Problem with selection styling.

Hi.
I'm trying to create a button which will apply some CSS class (defined externally), atm I've create this plugin:

var FCKCode=function(name){
        this.Name=name;
};

FCKCode.prototype.Execute=function(){
        FCKUndo.SaveUndoStep();

        var style=new FCKStyle({Element: 'span',Styles: {'background-color': 'red'}});
        alert(FCK.Styles.CheckStyleInSelection(style));
        if(FCK.Styles.CheckStyleInSelection(style))
                FCK.Styles.RemoveStyle(style);
        else FCK.Styles.ApplyStyle(style);

        FCKUndo.SaveUndoStep();
        FCK.Focus();
        FCK.Events.FireEvent('OnSelectionChange');
};

FCKCode.prototype.GetState=function(){
        if(FCK.EditMode!=FCK_EDITMODE_WYSIWYG||!FCK.EditorDocument)
                return FCK_TRISTATE_DISABLED;

        if(FCKSelection.GetType()=='Control'){
                var el=FCKSelection.GetSelectedElement();
                if(!el||!FCKStyles.CheckHasObjectStyle(el.nodeName.toLowerCase()))
                        return FCK_TRISTATE_DISABLED;
        }
        return FCK_TRISTATE_OFF;
};

FCKCommands.RegisterCommand('Code',new FCKCode('Code'));

var oCodeItem=new FCKToolbarButton('Code','Code',null,null,false,true);
oCodeItem.IconPath=FCKConfig.PluginsPath+'code/Code.gif';
FCKToolbarItems.RegisterItem('Code',oCodeItem);

Added Code.gif icon to plugin folder and registered it:

FCKConfig.Plugins.Add('code');

Button shows correctly and fires Execute on click.
But I don't understand how do I:

• Make it work with external style (in CSS file).


• Figure out is this style already applied.


• Correctly remove the style.

Thanks for answers.