DarkLite is a nice and very friendly design, fulfilling the expectations of any MyBB forum, DarkLite is totally responsive adapting to mobile devices.

Global variables are used in CSS to facilitate changing colors.

• Easy to install and use.
• Pure CSS, nothing bootstrap. 
• Super fast charging on all devices. 
• Responsive design Many rebuilt parts, to make it modern.
• Variables of css to facilitate the change of colors. 
• Use of FontAwesome icons. 
• Supports mybb plugins. 
• Good documentation 
• A good support.

Have installed mybb >= 1.8.26
Have knowledge in html and css (not mandatory)

Install the theme (admin -> Templates & Style -> Import a Theme) And finally activate the theme.

If you don't know how to install the theme or have a problem, check the documentation.