fix(tabs): animated tabs style (#6855), close #6804

Author: kovsu

components/tabs/style/index.ts

@@ -834,7 +834,12 @@ const genTabsStyle: GenerateStyle<TabsToken> = (token: TabsToken): CSSObject =>
       // =========================== TabPanes ===========================
       [`${componentCls}-content`]: {
         position: 'relative',
+        display: 'flex',
         width: '100%',
+
+        ['&-animated']: {
+          transition: 'margin 0.3s',
+        },
       },
 
       [`${componentCls}-content-holder`]: {
@@ -845,9 +850,8 @@ const genTabsStyle: GenerateStyle<TabsToken> = (token: TabsToken): CSSObject =>
 
       [`${componentCls}-tabpane`]: {
         outline: 'none',
-        '&-hidden': {
-          display: 'none',
-        },
+        flex: 'none',
+        width: '100%',
       },
     },