making <pre> tags make code snippets show up in a browser nicely

I put this in my style.css file in this drupal installation:

code, tt, pre {
background-color: #EDF1F3;
font-family: "Bitstream Vera Sans Mono",Monaco,"Lucida Console",monospace;
font-size: 0.9em;
line-height: 1.2em;
}