diff --git a/public/css/extra.css b/public/css/extra.css
index 186eb91..2b5091d 100644
--- a/public/css/extra.css
+++ b/public/css/extra.css
@@ -272,6 +272,30 @@ h6:hover .header-link {
     padding-right: 38px;
 }
 
+/* support japanese font */
+.markdown-body[lang^="ja"] {
+    font-family: "Helvetica Neue", Helvetica, Arial, Meiryo, "MS Gothic", "ＭＳ ゴシック", sans-serif;
+}
+.ui-toc-dropdown[lang^="ja"] {
+    font-family: "Source Sans Pro", Helvetica, Arial, "Meiryo UI", "MS PGothic", "ＭＳ Ｐゴシック", sans-serif;
+}
+
+/* support zh-tw font */
+.markdown-body[lang="zh-tw"] {
+    font-family: "Helvetica Neue", Helvetica, Arial, "Microsoft JhengHei", "微軟正黑", sans-serif;
+}
+.ui-toc-dropdown[lang="zh-tw"] {
+    font-family: "Source Sans Pro", Helvetica, Arial, "Microsoft JhengHei UI", "微軟正黑UI", sans-serif;
+}
+
+/* support zh-cn font */
+.markdown-body[lang="zh-cn"] {
+    font-family: "Helvetica Neue", Helvetica, Arial, "Microsoft YaHei", "微软雅黑", sans-serif;
+}
+.ui-toc-dropdown[lang="zh-cn"] {
+    font-family: "Source Sans Pro", Helvetica, Arial, "Microsoft YaHei UI", "微软雅黑UI", sans-serif;
+}
+
 .ui-affix-toc {
     position: fixed;
     top: 0;
diff --git a/public/css/html.min.css b/public/css/html.min.css
index 26cb7da..3f938f7 100644
--- a/public/css/html.min.css
+++ b/public/css/html.min.css
@@ -1 +1 @@
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diff --git a/public/css/markdown.css b/public/css/markdown.css
index f9009d5..f54d163 100644
--- a/public/css/markdown.css
+++ b/public/css/markdown.css
@@ -1,7 +1,7 @@
 /* for markdown-body */
 
 .markdown-body {
-    font-family: "Helvetica Neue", Helvetica, Arial, "Microsoft JhengHei", Meiryo, "ＭＳ ゴシック", "MS Gothic", sans-serif;
+    font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
     padding-top: 40px;
     padding-bottom: 40px;
     max-width: 758px;
diff --git a/public/css/site.css b/public/css/site.css
index a6c0f3a..7b56935 100644
--- a/public/css/site.css
+++ b/public/css/site.css
@@ -7,7 +7,7 @@ body {
     text-shadow: 1px 1px 1px rgba(0, 0, 0, 0.004);
     /*text-rendering: optimizeLegibility;*/
     -webkit-overflow-scrolling: touch;
-    font-family: "Source Sans Pro", Helvetica, Arial, "Microsoft JhengHei UI", "Meiryo UI", "ＭＳ Ｐゴシック", "MS PGothic", sans-serif;
+    font-family: "Source Sans Pro", Helvetica, Arial, sans-serif;
     letter-spacing: 0.025em;
 }
 :focus {