2 different text sizes in the title field (Hero Block)

Hello,

I have some questions about the Hero Section Block, the block’s settings only allow one title field and one text field

I managed to make the title into 2 rows by using the <br> tag. However, I would also like to have one of the rows to have a different text size, but I could not make it because it is on the same field and the settings will apply to the whole field.

The link I sent is a screenshot and I have circled the text which I wish it can be bigger.

Note: <H1> tag does not work because it will enlarge all text on the field.

Thank you

The page I need help with: [log in to see the link]