The std_style_v2 weblet takes care of creating all the <link> tags needed to load the CSS files so you need to include it in the <head> section of your layouts. The std_style_v2 weblet always loads std_style.min.css into every layout. This defines the non-theme related properties of all LANSA supplied weblets.
It then loads any CSS files defined by its theme_css_filename and css_files properties. These properties are provided for backwards compatibility with layouts built with older versions of the weblet. For new layouts, you should specify 'none' in theme_css_filename and use External Resources to define additional CSS files you want to include.
Next, it adds any CSS files defined as External Resources (which we mentioned above) referenced in the webroutine, layout or weblets used by the webroutine.
Finally, the std_style_v2 weblet loads a stylesheet defined by the variable $lweb_std_css_language_overlay. This variable is defined in the std_locale weblet and provides a means to apply language specific CSS modifications.
Before External Resources and jQuery UI support, the default LANSA theme was included in std_styles.css and always loaded. Any custom themes added with the theme_css_filename property had to take this into account and undo any styles from the default theme that they didn't want. From LANSA version 12 SP1 the styles associated with this default theme are separated into their own CSS file (theme_default.css). For backwards compatibility this theme is still loaded before any theme specified in theme_css_filename.
New themes can remove theme_default.css and start with a blank canvas by specifying 'none' in the theme_css_filename property.
The css_files property provided a mechanism for individual webroutines to add special purpose CSS files to the page such as a CSS file needed by a custom weblet. External Resources are a much more powerful mechanism for doing this, allowing weblets to define their own CSS requirements and having that automatically communicated through to std_style_v2. The css_files property is no longer necessary and is included only for backwards compatibility.
The CSS filenames passed in arguments to std_style_v2 are assumed to be relative to the style sub-directory. The value of the style sub-directory is defined by the variable $lweb_style_path. By default, this variable refers to the sub-directory /style directly under the web server image directory. We recommend that you do not change this value.
From version 13.0, WAM output is in UTF-8.
<link> elements for the ccs_files property didn't have a charset attribute, therefore they were assumed to be in the same character set as the main document. To preserve backwards compatibility, they now have a charset attribute that defaults to "shift_jis" for language JPN and to "iso-8859-1" for all other languages. If you need to nominate a different character set, use the css_files_charset property in weblet std_style_v2 (you will need to add this parameter to your site layout). A better approach is to register your extra CSS files as external resources and include them as such.