Hi,
Looks like you have accidentally removed the icons inside the
/templates/flexible_lightmart/images/Flexible/ folder. You should put them back there.
I just created a ZIP for you.
1- Download this ZIP file:
demo.flexiblewebdesign.com/lightmart/icons.zip
2- UNZIP it, and you will get around 100 icons.
3- Upload those icons to this path:
cucuttemp-cp145.webjoomla.es/templates/flexible_lightmart/images/Flexible/
So, this URL below won't return 404-Not Found:
cucuttemp-cp145.webjoomla.es/templates/flexible_lightmart/images/Flexible/plus_minus.png
Regards.