How do we resize title headings

Hi, I like the impulse theme very much but the font size of the page title is rather dominant especially when used on a mobile device (the point of the responsive theme) please can you explain how to reduce the size. I can see that they are 44 pixels but can’t see where this is in the coding to change it to about 30 pixels. If I can’t resolve this I will need to look for a new theme. I do hope you can help. Many thanks.