diff --git a/src/panel/less/panel.less b/src/panel/less/panel.less
index 79e60692..2d24e45e 100644
--- a/src/panel/less/panel.less
+++ b/src/panel/less/panel.less
@@ -8,7 +8,6 @@
 .mdui-panel {
   box-sizing: border-box;
   width: 100%;
-  .mdui-shadow(2);
 }
 
 /* 面板项 */
@@ -18,10 +17,11 @@
   height: 48px;
   overflow: hidden;
   .mdui-divider-bottom-dark();
-  will-change: height, margin-top, margin-bottom;
-  transition-property: height, margin-top, margin-bottom;
+  will-change: height, margin;
+  transition-property: height, margin;
   transition-duration: .3s;
   transition-timing-function: @animation-curve-default;
+  .mdui-shadow(2);
 
   &:last-child {
     border-bottom: none;
@@ -31,6 +31,8 @@
 /* 打开状态的面板项 */
 .mdui-panel-item-open {
   height: auto;
+  margin-top: 16px;
+  margin-bottom: 16px;
 }
 
 /* 面板头部 */
@@ -112,17 +114,25 @@
   }
 }
 
-/* 使打开项拥有上下边距 */
-.mdui-panel-popout {
-  .mdui-shadow(0);
+/* 使打开项上下没有边距 */
+.mdui-panel-gapless {
+  .mdui-shadow(2);
 
   .mdui-panel-item {
-    .mdui-shadow(2);
+    .mdui-shadow(0);
   }
 
   .mdui-panel-item-open {
-    margin-top: 16px;
-    margin-bottom: 16px;
+    margin-top: 0;
+    margin-bottom: 0;
+  }
+}
+
+/* 弹出面板 */
+.mdui-panel-popout {
+  .mdui-panel-item-open {
+    margin-left: -16px;
+    margin-right: -16px;
   }
 }