fix(jqLite): .css() retrieves computed style also

src/jqLite.js

@@ -512,7 +512,20 @@ forEach({
         if (val === '') val = 'auto';
       }
 
-      val = val || element.style[name];
+      var contains =  function (a, b){
+        // jshint bitwise: false
+        return a.contains ?
+          a != b && a.contains(b) :
+          !!(a.compareDocumentPosition(b) & 16);
+      };
+
+      var elementWindow = element.ownerDocument.defaultView || element.ownerDocument.parentWindow;
+      // if browser supports getComputedStyle and element attached to body
+      if (isDefined(elementWindow.getComputedStyle) && contains(element.ownerDocument, element)) {
+        val = val || elementWindow.getComputedStyle(element, null)[name];
+      } else {
+        val = val || element.style[name];
+      }
 
       if (msie <= 8) {
         // jquery weirdness :-/

test/jqLiteSpec.js

@@ -825,6 +825,19 @@ describe('jqLite', function() {
       }
     });
 
+    it('should get computed styles', function() {
+      if (window.getComputedStyle) { // browser should support of computed styles
+        a.id = 'elementA';
+        var jqA = jqLite(a);
+        jqLite(document).find('body').append(jqA);
+
+        var style = document.createElement('style');
+        style.appendChild(document.createTextNode('#elementA { width: 25px; }'));
+        jqLite(document).find('head').append(style);
+
+        expect(jqA.css('width')).toBe('25px');
+      }
+    });
 
     it('should set a bunch of css properties specified via an object', function() {
       if (msie <= 8) {