Want to roll back to earlier default theme

Hi

My site is Fadfinity.biz

I tried to modify (increase width size) the post area and now everything got messed. I feel really sorry for that. Again was too lazy to create child theme. I need help to roll back to the earlier default theme. I tried to delete the Aqueduct folder from wordpress theme folder on server and did fresh installation. But it shows the same earlier mess. Please help me to reset it to earlier default theme setting.