[improvement] IndexBar: add default highlight color and more less vars

packages/index-bar/en-US.md

@@ -65,7 +65,7 @@ export default {
 | index-list | Index List | `Array` | `A-Z` |
 | z-index | z-index | `Number` | `1` |
 | sticky | Whether to enable anchor sticky top | `Boolean` | `true` |
-| highlight-color | Index character highlight color | `String` | - | - |
+| highlight-color | Index character highlight color | `String` | `#07c160` | - |
 
 ### IndexAnchor Props
 

packages/index-bar/index.js

@@ -1,6 +1,7 @@
 import { use } from '../utils';
 import { TouchMixin } from '../mixins/touch';
 import { ParentMixin } from '../mixins/relation';
+import { GREEN } from '../utils/color';
 import { on, off } from '../utils/event';
 import { getScrollTop, getElementTop, getScrollEventTarget } from '../utils/scroll';
 
@@ -18,7 +19,10 @@ export default sfc({
       type: Number,
       default: 1
     },
-    highlightColor: String,
+    highlightColor: {
+      type: String,
+      default: GREEN
+    },
     indexList: {
       type: Array,
       default() {

packages/index-bar/zh-CN.md

@@ -69,7 +69,7 @@ export default {
 | index-list | 索引字符列表 | `Array` | `A-Z` | - |
 | z-index | z-index 层级 | `Number` | `1` | - |
 | sticky | 是否开启锚点自动吸顶 | `Boolean` | `true` | - |
-| highlight-color | 索引字符高亮颜色 | `String` | - | - |
+| highlight-color | 索引字符高亮颜色 | `String` | `#07c160` | - |
 
 ### IndexAnchor Props