-td.Co {background: #A99} /* private */
-
-/* implementation-based alternatives */
-td.di-b {background: #FDD} /* bmp */
-td.di-d {background: #FFD} /* rfc-1345 digraph */
-td.di-prop {background: #FED} /* proposed digraph */
-td.di-a {background: #EFD} /* ascii */
-td.di-rare {background: #EEE} /* disfavoured */
-td.di-invalid {background: #BBB} /* impossible */
+td.Co {background: #DCC} /* private */
+td.Xi, td.Cs {background: #CCC} /* invalid */
+td.Xd {color: #844} /* deprecated */
+td.Xr {color: #888} /* reserved (digraph reverse or proposal) */
+.dimap td.Xr {background: #EEE} /* reversed digraph */
+.ccmap td.Xr {opacity:.4}
+
+/* support levels */
+td.l0 {background: #FDD} /* no, unsupported, other */
+td.l2 {background: #FED} /* partial, restricted, unofficial */
+ /* default u-prop, u-bmp */
+td.l4 {background: #FFD} /* almost, imperfect, common */
+ /* default u-di, u-lat1 */
+td.l5 {background: #EFD} /* yes, supported, ubiquitous, native */
+ /* default u-ascii */
+td.l6 {background: #DFD} /* complete, perfect */
+td.ex {background: #EEE} /* experimental, disfavoured */
+td.u-invalid {background: #BBB} /* invalid, impossible */
+
+/* code syntax */
+.sy-comment { color: #888 }
+.sy-constant { color: #008 }
+.sy-type,
+.sy-identifier { color: #804 }
+.sy-statement { }
+.sy-preProc { }
+.sy-special { color: #408 }
+.sy-error { font-weight: bold; background-color: #F00; color: #FFF }
+.sy-todo { background-color: #FF0 }