$all-size: ();
$all-size: map-merge(
        (
            '32':32,
            '40':40,
            '50':50,
        ),
        $all-size
);

@each $name, $val in $all-size {
    .size-#{$name} {
        width: #{$val}px;
        min-width: #{$val}px;
        height: #{$val}px;
    }
}