To quote official article:
Land.io is a responsive HTML template, with focus on simplicity, performance and usability. Built on top of Bootstrap 4, it was developed using Sass (new Bootstrap standard) and many of its components and utilities.
Also, we integrated frontend admin panel. Take a look:
https://dl.dropbox.com/s/xue6upoz5avf0z5/Landio__Free_Landing_Page_HTML_Template_2015-11-10_13-39-42.png
Of course as always we included few awesome layout templates. Enjoy :) :)
http://demo.getgrav.org/landio-skeleton/
https://github.com/getgrav/grav-skeleton-landio-site
https://github.com/getgrav/grav-theme-landio