Update README.md

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README.md

@@ -124,7 +124,17 @@ ABI is a combination of open source tools and proprietary technology. ABI relies
 We’re building the features of ChatGPT and its GPT Store with **Naas Workspace** and a power orchestration layer with **Naas API** using enterprise-grade, open source technologies.
 
 ```mermaid
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+%%{init: {
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+    'primaryTextColor': '#000',
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+    'lineColor': '#000',
+    'secondaryColor': '#f4f4f4',
+    'tertiaryColor': '#fff'
+  }
+}}%%
 flowchart LR
   user[End User]