.. -*- coding: utf-8 -*-CSS Stylesheet---------------Conventions~~~~~~~~~~~XXX external_resources variable naming convention request.add_cssExtending / overriding existing styles~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~We cannot modify the order in which the application is reading the CSS. Inthe case we want to create new CSS style, the best is to define it a in a newCSS located under ``myapp/data/`` and use those new styles while writingcustomized views and templates.If you want to modify an existing CSS styling property, you will have to use``!important`` declaration to override the existing property. The applicationapply a higher priority on the default CSS and you can not change that.Customized CSS will not be read first.CubicWeb stylesheets~~~~~~~~~~~~~~~~~~~~XXX explain diffenrent files and main classes