Standardize financial chart colors and improve label placement

js/charts/ppmt_bridge.js

@@ -1,6 +1,6 @@
 import { col } from '../csv.js';
 import {
-  PALETTE, FONT, axisCommon, titleStyle, footnote, watermarks,
+  PALETTE, BRIDGE_COLORS, FONT, axisCommon, titleStyle, footnote, watermarks,
 } from '../theme.js';
 
 /**
@@ -13,12 +13,6 @@ import {
  * 税率变化单独成项。恒等式 净利率 = 税前利润率 × (1-税率)，
  * Δ净 = Δ税前×(1-t₁) − 税前₂×Δt，实测闭合误差 0.00pct。
  */
-const COLOR = {
-  total: '#2F5C85',   // 首尾锚点
-  neg:   '#C0392B',   // 拖累
-  pos:   '#1A9E5C',   // 利好
-};
-
 export function ppmtBridgeChart(rows, { width, height }) {
   const items = col(rows, 'item');
   const types = col(rows, 'type');
@@ -92,7 +86,7 @@ export function ppmtBridgeChart(rows, { width, height }) {
         barWidth: 51,
         data: values.map((v, i) => ({
           value: v,
-          itemStyle: { color: COLOR[types[i]] },
+          itemStyle: { color: BRIDGE_COLORS[types[i]] },
         })),
         label: {
           show: true,