webui may be modified with custom style.css

src/resources/index.html

@@ -14,6 +14,7 @@
  <script src="/js/Chart.min.js"></script>
  <script src="/js/Chart.HorizontalBar.js"></script>
  <link href="/css/bootstrap.min.css" rel="stylesheet">
+ <link href="/custom/style.css" rel="stylesheet">
  <script src="/js/app.js" defer></script>
  <style>
   body, html { height: 100%; }