带滚动切换效果的弹出登录框，jQuery仿QQ登陆框效果，在窗口的右上角有一个小坠球效果，点击坠球可切换登录界面，打开网页的时候，这个登录框默认是不会出现的，需要点击文字“点我弹出登录框”才会弹出来，右上角有关闭按钮，不需要的时候可随时关闭它。-With scrolling pop-up login box transition effects, jQuery effects of imitation QQ login box in the upper right corner of the window there is a little fall ball effect, dropping the ball when clicking to switch the login screen, open a web page, the login box will not appear by default , need to click on the text　point I pop up login box　will pop up, upper right corner close button when not needed can always turn it off.