[Doc] update neutral color variables (#2130)

packages/circle/demo/index.vue

@@ -14,7 +14,7 @@
         fill="#fff"
         :rate="rate"
         size="120px"
-        layer-color="#eee"
+        layer-color="#ebedf0"
         :speed="100"
         :stroke-width="60"
         :clockwise="false"

packages/circle/en-US.md

@@ -43,7 +43,7 @@ export default {
   color="#13ce66"
   fill="#fff"
   size="120px"
-  layer-color="#eee"
+  layer-color="#ebedf0"
   :text="text"
   :rate="rate"
   :speed="100"

packages/circle/test/__snapshots__/demo.spec.js.snap

@@ -12,7 +12,7 @@ exports[`renders demo correctly 1`] = `
     </div>
     <div class="van-circle" style="width:120px;height:120px;">
       <svg viewBox="0 0 1060 1060">
-        <path d="M 530 530 m -500, 0 a 500, 500 0 1, 1 1000, 0 a 500, 500 0 1, 1 -1000, 0" class="van-circle__hover" style="fill:#fff;stroke:#eee;stroke-width:60px;"></path>
+        <path d="M 530 530 m -500, 0 a 500, 500 0 1, 1 1000, 0 a 500, 500 0 1, 1 -1000, 0" class="van-circle__hover" style="fill:#fff;stroke:#ebedf0;stroke-width:60px;"></path>
         <path d="M 530 530 m -500, 0 a 500, 500 0 1, 1 1000, 0 a 500, 500 0 1, 1 -1000, 0" class="van-circle__layer" style="stroke:#13ce66;stroke-dashoffset:3140px;stroke-width:61px;"></path>
       </svg>
       <div class="van-circle__text">0%</div>

packages/circle/zh-CN.md

@@ -44,7 +44,7 @@ export default {
   color="#13ce66"
   fill="#fff"
   size="120px"
-  layer-color="#eee"
+  layer-color="#ebedf0"
   :text="text"
   :rate="rate"
   :speed="100"