improved CM

Signed-off-by: zhangtianli2006 <49156174+zhangtianli2006@users.noreply.github.com>

Author: ZTL-UwU

src/assets/code_mirror/tomorrow.css

@@ -65,11 +65,17 @@
 }
 
 .CodeMirror-matchingbracket {
-    color: #8e908c !important;
+    color: #4d4d4c !important;
     outline: 1px solid #d6d6d6;
     -moz-outline-radius: 3px;
 }
 
+.CodeMirror-nonmatchingbracket {
+    color: #c82829 !important;
+    outline: 1px solid #c82829;
+    -moz-outline-radius: 3px;
+}
+
 .CodeMirror-foldmarker {
     text-shadow: none !important;
     color: #8e908c !important;