<!DOCTYPE html>
<style>
    #first::before, #first::after { content: 'FAIL'; background: white; }
    #second::before, #second::after { content: 'FAIL'; background: navy; }
</style>
<p>There should be a blue block below:
<p><span id="first" style="color:white"></span> <span id="second" style="color:navy"></span>