You'll have to download another Splunk version and install it in a different directory. Then copy over the application.css file from $SPLUNK_HOME/etc/apps/search/appserver/static. Once you're done, you can delete the extra version of Splunk.
You'll have to download another Splunk version and install it in a different directory. Then copy over the application.css file from $SPLUNK_HOME/etc/apps/search/appserver/static. Once you're done, you can delete the extra version of Splunk.