Bootstrap modal window is grayed out [closed]

It’s because .navbar-fixed-top has a z-index of 1030 while the modal backdrop has a z-index of 1040, causing the modal to overlay the navbar.

To fix this, just adjust the .modal-backdrop z-index value to be lower than 1030 – e.g.

.modal-backdrop {
    z-index: 1020;
}