migration to altair plots

theme.py

@@ -23,3 +23,58 @@ class ColorPalette:
     TEXT = "black"
     GRID = "lightgray"
     BACKGROUND = "white"
+
+
+def jpmc_altair_theme():
+    """JPMC brand theme for Altair charts."""
+    return {
+        'config': {
+            'view': {
+                'continuousWidth': 1000,
+                'continuousHeight': 500,
+                'strokeWidth': 0
+            },
+            'background': ColorPalette.BACKGROUND,
+            'axis': {
+                'grid': True,
+                'gridColor': ColorPalette.GRID,
+                'labelFontSize': 11,
+                'titleFontSize': 12,
+                'labelColor': ColorPalette.TEXT,
+                'titleColor': ColorPalette.TEXT,
+                'labelLimit': 200  # Allow longer labels before truncation
+            },
+            'axisX': {
+                'labelAngle': -45,
+                'labelLimit': 200  # Allow longer x-axis labels
+            },
+            'axisY': {
+                'labelAngle': 0
+            },
+            'legend': {
+                'orient': 'top',
+                'direction': 'horizontal',
+                'titleFontSize': 11,
+                'labelFontSize': 11
+            },
+            'title': {
+                'fontSize': 14,
+                'color': ColorPalette.TEXT,
+                'anchor': 'start',
+                'subtitleFontSize': 10,
+                'subtitleColor': 'gray'
+            },
+            'bar': {
+                'color': ColorPalette.PRIMARY
+            }
+        }
+    }
+
+
+# Register Altair theme
+try:
+    import altair as alt
+    alt.themes.register('jpmc', jpmc_altair_theme)
+    alt.themes.enable('jpmc')
+except ImportError:
+    pass  # Altair not installed