If you open your browser's developer console while on this page, you'll notice a styled console statement.

It only takes one line of JavaScript to accomplish this:

  "%c💁🏻 Hello there!",
  "color: #8971d0; font-size: 14px; font-weight: 700; padding: 4px; border: 2px solid #8971d0;"

The first argument includes the text I want to style (preceded by the %c directive), and the second argument includes the actual styles. Note that the %c directive in the first argument is important, because it marks the beginning of the styled span of text.

If you want to read more about styling your console (including with console.error or console.info), check out Mozilla's console documentation.