Change sentiment heatmap from stacked bar to multi-line chart

frontend/streamlit_app.py

@@ -1453,17 +1453,17 @@ if not heatmap_data.empty:
 
     fig_heat = go.Figure()
     for sent, color in [("Positive", "#22c55e"), ("Neutral", "#eab308"), ("Negative", "#ef4444")]:
-        fig_heat.add_trace(go.Bar(
+        fig_heat.add_trace(go.Scatter(
             x=heatmap_data["bucket"],
             y=heatmap_data[sent],
             name=sent,
-            marker_color=color,
-            opacity=0.85,
+            mode="lines+markers",
+            line=dict(color=color, width=2),
+            marker=dict(size=4),
             hovertemplate=f"<b>{sent}</b><br>%{{x}}<br>Count: %{{y}}<extra></extra>",
         ))
 
     layout = plotly_layout(220)
-    layout["barmode"] = "stack"
     layout["showlegend"] = True
     layout["legend"] = dict(orientation="h", y=1.08, font=dict(size=11))
     layout["xaxis"]["tickformat"] = "%H:%M"

pages/stats.py

@@ -340,17 +340,19 @@ if not heatmap_data.empty:
 
     fig_heat = go.Figure()
     for sent, color in [("Positive", "#22c55e"), ("Neutral", "#eab308"), ("Negative", "#ef4444")]:
-        fig_heat.add_trace(go.Bar(
+        fig_heat.add_trace(go.Scatter(
             x=heatmap_data["bucket"],
             y=heatmap_data[sent],
             name=sent,
-            marker_color=color,
-            opacity=0.85,
+            mode="lines+markers",
+            line=dict(color=color, width=2),
+            marker=dict(size=4),
+            fill="tozeroy" if sent == "Negative" else None,
+            fillcolor=color.replace(")", ",0.08)").replace("rgb", "rgba") if sent == "Negative" else None,
             hovertemplate=f"<b>{sent}</b><br>%{{x}}<br>Count: %{{y}}<extra></extra>",
         ))
 
     layout = plotly_layout(220)
-    layout["barmode"] = "stack"
     layout["showlegend"] = True
     layout["legend"] = dict(orientation="h", y=1.08, font=dict(size=11))
     layout["xaxis"]["tickformat"] = "%H:%M"