CSS在pre元素中选择并设置粗体文本样式

I am reading the Java Tutorials Online, and sometimes you can find snippets of code declared with the pre tag. These snippets include plain text and some of it is in bold. I can't really differentiate normal text from bold text, so I'm using my browser's Stylish extension to create a CSS style that will modify the page's look and feel replacing the original. My goal is to change the color of the bold text inside the pre element to a color slightly different than black, like a very dark blue. What CSS selector can I use to select only bold text in a pre tag. Thanks!I am reading the Java Tutorials Online, and som