dx.ui.js

	$.fn.load_feature_content = function(obj, contents) {
		var feature, feature_content;
		contents.hide();
		var items = ["active", "before-active", "after-active"];
		for(i in items){
			var item = items[i];
			this.parent().find("."+item).removeClass(item);
		}
		this.addClass("active");
		this.next().addClass("after-active");
		this.prev().addClass("before-active");
		feature = $(this).attr("data-feature");
		feature_content = obj.find("div[data-feature=" + feature + "]");
		feature_content.show();
	};

sombrinhas.css

.features-panel .feature-list li.before-active{
    box-shadow: inset -2px -23px 15px -25px;
}

.features-panel .feature-list li.before-active a{
	border-bottom: none;
}

.features-panel .feature-list li.active a{
	border: none;
}
.features-panel .feature-list li.active {
	background-color: #fff;
	background-image: none;
}

.features-panel .feature-list li.after-active {
	box-shadow: inset -2px 20px 15px -25px;
}