diff --git a/src/echarts.js b/src/echarts.js
index 4ffb210f14a8a728322a4aa9006482f8a5f60c4c..2576dabf5292d750cbd5a403b77e63deb2699a7e 100644
--- a/src/echarts.js
+++ b/src/echarts.js
@@ -1307,6 +1307,7 @@ define(function (require) {
     echarts.format = require('./util/format');
     echarts.matrix = require('zrender/core/matrix');
     echarts.vector = require('zrender/core/vector');
+    echarts.color = require('zrender/core/color');
 
     echarts.util = {};
     each([
diff --git a/src/visual/seriesColor.js b/src/visual/seriesColor.js
index 350b595d7875eb4a1095c6a072c2583835888257..4aa6303f5b700a18619207f7f0cf7b0a795551a1 100644
--- a/src/visual/seriesColor.js
+++ b/src/visual/seriesColor.js
@@ -20,6 +20,7 @@ define(function (require) {
                     });
                 }
 
+                // itemStyle in each data item
                 data.each(function (idx) {
                     var itemModel = data.getItemModel(idx);
                     var color = itemModel.get(colorAccessPath, true);