This is what I use for a Mixin with sass, it allows me to quickly reference the breakpoint that I want. obviously you can adjust the media query list to suite your project mobile fist etc.
But it will jin multiple queries for you as I believe you're asking for.  
$size__site_content_width: 1024px;
/* Media Queries */ Not necessarily correct, edit these at will 
$media_queries : (
    'mobile'    : "only screen and (max-width: 667px)",
    'tablet'    : "only screen and (min-width: 668px) and (max-width: $size__site_content_width)",
    'desktop'   : "only screen and (min-width: ($size__site_content_width + 1))",
    'retina2'   : "only screen and (-webkit-min-device-pixel-ratio: 2) and (min-resolution: 192dpi)",
    'retina3'   : "only screen and (-webkit-min-device-pixel-ratio: 3) and (min-resolution: 288dpi)",
    'landscape' : "screen and (orientation:landscape) ",    
    'portrait'  : "screen and (orientation:portrait) "
);
@mixin for_breakpoint($breakpoints) {
    $conditions : ();
    @each $breakpoint in $breakpoints {
        // If the key exists in the map
        $conditions: append(
            $conditions,
            #{inspect(map-get($media_queries, $breakpoint))},
            comma
        );
    }
    @media #{$conditions} {
        @content;
    }
}
Use it like this in your scss:
#masthead {
    background: white;
    border-bottom:1px solid #eee;
    height: 90px;
    padding: 0 20px;
    @include for_breakpoint(mobile desktop) {
        height:70px;
        position:fixed;
        width:100%;
        top:0;
    }
}
Then this will compile to:
#masthead { 
  background: white;
  border-bottom: 1px solid #eee;
  height: 90px;
  padding: 0 20px;
}
@media only screen and (max-width: 667px), only screen and (min-width: 1025px) {
  #masthead {
    height: 70px;
    position: fixed;
    width: 100%;
    top: 0;
  }
}