diff --git a/app/src/assets/scss/base.scss b/app/src/assets/scss/base.scss
index c82de79fd..0ce5c1953 100644
--- a/app/src/assets/scss/base.scss
+++ b/app/src/assets/scss/base.scss
@@ -43,7 +43,11 @@
 
 .side-mask: 6
 
-#menu & .side-panel: 7
+Mobile #menu & .side-panel: 7
+
+.fullscreen: 8
+
+ window.siyuan.zIndex: 10
 
 #windowControls: 999998
 
@@ -65,7 +69,7 @@ html {
   width: 100% !important;
   left: 0;
   height: 100vh !important;
-  z-index: 90;
+  z-index: 8;
   border-radius: 0;
 
   & > .protyle-breadcrumb,