dark-mode: invert the images in the About section

These images simply have too-dark labels otherwise.

The proper solution would likely involve a separate set of images in
that section, specifically targeting dark mode, with a
specially-designed color palette. But I am not the person you want to do
that, there are experts for this kind of stuff out there in the world, I
ain't one of them.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

assets/sass/dark-mode.css

@@ -72,6 +72,12 @@
             img {
                 filter: brightness(.6) contrast(1.2);
             }
+            // the images in the About section would be too dark
+            body#about img {
+                // filter: brightness(4) contrast(0.2);
+		filter: brightness(0.9) contrast(0.6) invert(1);
+            }
+
             // let the logo shine slightly brighter
             img[alt="Git"] {
                 filter: brightness(0.9) contrast(1.5);