Add strikethrough to checked checkbox

I am trying to add strikethrough when i select a checkbox in my form (Bootstrap v3). I coded this bootply:

<div class="form-group "><label for="inputName" class="col-md-1 control-label">select</label>  <div class="col-md-5"><div class="checkbox"><label><input type="checkbox" name="packersOff" class="strikethrough" value="1">sssssssss</label></div></div></div>

and added a class in css

.strikethrough:checked{  text-decoration:line-through;}

but it doesn't work..