Increase font size of number of items in bag

Can anyone help me with increasing the font size for the number of items in the shopping cart in the header please.

If anyone knows how to add a a background colour behind the number of items in the cart that would be super helpful, if its possible.

Many thanks

You can try: 

1.5em just means 1.5x its current size. 

<script> 
  .icon-cart-quantity .sqs-cart-quantity { 
    font-size: 1.5em; 
  }
</script> 

Your a star.  Thanks