_custom-mixins.scss

// Cross browser opacity
@mixin opacity ( $value: 0.5 ) {
	opacity: $value;
	-ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=" $value * 100 ")";
	filter: alpha(opacity= $value * 100 );
	zoom: 1;
}

// Media Queries
@mixin mq($query) {
	@media #{$query} { @content; };
}
@mixin mqmax($size) {
	@media only screen and (max-width: $size) { @content; }
}
@mixin mqmin($size) {
	@media only screen and (min-width: $size) { @content; }
}

// Absolutely position elements
@mixin abs ($top: false, $right: false, $bottom: false, $left: false) {
	position: absolute;
	@if $top { top: $top; }
	@if $right { right: $right; }
	@if $bottom { bottom: $bottom; }
	@if $left { left: $left; }
}

/**
 * Returns a list of all text-based input types (excluding textarea)
 * @pseudo {String} 	An optional pseudo selector (eg: :hover, :focus)
 * @additional {List} 	An optional list of additional input types posible types include: color, date, datetime, datetime-local, month, time, week
 */
$text-inputs: 	"text",
				"email",
				"url",
				"tel",
				"number",
				"search",
				"password";

@mixin textfields($pseudo: '', $additional: ()) {
	$types: ();
	@each $type in $text-inputs {
		$types: append($types, unquote('&[type="#{$type}"]#{$pseudo}'), comma);
	}	
	@each $type in $additional {
		$types: append($types, unquote('&[type="#{$type}"]#{$pseudo}'), comma);
	}
	input {
		#{$types} {
			@content
		}
	}
}