使用themeroller css时jquery对话框的问题

The demos for the jquery ui dialog all use the "flora" theme. I wanted a customized theme, so I used the themeroller to generate a css file. When I used it, everything seemed to be working fine, but later I found that I can't control any input element contained in the dialog (i.e, can't type into a text field, can't check checkboxes). Further investigation revealed that this happens if I set the dialog attribute "modal" to true. This doesn't happen when I use the flora theme. for the jquery ui dialog all use the