Update ui.py

ui.py

@@ -405,9 +405,10 @@ def render_multifile_summary(plotly_config=None):
             # Build consistent color maps using the same _PALETTE as per-file charts
             # Voice category colors — always fixed
             voice_color_map = {
-                "Single Voice": utils._PALETTE[0],   # red shade 0
-                "Multi Voice":  utils._PALETTE[9],   # green shade 0
-                "No Voice":     utils._PALETTE[-1],  # grey
+                "Single Voice": utils._PALETTE[0],    # reserved
+                "Multi Voice":  utils._PALETTE[9],    # reserved
+                "No Voice":     utils._PALETTE[24],   # reserved
+                "Unassigned":   utils._PALETTE[31] if len(utils._PALETTE) > 31 else "#777a7d",
             }
             # Role/speaker colors — cycle through _SPEAKER_PALETTE by position
             role_color_map = {