Theming is as simple as writing a tiny css file that will override the default style variables defined in _vars.scss :

:root {

This will change the default accent color to red. Variables can also be overridden for a specific subset of elements, for example :

.panel-container {

This will change the default text color to blue for all elements in panel widgets.

Of course, regular css is also allowed :

.widget .input {
    display: none;

This will hide the widgets' value inputs.