diff --git a/heatcalc/index.css b/heatcalc/heatcalc.css
similarity index 100%
rename from heatcalc/index.css
rename to heatcalc/heatcalc.css
diff --git a/heatcalc/index.js b/heatcalc/heatcalc.js
similarity index 100%
rename from heatcalc/index.js
rename to heatcalc/heatcalc.js
diff --git a/heatcalc/index.html b/heatcalc/index.html
index e8e548e..c21b140 100644
--- a/heatcalc/index.html
+++ b/heatcalc/index.html
@@ -1,4 +1,5 @@
 <script src="require.js"></script>
+<link rel="stylesheet" href="heatcalc.css">
 <script>
   require(['heatcalc'], function (hc) {
       hc.init("<?php echo $block->getFileUrl('data.json');?>");