in templates/ydotm/bootstrap3.js [928:968]
Modal.prototype.backdrop = function (callback) {
var animate = this.$element.hasClass('fade') ? 'fade' : ''
if (this.isShown && this.options.backdrop) {
var doAnimate = $.support.transition && animate
this.$backdrop = $('<div class="modal-backdrop ' + animate + '" />')
.appendTo(document.body)
this.$element.on('click.dismiss.bs.modal', $.proxy(function (e) {
if (e.target !== e.currentTarget) return
this.options.backdrop == 'static'
? this.$element[0].focus.call(this.$element[0])
: this.hide.call(this)
}, this))
if (doAnimate) this.$backdrop[0].offsetWidth // force reflow
this.$backdrop.addClass('in')
if (!callback) return
doAnimate ?
this.$backdrop
.one($.support.transition.end, callback)
.emulateTransitionEnd(150) :
callback()
} else if (!this.isShown && this.$backdrop) {
this.$backdrop.removeClass('in')
$.support.transition && this.$element.hasClass('fade') ?
this.$backdrop
.one($.support.transition.end, callback)
.emulateTransitionEnd(150) :
callback()
} else if (callback) {
callback()
}
}