Drag and drop file attachments into Zoho CRM

I'd love to be able to drag and drop files to Zoho CRM. Single file drag and drop would be great, multiple files simultaneously would be even better. Gmail lets you do it easily, so presumably the programming know-how exists somewhere already. The current method of clicking on "Desktop" under the "Attachments" header and then navigating to the file is slow and tedious, and if I have to attach multiple documents, it isn't even worth doing.