diff --git a/assets/css/_addon/main.scss b/assets/css/_addon/main.scss
index a30722a..7fa3b5f 100644
--- a/assets/css/_addon/main.scss
+++ b/assets/css/_addon/main.scss
@@ -46,8 +46,9 @@ html[mode=dark] {
   }
 }
 
-html, body {
+:root {
   font-size: 16px;
+  scroll-behavior: smooth;
 }
 
 body {
diff --git a/assets/js/_commons/back-to-top.js b/assets/js/_commons/back-to-top.js
index 21a91da..377e35f 100644
--- a/assets/js/_commons/back-to-top.js
+++ b/assets/js/_commons/back-to-top.js
@@ -1,9 +1,8 @@
 /*
 Reference: https://bootsnipp.com/snippets/featured/link-to-top-page
 */
-
 $(function() {
-  $(window).scroll(function() {
+  $(window).scroll(() => {
     if ($(this).scrollTop() > 50 &&
       $("#sidebar-trigger").css("display") === "none") {
       $("#back-to-top").fadeIn();
@@ -12,10 +11,8 @@ $(function() {
     }
   });
 
-  $("#back-to-top").click(function() {
-    $("body,html").animate({
-      scrollTop: 0
-    }, 800);
+  $("#back-to-top").click(() => {
+    $("body,html").scrollTop(0);
     return false;
   });
 });