Skin archive have to be zip archive and contains files:

• styles.css - main skin file. This in only file plugged in.
• info.json - skin info file (name, author, contacts, version, link, description).
• preview.png - preview image with 1200 x 600 page size and on main demo page with default menu logined by user Admin.
• readme.md - information about skin
• Css source files (scss recomended) [if needed]
• Images files [if needed]
• Fonts files [if needed]

All skins available for free use.
All skins are going at SunEngine License.

Russian documentation on main site.