diff --git a/lang/zh-hans.css b/lang/zh-hans.css
new file mode 100644
index 0000000..b5ccbd3
--- /dev/null
+++ b/lang/zh-hans.css
@@ -0,0 +1,5 @@
+:lang(zh-hans) .theorem::before { content: '定理 ' counter(theorem) '. ' !important; }
+:lang(zh-hans) .lemma::before { content: '引理 ' counter(theorem) '. ' !important; }
+:lang(zh-hans) .proof::before { content: '证明：' attr(title) !important; font-style: normal; }
+:lang(zh-hans) .definition::before { content: '定义 ' counter(definition) '. ' !important; }
+:lang(zh-hans) ::before { font-family: 'Microsoft Yahei', 'STHeiti', 'Source Han Sans CN'; }
\ No newline at end of file
diff --git a/lang/zh-hant.css b/lang/zh-hant.css
new file mode 100644
index 0000000..4616f2c
--- /dev/null
+++ b/lang/zh-hant.css
@@ -0,0 +1,5 @@
+:lang(zh-hant) .theorem::before { content: '定理 ' counter(theorem) '. ' !important; }
+:lang(zh-hant) .lemma::before { content: '引理 ' counter(theorem) '. ' !important; }
+:lang(zh-hant) .proof::before { content: '證明：' attr(title) !important; font-style: normal; }
+:lang(zh-hant) .definition::before { content: '定義 ' counter(definition) '. ' !important; }
+:lang(zh-hant) ::before { font-family: 'Microsoft Yahei', 'STHeiti', 'Source Han Sans CN'; }
\ No newline at end of file
diff --git a/languages.html b/languages.html
index 85f0e51..2152832 100644
--- a/languages.html
+++ b/languages.html
@@ -49,6 +49,8 @@
       <option value="mwl">Mirandese (mwl)</option>
       <option value="pt">Portuguese (pt)</option>
       <option value="ro">Romanian (ro)</option>
+      <option value="zh-hans">Simplified Chinese (zh-hans)</option>
+      <option value="zh-hant">Traditional Chinese (zh-hant)</option>
     </select>
 
     <div id="wrapper">