Refactor financial chart implementation

js/charts/ppmt_region_channel.js

@@ -1,5 +1,5 @@
 import {
-  PALETTE, FONT, titleStyle, footnote, watermarks,
+  PALETTE, FONT, titleStyle, footnote, watermarks, legendStyle,
 LAYOUT, } from '../theme.js';
 
 /**
@@ -44,7 +44,8 @@ export function regionChannelChart(rows, { width, height }) {
       top: 18,
     },
     legend: {
-      data: channels.map(name => ({ name, icon: 'rect' })),  // 全部堆叠柱状图
+      ...legendStyle,
+      data: channels,
       top: LAYOUT.legendTop,
       itemGap: 32,
       textStyle: { fontFamily: FONT, fontSize: 13 },