diff --git a/README.md b/README.md
index e0785ce52ee387c076f9c78da658bc6e9a96282c..6ff3644babaa1525c9c8eb6e1be4b4cc07c3bea3 100644
--- a/README.md
+++ b/README.md
@@ -10,18 +10,25 @@ Copyright © 2023 Germann, Nakielski, Dietsch, Petzel, Moser, Triesch, Westhoff
 ``` mermaid
 flowchart LR
     p(publication)-->s1(Englund-2014) 
-    p-->s2(Synechocystis) -->a1(AbsorptionSpectraAndODMeasurements) & a2(DCWMeasurement) & a3(PigmentQuantification) & a4(qPCR) 
+    
+subgraph with a title
+p-->s2(Synechocystis) -->a1(AbsorptionSpectraAndODMeasurements) & a2(DCWMeasurement) & a3(PigmentQuantification) & a4(qPCR) 
+end
+
+subgraph assays
     p-->s3(PlasmidAndStrainConstruction)-->a5(MetabolicModeling)
+    subgraph nested
     p-->s4(MeasurementsOfSqualeneProduction)-->a6(GS-MSMeasurementsForTheQuantificationOfSqualene)
-    style s1 fill:#58D68D,stroke:#010802,color:#010802
-    style s2 fill:#58D68D,stroke:#010802,color:#010802
-    style s3 fill:#58D68D,stroke:#010802,color:#010802
-    style s4 fill:#58D68D,stroke:#010802,color:#010802
-    style p fill:#E9544A,stroke:#010802,color:#010802
-    style a1 fill:#F4D03F,stroke:#010802,color:#010802
-    style a2 fill:#F4D03F,stroke:#010802,color:#010802
-    style a3 fill:#F4D03F,stroke:#010802,color:#010802
-    style a4 fill:#F4D03F,stroke:#010802,color:#010802
-    style a5 fill:#F4D03F,stroke:#010802,color:#010802
-    style a6 fill:#F4D03F,stroke:#010802,color:#010802
+    end
+end
+
+%%Define styles
+    classDef study fill:#58D68D,stroke:#010802,color:#010802;
+    classDef publication fill:#E9544A,stroke:#010802,color:#010802;
+    classDef assay fill:#F4D03F,stroke:#010802,color:#010802;
+%%Assign styles
+class s1,s2,s3,s4 study;
+class p publication;
+class a1,a2,a3,a4,a5,a6 assay;    
+
 ```
\ No newline at end of file