fix

@@ -140,7 +140,7 @@ export default {
       if (this.scrollTop > this.coverHeight) {
         return 100;
       } else if (this.scrollTop > 0) {
-        let step = Math.round(this.scrollTop - 10 / (this.coverHeight - 10) * 100);
+        let step = Math.round((this.scrollTop - 10) / (this.coverHeight - 90) * 100);
 
         step = Math.max(Math.min(step, 100), 0);
         this.SET_STATUS_BAR_COLOR({