diff --git a/AlgebraicDataflowArchitectureModel/src/simulator/interfaces/html/HtmlElement.java b/AlgebraicDataflowArchitectureModel/src/simulator/interfaces/html/HtmlElement.java
index 0373165..a1264f4 100644
--- a/AlgebraicDataflowArchitectureModel/src/simulator/interfaces/html/HtmlElement.java
+++ b/AlgebraicDataflowArchitectureModel/src/simulator/interfaces/html/HtmlElement.java
@@ -1,7 +1,9 @@
 package simulator.interfaces.html;
 
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Map;
+import java.util.Set;
 
 import models.algebra.Constant;
 import models.dataConstraintModel.JsonTerm;
@@ -13,6 +15,7 @@
 	private final String id;
 	private String text;
 	private Map<String, String> styles;
+	private Set<String> classes;
 	private IRestEventListener restEventListener;
 	
 	HtmlElement(String type, String id, String text){
@@ -20,6 +23,7 @@
 		this.id = id;
 		this.text = text;
 		styles = new HashMap<>();
+		classes = new HashSet<>();
 	}
 	
 	public void setStyle(String property, String value) {
@@ -30,6 +34,14 @@
 		styles.remove(property);
 	}
 	
+	public void addClass(String className) {
+		classes.add(className);
+	}
+	
+	public void removeClass(String className) {
+		classes.remove(className);
+	}
+	
 	public MapTerm toMap() {
 		MapTerm res = new MapTerm();
 		res.insert("\"type\"", new Constant("\"" + type + "\""));
@@ -40,6 +52,8 @@
 			stylesMap.insert(prop, new Constant(styles.get(prop)));
 		}
 		res.insert("\"styles\"", stylesMap);
+		String classTmp = String.join(" ", classes);
+		res.insert("\"class\"", new Constant(classTmp));
 		return res;
 	}