change image degredation algorithm

bin/degrade.sh

@@ -9,5 +9,5 @@ for f in *.jpg; do
 
     echo "Converting $f to gif"
 
-    convert "${f}" -verbose -format GIF -interlace GIF -resize 640\> -colorspace gray -colors 4 -ordered-dither h8x8a -transparent white -set filename:f "%[t]-degraded" "%[filename:f].gif"
+    convert "${f}" -verbose -format GIF -interlace GIF -resize 640\> -colorspace gray -colors 4 -ordered-dither h4x4a -set filename:f "%[t]-degraded" "%[filename:f].gif"
 done

http/_includes/head.html

@@ -93,7 +93,7 @@
         }
 
         .i {
-            background-color: #fff;
+            background-color: #aaa;
         }
 
         pre {