Increasing the font size for just certain cells/one notebook in Jupyter notebook

I want to increase the font size and add boldness to my outputted text in Jupyter notebook. However, I just want to change the settings for that particular notebook or that particular cell. (both solutions are welcomed)

I see most threads showing how to configure the .css files which I'm assuming is a global change?

How to change font in ipython notebook

However I want cell by cell control or just that particular notebook.

As an example output of one my cells is the following:

Killing C.I.A. Informants, China Crippled U.S. Spying https://www.nytimes.com/2017/05/20/world/asia/china-cia-spies-espionage.html

I would like to make the first sentence(the title) bold.

Thank you.

EDIT: Trying to utilize the markdown method within this loop.

for i in today_links:
    if i[0] == '':
        del (i)
    else:
        Markdown('**{}**  \n{}'.format(i[0], i[1]))

today_links is a list of tuples

[('Killing C.I.A. Informants, China Crippled U.S. Spying',
  'https://www.nytimes.com/2017/05/20/world/asia/china-cia-spies-espionage.html'),
 ('How Rollbacks at Pruitt’s E.P.A. Are a Boon to Oil and Gas',
  'https://www.nytimes.com/2017/05/20/business/energy-environment/devon-energy.html'),

Not sure why it's not working within the loop.

Thank you.