@mixin font-size($size)
  html
    font-size: $size;

@media (max-width: 480px)
  @include font-size(12px)

@media (min-width: 480px)
  @include font-size(13px)

@media (min-width: 786px)
  @include font-size(14px)

@media (min-width: 992px)
  @include font-size(15px)

@media (min-width: 1200px)
  @include font-size(16px)