Small CSS fix.

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@7276 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

stylesheets/lfs.css

@@ -265,6 +265,10 @@ tt, code, kbd, pre, .command {
   font-family: monospace;
 }
 
+tt.systemitem {
+  font-style: italic;
+}
+
 pre.userinput {
   color: #101310;
   background-color: #e5e5e5;