Dropdown Login Form using pure CSS

 I know that adding a dropdown login form can be done with sophistication using bootstrap. This was on top of my list when it comes to this particular task but given the circumstances, I opted to use CSS/Javascript because I encountered several errors with Bootstrap and it such a very inconvenience to modify my existing codes just to make it work.

The errors I encountered when I used bootstrap were as follows:

• The left sidebar was deformed after I declared bootstrap 
• The float chat button window user avatar disappeared
•  The padding of all elements changed

 

I mean all display elements got affected just by declaring bootstrap. So I used pure CSS/Javascript instead so that I dont have to modify my existing code.