Codeigniter：我如何防止改变网站风格？

I am able to run the website properly on localhost, however when I uploaded to the live server, and fill the form and insert the value in one of the specific textbox ( promo code) , my website style changes and messes the whole look. I cannot select or send the form and have to refresh the page. This was not doing on the localhost, it is only doing on live site. Can you please advice?

I have attached the screenshot for you to understand what it does actually.

Thanks in advance.

(when i insert the value in the textbox) enter image description here

(when i loose focus from the textbox) enter image description here

(And in the localhost) enter image description here