Form problem : calendar pop up overriden by an autocomplete field Drupal 7. I use a bootstrap theme with some customized css.
I have a node/edit form with a date field with calendar popup widget and an entityreference field with autocomplete widget.

When I click on the date field, a part of the calendar is missing : it is overriden by the autocomplete field.(see picture below)

If I change the widget for the entityreference field and choose select widget, the calendar is OK.

With the original bootstrap theme (without customized css), the calendar is OK.

Is there something I can change in CSS to prevent the calendar to be overridden by the autocomplete field ? (should I change the date css ? or the autocomplete css ?, which setting ?)
Try:

input{
  position: relative !important;
  z-index: 0 !important;
}


You can change the "input" selector to meet your needs and try this without "!important" also.