如何使用“class”而不是“id”来使用多个浮动帮助对话？

I need to use multiple floating help dialog boxes in a page. I have tried it by using 'display:block' and 'display:none' and used ID in javascript. I cannot use classes since I have multiple of them on the same page and if I use classes then all of them will be displayed/hide at the same time. However, as the number of help items are increasing in the page, I have to go back to the javascript and add more lines ...I need to use multiple floating help dialog box