diff --git a/layouts/partials/post.html b/layouts/partials/post.html
index 550fb87..358d50c 100644
--- a/layouts/partials/post.html
+++ b/layouts/partials/post.html
@@ -70,8 +70,8 @@
         async>
 </script> -->
 <script>
-	this.systemThemeMediaQuery = window.matchMedia('(prefers-color-scheme: dark)');
-    var systemTheme = this.systemThemeMediaQuery.matches ? 'dark' : 'light';
+	var systemThemeMediaQuery = window.matchMedia('(prefers-color-scheme: dark)');
+	var systemTheme = systemThemeMediaQuery.matches ? 'dark' : 'light';
 	var utterancesTheme = systemTheme === 'dark' ? 'github-dark' : 'github-light';
 	var utterancesScript = document.createElement('script');
 	utterancesScript.src = 'https://utteranc.es/client.js';
diff --git a/layouts/partials/user-profile.html b/layouts/partials/user-profile.html
index 94ea709..64e2cf6 100644
--- a/layouts/partials/user-profile.html
+++ b/layouts/partials/user-profile.html
@@ -88,7 +88,12 @@
                 {{ if .Site.Params.github}}
                 <a class="avatar-group-item" data-hovercard-type="organization"
                     href="https://github.com/{{ .Site.Params.github }}">
-                    <img src="{{ "images/github.png" | absURL }}" class="avatar" width="35" height="35">
+                    <svg width="35" height="35" class="avatar github-octicon" viewBox="0 0 16 16" version="1.1"
+                        aria-hidden="true">
+                        <path fill-rule="evenodd"
+                            d="M8 0C3.58 0 0 3.58 0 8c0 3.54 2.29 6.53 5.47 7.59.4.07.55-.17.55-.38 0-.19-.01-.82-.01-1.49-2.01.37-2.53-.49-2.69-.94-.09-.23-.48-.94-.82-1.13-.28-.15-.68-.52-.01-.53.63-.01 1.08.58 1.23.82.72 1.21 1.87.87 2.33.66.07-.52.28-.87.51-1.07-1.78-.2-3.64-.89-3.64-3.95 0-.87.31-1.59.82-2.15-.08-.2-.36-1.02.08-2.12 0 0 .67-.21 2.2.82.64-.18 1.32-.27 2-.27.68 0 1.36.09 2 .27 1.53-1.04 2.2-.82 2.2-.82.44 1.1.16 1.92.08 2.12.51.56.82 1.27.82 2.15 0 3.07-1.87 3.75-3.65 3.95.29.25.54.73.54 1.48 0 1.07-.01 1.93-.01 2.2 0 .21.15.46.55.38A8.013 8.013 0 0016 8c0-4.42-3.58-8-8-8z">
+                        </path>
+                    </svg>
                 </a>
                 {{ end }}
                 {{ if .Site.Params.misskey}}
diff --git a/static/css/dark.css b/static/css/dark.css
index 8f7b297..14d6eec 100644
--- a/static/css/dark.css
+++ b/static/css/dark.css
@@ -132,6 +132,12 @@ a {
   box-shadow: none;
 }
 
+.user-profile-sticky-bar::after {
+  background-color: rgb(24, 26, 27);
+  border-bottom-color: rgb(55, 61, 69);
+  box-shadow: rgba(0, 0, 0, 0.07) 0px 1px 2px;
+}
+
 .user-profile-nav {
   background-color: rgb(24, 26, 27);
   border-bottom-color: rgb(55, 61, 69);
@@ -225,3 +231,10 @@ a {
   border-bottom-color: initial;
   border-left-color: initial;
 }
+
+/* custom */
+
+.github-octicon {
+  fill: currentColor;
+  color: #fff;
+}