Inject CSS directly into HTML for older Gradio compatibility

app.py

@@ -686,8 +686,11 @@ except TypeError:
 
 with demo:
     
-    # Header with indigo gradient and glow effect
-    gr.HTML("""
+    # Inject CSS and Header with indigo gradient
+    gr.HTML(f"""
+        <style>
+        {custom_css}
+        </style>
         <div class="header-container">
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