docs: fix BackTop examples hidden

close #22392

site/bisheng.config.js

@@ -134,10 +134,6 @@ module.exports = {
     if (isDev) {
       // eslint-disable-next-line
       config.devtool = 'source-map';
-
-      // Resolve use react hook fail when yarn link or npm link
-      // https://github.com/webpack/webpack/issues/8607#issuecomment-453068938
-      config.resolve.alias = { ...config.resolve.alias, react: require.resolve('react') };
     }
 
     alertBabelConfig(config.module.rules);

site/theme/static/footer.less

@@ -2,7 +2,7 @@
 @import './colors';
 
 .rc-footer {
-  z-index: 11;
+  z-index: 9;
 
   &-container {
     max-width: unset;