Leopard-Steel is light Mac desktop related theme, It is designed for GTK 3.6/3.3 and also support GTK-2. It is designed for those who like Mac-Leopard desktop. This is different from Mac-OS-X theme, If you want to transform your Ubuntu into Mac then checkout these themes (Ubuntu 12.10, Ubuntu 12.04). Also check themes collection.
1st: zonColor Wallpapers used in Screenshot
2nd: zonColor-Icons used in Screenshot
3rd: You can use Gnome-tweak-tool or Ubuntu-Tweak to change themes
To install Leopard-Steel theme in Ubuntu/Linux Mint open Terminal (Press Ctrl+Alt+T) and copy the following commands in the Terminal: