Add dark theme to Plotly charts only (preserves plotting functionality)

app.py

@@ -353,13 +353,13 @@ def create_interface():
                 return None, None, None
             
             fig_ms = px.line(df, x="Quarter", y=["Player Market Share", "AI Market Share"], title="Market Share (%)", markers=True, color_discrete_map={"Player Market Share": "#3b82f6", "AI Market Share": "#ef4444"})
-            fig_ms.update_layout(yaxis_range=[0,100], legend_title_text='')
+            fig_ms.update_layout(yaxis_range=[0,100], legend_title_text='', template="plotly_dark")
 
             fig_b = px.line(df, x="Quarter", y=["Player Budget", "AI Budget"], title="Budget ($)", markers=True, color_discrete_map={"Player Budget": "#3b82f6", "AI Budget": "#ef4444"})
-            fig_b.update_layout(legend_title_text='')
+            fig_b.update_layout(legend_title_text='', template="plotly_dark")
 
             fig_q = px.line(df, x="Quarter", y=["Player Product Quality", "AI Product Quality"], title="Product Quality Index", markers=True, color_discrete_map={"Player Product Quality": "#3b82f6", "AI Product Quality": "#ef4444"})
-            fig_q.update_layout(legend_title_text='')
+            fig_q.update_layout(legend_title_text='', template="plotly_dark")
 
             return fig_ms, fig_b, fig_q