$size: (
  10: 10,
  12: 12,
  13: 13,
  14: 14,
  15: 15,
  16: 16,
  17: 17,
  18: 18,
  20: 20,
  22: 22,
  24: 24,
  26: 26,
  28: 28,
  30: 30,
  32: 32,
  34: 34,
  36: 36,
  38: 38,
  40: 40,
  42: 42,
  44: 44,
  46: 46,
  48: 48,
);

@each $item, $val in $size {
  .fs-#{$item} {
    font-size: #{$val}px !important;
  }
}