@function breakpoint-max($name, $breakpoints: $grid-breakpoints) {
    $next: breakpoint-next($name, $breakpoints);
    @return if($next, breakpoint-min($next, $breakpoints) - .02, null);
}

@function breakpoint-min($name, $breakpoints: $grid-breakpoints) {
    $min: map-get($breakpoints, $name);
    @return if($min != 0, $min, null);
}

// Makes the @content apply to the given breakpoint and wider.
@mixin media-breakpoint-up($name, $breakpoints: $grid-breakpoints) {
    $min: breakpoint-min($name, $breakpoints);
    @if $min {
        @media (min-width: $min) {
            @content;
        }
    } @else {
        @content;
    }
}

@function breakpoint-infix($name, $breakpoints: $grid-breakpoints) {
    @return if(breakpoint-min($name, $breakpoints) == null, "", "-#{$name}");
}

@function breakpoint-next($name, $breakpoints: $grid-breakpoints, $breakpoint-names: map-keys($breakpoints)) {
    $n: index($breakpoint-names, $name);
    @return if($n != null and $n < length($breakpoint-names), nth($breakpoint-names, $n + 1), null);
}

// Media of at most the maximum breakpoint width. No query for the largest breakpoint.
// Makes the @content apply to the given breakpoint and narrower.
@mixin media-breakpoint-down($name, $breakpoints: $grid-breakpoints) {
    $max: breakpoint-max($name, $breakpoints);
    @if $max {
        @media (max-width: $max) {
            @content;
        }
    } @else {
        @content;
    }
}