$unit: 4px;
$double: $unit * 2;
$half: $unit * 5;
$deca: $unit * 10;

%h1 {
  font-size: $deca;
  line-height: $deca;
  color: #cfcfcf;
}

%h2 {
  font-size: $double * 3;
  line-height: $double * 3;
}

%h3 {
  font-size: $deca / 2;
  line-height: $deca / 2;
}

%h4 {
  font-size: $double * 2;
  line-height: $double * 2;
}

%text {
  font-size: $double * 2;
  line-height: $double * 7/2;
}