add CssVar

packages/artplayer/src/index.js

@@ -192,6 +192,7 @@ export default class Artplayer extends Emitter {
             },
             i18n: {},
             icons: {},
+            cssVar: {},
             customType: {},
             lang: navigator.language.toLowerCase(),
         };

packages/artplayer/src/scheme/index.js

@@ -118,5 +118,6 @@ export default {
     moreVideoAttr: o,
     i18n: o,
     icons: o,
+    cssVar: o,
     customType: o,
 };