Hope you’re well today and sorry about the delay here.
If you change the blog titles font size or style, it should fine and will not affect to the code structure.
I found more HTML element. It has a start tag and end tag
If you’re need to modifying a theme, then we recommend using a child theme and the changes will not be overwritten when the theme is updated. more about child theme: http://codex.wordpress.org/Child_Themes
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