+/* foreground representation */
+#digraphs .u-l3 {color: #080} /* partial */
+#digraphs .u-l3.ex {color: #4C0} /* experimental */
+#digraphs .u-l2 {color: #A44; color: rgba(128, 0, 0, .6)} /* unofficial proposal */
+#digraphs .u-l1 {color: #D00; color: rgba(255, 0, 0, .8)} /* minimal or invalid */
+
+/* support percentage (browser cells) */
+.p0 {opacity: .6}