🐛[Dropdown]修改 dropdown 层级

Author: liyuan-meng

src/components/c-dropdown/index.less

@@ -34,7 +34,7 @@
   width: fit-content;
   min-width: fit-content !important;
 
-  z-index: @z-index-dropdown;
+  z-index: 1;
 
   &-menu-area {
     border-radius: 6px;
@@ -188,3 +188,12 @@
 .@{dropdown-prefix-cls}-slide-up-enter {
   opacity: 1;
 }
+
+.@{dropdown-prefix-cls}-placement-top,
+.@{dropdown-prefix-cls}-placement-topLeft,
+.@{dropdown-prefix-cls}-placement-topRight,
+.@{dropdown-prefix-cls}-placement-bottom,
+.@{dropdown-prefix-cls}-placement-bottomLeft,
+.@{dropdown-prefix-cls}-placement-bottomRight {
+  z-index: @z-index-dropdown;
+}