visual studio 2010 - WPF styles not being applied from App.xaml -

i'm looking apply styling wpf controls can done css in html.

this first dabbling in wpf , i've collected need in app.xaml. below i've got.

i've tried targettype="{x:type tabitem}" , targettype="tabitem".

none of styles i've defined being applied.

app.xaml

<application x:class="vmware_lab_manager_desktop.app"              xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"              startupuri="mainwindow.xaml">     <application.resources>         <resourcedictionary source="styles.xaml"></resourcedictionary>     </application.resources> </application> 

styles.xaml

<resourcedictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">     <style targettype="{x:type tabcontrol}">         <setter property="background">             <setter.value>                 <lineargradientbrush endpoint="0.5,1" startpoint="0.5,0">                     <gradientstop color="#ff464646" offset="0" />                     <gradientstop color="#ff2d2d2d" offset="0.5" />                     <gradientstop color="#ff141414" offset="1" />                 </lineargradientbrush>             </setter.value>         </setter>     </style>      <style targettype="{x:type tabitem}">         <setter property="background">             <setter.value>                 <lineargradientbrush endpoint="0.5,1" startpoint="0.5,0">                     <gradientstop color="#ff464646" offset="0" />                     <gradientstop color="#ff2d2d2d" offset="0.5" />                     <gradientstop color="#ff141414" offset="1" />                 </lineargradientbrush>              </setter.value>         </setter>         <setter property="borderbrush">             <setter.value>                 <lineargradientbrush endpoint="1,0.5" startpoint="0,0.5">                     <gradientstop color="black" offset="0" />                     <gradientstop color="#ff464646" offset="1" />                 </lineargradientbrush>             </setter.value>         </setter>     </style>      <style targettype="{x:type window}">         <setter property="background">             <setter.value>                 <lineargradientbrush endpoint="1,0.5" startpoint="0,0.5">                     <gradientstop color="#ff2d2d2d" offset="0.5" />                     <gradientstop color="#ff141414" offset="0" />                     <gradientstop color="#ff464646" offset="1" />                 </lineargradientbrush>             </setter.value>         </setter>     </style> </resourcedictionary> 

mainwindow.xaml

<window x:class="vmware_lab_manager_desktop.mainwindow"         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"         title="mainwindow" height="456" width="803" padding="0" margin="0">      <tabcontrol horizontalalignment="stretch" margin="0" padding="0" name="tabcontrol1" verticalalignment="stretch" borderthickness="0" tabstripplacement="bottom">         <tabitem name="tabitem1" header="...">             <webbrowser  horizontalalignment="stretch" name="webbrowser1" margin="0" verticalalignment="stretch" source="http://www.msdn.com/" />         </tabitem>         <tabitem header="+" />     </tabcontrol> </window> 

 <application.resources>     <resourcedictionary>         <resourcedictionary.mergeddictionaries>             <resourcedictionary source="style.xaml" />         </resourcedictionary.mergeddictionaries>     </resourcedictionary> </application.resources>