Error when compile valo theme in command prompt

I’m developing a vaadin application which used vaadin v7.2. Now it is updated to v7.3.7 and used the new valo theme with my custom styles. When compiling the whole project using mvn clean install the theme getting compile perfectly. But when I try to compile the theme using command prompt with below command

    java -cp '../../../../../../target/product-webapp-*' com.vaadin.sass.SassCompiler styles.scss styles.css

it pushes a valo not found error like below Import '../valo/valo.scss' in '/home/lahirub/Documents/PROJECTS/NewClearProduct/newclear-product-webapp/src/main/webapp/VAADIN/themes/mytheme/styles.scss' could not be found
    com.vaadin.sass.internal.parser.ParseException: Mixin Definition: valo not found

My custom theme is like this


  @import "../valo/valo.scss";
    @mixin mytheme {
      @include valo;
      // Insert your own theme rules here



@import “mytheme.scss”;
@import “addons.scss”;

// This file prefixes all rules with the theme name to avoid causing conflicts with other themes.
// The actual styles should be defined in mytheme.scss

.mytheme {
  @include addons;
  @include mytheme;





/* Import and include this mixin into your project theme to include the addon themes */
@mixin addons {

I’m unable to find the reason for this error. Can anyone please give me some suggestion.