Change default priority to low, add crayons, general refactoring

build/style.css

@@ -122,3 +122,11 @@ span.cardname {
   font-family: monospace;
   white-space: nowrap;
 }
+
+img.crayon {
+  vertical-align: middle;
+}
+
+table.level {
+  display: inline-block;
+}