<Grid>
    <Column md={4} lg={7} sm={4}>
      7/16
    </Column>
    <Column md={4} lg={{ span: 8, offset: 8 }} sm={4}>
      8/16
    </Column>
  </Grid>

const processDataCols = () => {
  const dataCols = document.querySelectorAll(['data-cols']);
  
  /* for each data col split out sizes, spans and starts then apply Carbon column classes */

  [...dataCols].forEach((dataColEl) => {
    const attr = dataColEl.getAttribute('data-cols');
    const colSizes = attr.split(',');
    colSizes.forEach((colSize) => {
      const [size, value] = colSize.split(' ');
      const parts = value.split['s'];
      const span = parts.pop();
      if (parts.length > 0) {
        const start = parts.pop();
        dataColEl.classList.add(`cds--${size}:col-start-${start}`);
      }
      dataColEl.classList.add(`cds--${size}:col-span-${span}`);
    });
  });
}