Large bold type should be used to establish a clear information hierarchy. These are the recommended 'Header' type sizes.
Georgia Italic should be used to denote a short quotation from BBC Blogs or third party websites. The recommended type sizes are: 16px in a pull-out box where there is one quotation (e.g. Quotation promo to BBC Blogs) and 14px in a module where there is more than one quotation (eg. Twitter feed module).
CSS offset for Arial: 0.5 x Line Height - 0.35 x Font size
CSS offset for Georgia: 0.5 x Line Height - 0.31 x Font size
*For more information visit: CSS Discrepancy