$breakpoints: (
    // "phone": (0px,
    //     1400px),
    // "pc": 1400px,

);

@mixin responseTo($breakname) {
    $bp: map-get($breakpoints, $breakname);

    @if type-of($bp)=="list" {
        @media (min-width: nth($bp, 1)) and (max-width: nth($bp, 2)) {
            @content;
        }
    }

    @else {
        @media (min-width: $bp) {
            @content;
        }
    }
}