CSS implementation to php app

I'm looking for application designer, who can implement new CSS / html to the php-mysql based application. Means I'm trying to give a new outlook to pre-designed application with mobile friendly css. There are 2-3 apps which needed to be integrated with this application as free / paid module. The first application is online based complete business management, in which users will register and can login later. The users will have access of free tools and paid tools or can upgrade later. Admin [our client] will have access of the users and complete business management using the app. If customization will reflect error then you have to solve them also.. as I shall give you application fully tested even with installer, in case get any error.. will send the necessary information/ codes / documentation. This is only CSS masking project, no extra coding required. But you need to be an expert in php / mysql and html css as well. Please bid within the budget.