public static Object getStyleForClasses( Object styleClass, String type )
		throws IllegalArgumentException
	{
		if( styleClass == null )
			return null;

		if( styleClass instanceof String && ((String)styleClass).indexOf( ' ' ) >= 0 )
			styleClass = StringUtils.split( (String) styleClass, ' ', true, true );

		if( styleClass instanceof String )
			return getStyleForClass( ((String)styleClass).trim(), type );
		else if( styleClass instanceof String[] ) {
			Object style = null;
			for( String cls : (String[]) styleClass )
				style = joinStyles( style, getStyleForClass( cls, type ) );
			return style;
		} else if( styleClass instanceof List<?> ) {
			Object style = null;
			for( Object cls : (List<?>) styleClass )
				style = joinStyles( style, getStyleForClass( (String) cls, type ) );
			return style;
		} else
			return null;
	}
Returns the styles for the given style class(es) and the given type.
<p>
The style rules must be defined in UI defaults either as strings (in CSS syntax)
or as {@link java.util.Map}&lt;String, Object&gt; (with binary values).
The key must be in syntax: {@code [style]type.styleClass}, where the type is optional.
E.g. in FlatLaf properties file:
<pre>{@code
[style]Button.primary = borderColor: #08f; background: #08f; foreground: #fff
[style].secondary = borderColor: #0f8; background: #0f8
}</pre>
or in Java code:
<pre>{@code
UIManager.put( "[style]Button.primary", "borderColor: #08f; background: #08f; foreground: #fff" );
UIManager.put( "[style].secondary", "borderColor: #0f8; background: #0f8" );
}</pre>
The rule "Button.primary" can be applied to buttons only.
The rule ".secondary" can be applied to any component.
<p>
To have similar behavior as in CSS, this method first gets the rule without type,
then the rule with type and concatenates both rules.
E.g. invoking this method with parameters styleClass="foo" and type="Button" does following:
<pre>{@code
return joinStyles(
    UIManager.get( "[style].foo" ),
    UIManager.get( "[style]Button.foo" ) );
}</pre>

@param styleClass the style class(es) either as string (single class or multiple classes separated by space characters)
                  or as {@code String[]} or {@link java.util.List}&lt;String&gt; (multiple classes)
@param type the type of the component
@return the styles
flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatStylingSupport.java