How to highlight author comments in Blogger:
Step 1. Go to Template, click on Edit HTMLStep 2. Click anywhere inside the code area and try to find - using CTRL + F keys - this tag:
Just above it, paste the following code:
The line marked in orange represents the border's style.
What it can be done:
The line marked in blue represents the background's style. You can use a plain color or an image. By default there's a combination of both (a white transparent image with a gray plain color).
To change/add:
To change the font's color, replace the #444444 color value in green with your own. (you can use this tool to find the hex code of your desired color)
Font Size:
Modify the value in red by increasing/decreasing the "12" value in order to change the size of text.
Step 4. Now Save your Template.
To customize the entire style of threaded comments, please check my previous tutorial on How to Customize Comment's Background, Font Color and Border in Blogger.