OO.ui demo
Using OOUI widgets
Depending on which of the features you're going to use, you should list one or more of the following modules as dependencies of your modules that use OOUI:
oojs-ui-core— OOUI's core JavaScript library. Contains the basic widgets and layouts that are also available in PHP (see exact list above) and the ability to infuse them.oojs-ui-widgets— Additional widgets and layouts.oojs-ui-toolbars— Toolbar and tools.oojs-ui-windows— Windows and dialogs.oojs-ui.styles.icons-*— Specific icon styles depending on what icons you may want to use, e.g.oojs-ui.styles.icons-interactionsfor check icon. Group names can be found in demo page or in code.