Improve default rendering of header icon

Author: kzu

assets/css/style.scss

@@ -14,4 +14,13 @@ pre, code {
 
  code {
     font-size: 0.80em;
-}
+}
+
+h1 > img {
+    border: unset;
+    box-shadow: unset;
+    vertical-align: middle;
+    -moz-box-shadow: unset;
+    -o-box-shadow: unset;
+    -ms-box-shadow: unset;
+}