Changing the img paths in the css files

plugins/ionslider/ion.rangeSlider.skinFlat.css

@@ -12,7 +12,7 @@
 .irs-bar,
 .irs-bar-edge,
 .irs-slider {
-    background: url(../img/sprite-skin-flat.png) repeat-x;
+    background: url(img/sprite-skin-flat.png) repeat-x;
 }
 
 .irs {

plugins/ionslider/ion.rangeSlider.skinNice.css

@@ -12,7 +12,7 @@
 .irs-bar,
 .irs-bar-edge,
 .irs-slider {
-    background: url(../img/sprite-skin-nice.png) repeat-x;
+    background: url(img/sprite-skin-nice.png) repeat-x;
 }
 
 .irs {