gtk2-engines-aurora software package provides Aurora gtk+-2.0 theme engine, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install gtk2-engines-aurora
gtk2-engines-aurora is installed in your system.
Make ensure the gtk2-engines-aurora package were installed using the commands given below,
$ sudo dpkg-query -l | grep gtk2-engines-aurora *
You will get with gtk2-engines-aurora package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | X Window System software |
| Package | gtk2-engines-aurora |
| Version | 1.5.1-4 |
| Description | Aurora gtk+-2.0 theme engine |
| Sub Section | X273 |