css logical inset-block-start: Set fg & bg color

For the demonstration element with
background-color: yellow, also set explicit
foreground color. Prevents white-on-yellow
text, with the dark skin.

live-examples/css-examples/logical-properties/inset-block-start.css

@@ -9,6 +9,7 @@
 
 #abspos {
   background-color: yellow;
+  color: black;
   border: 3px solid red;
   position: absolute;
   inset-block-start: 50px;