Cascading Style Sheets (CSS) is a language for describing how content is presented. Its purpose is help separating content (HTML) from presentation. OutSystems uses the Silk framework (except for the themes based on London theme) and each theme has its own CSS. You can either add new styles or modify the existing ones by copying them from the base theme.
These elements have their own CSS which you can edit:
- Web Screens and Emails
- Web Blocks
- Widgets (complex widgets have more than one style)
Applying CSS with the class attribute
You can specify classes of an element in the Properties Pane either by using the Style Classes or by using the Extended Properties and setting the
Property field as
To specify static classes using Style Classes:
- In Web Applications insert the class names without quotes and separated by a space (
- In Mobile Applications insert the class names with quotes and separated by a space (
To specify dynamics classes:
- In Web Applications use an Expression to define the
classattribute in the Extended Properties
- In Mobile Applications use an Expression in the Style Classes field
CSS is edited in Style Sheet Editor. You can open it by double-clicking Style Classes property in Properties Pane when you edit an element that can have CSS.
You can also open Style Sheet Editor by clicking the CSS button in the Main Editor toolbar. Select the tab with the application name and define or edit the style to make it available to the whole application. Alternatively, select the tab with the name of the currently selected screen or block to narrow the scope of the style to that screen or block.
Not all styles have the same priority and the order Service Studio imports the style sheets will affect how browsers will apply your styles. The last style to be applied has the highest priority.
- System style sheet for Container widgets in the Grid
- Web Blocks style sheet
- Theme style sheet, which also includes a base theme (if specified)
- Web Screens or Emails style sheet
- Theme extra style sheet, with the Grid settings defined in the Theme properties
Note: Inline styles can be used as well and overrides other styles when the element is rendered.
To use inline CSS you can create it by adding
style in the Extended Properties and then entering the CSS rules (for example,
OutSystems uses a high-level grid system. If you specify the number of columns in the Theme grid settings, the width of elements can be expressed in columns. In some properties (for example, Margin Top), Service Studio converts
Auto indicates the values are calculated automatically.
@import CSS at-rule in Style Sheet Editor to import style rules from other locations.