diff --git a/lib/task.js b/lib/task.js
index 557e233..ce32175 100644
--- a/lib/task.js
+++ b/lib/task.js
@@ -30,11 +30,27 @@ exports.build = function (opts) {
     components = config.components.concat(['base'])
     cssFiles = '{' + components.join(',') + '}'
   }
+
   var varsPath = path.resolve(config.themePath, './src/common/var.scss')
-  fs.writeFileSync(varsPath, fs.readFileSync(path.resolve(process.cwd(), opts.config || config.config)), 'utf-8')
+  var customPath = path.resolve(process.cwd(), opts.config || config.config)
+  var varsContent = fs.readFileSync(customPath, 'utf8') + fs.readFileSync(varsPath, 'utf8')
 
   stream = gulp.src([opts.config || config.config, path.resolve(config.themePath, './src/' + cssFiles + '.scss')])
-    .pipe(sass.sync())
+    .pipe(sass.sync({
+      importer: function (url, prev) {
+        var dir = path.dirname(prev)
+        var file = path.resolve(dir, url)
+        if (!file.endsWith('.scss')) {
+          file += '.scss'
+        }
+        if (file === varsPath) {
+          return {
+            contents: varsContent
+          }
+        }
+        return null
+      }
+    }))
     .pipe(autoprefixer({
       browsers: config.browsers,
       cascade: false