ZURB Foundation px Fallback for rem

_rem-fallback.scss

// Foundation settings example
$base-font-size: 62.5%;
$rem-base: 10px;

// Mixin using rem-calc from ZURB Foundation, but adding pixel fallback
@mixin rem-fallback($property, $values, $base-value: $rem-base){
    #{$property}: $values;
    #{$property}: rem-calc($values, $base-value: $rem-base);
}

// Example
html {
    font-size: $base-font-size;
}

body {
    font-family: 'Helvetica Neue', 'Open Sans', Helvetica, sans-serif;
    @include rem-fallback(font-size, 16px);
}

// Output
html {
    font-size: 62.5%;
}

body {
    font-family: 'Helvetica Neue', 'Open Sans', Helvetica, sans-serif;
    font-size: 16px;
    font-size: 1.6rem;
}

To use the rem-fallback with just an integer-variable as parameter the line 7 should be changed to the following:
#{$property}: #{$values}px;