Fixed null pointer possibility in CssParser

src/dorkbox/systemTray/util/CssParser.java

@@ -403,6 +403,7 @@ class CssParser {
 
         // get the attribute from the highest scoring node
         //noinspection ConstantConditions
+        if (maxNode != null) {
             for (CssAttribute attribute : maxNode.attributes) {
                 if (equalsOrContained) {
                     if (attribute.key.equals(attributeName)) {
@@ -415,6 +416,7 @@ class CssParser {
                     }
                 }
             }
+        }
 
         return null;
     }