menu.css

/*!
 * jQuery UI Menu 1.13.3
 * https://jqueryui.com
 *
 * Copyright OpenJS Foundation and other contributors
 * Released under the MIT license.
 * https://jquery.org/license
 *
 * https://api.jqueryui.com/menu/#theming
 */
.ui-menu {
	list-style: none;
	padding: 0;
	margin: 0;
	display: block;
	outline: 0;
}
.ui-menu .ui-menu {
	position: absolute;
}
.ui-menu .ui-menu-item {
	margin: 0;
	cursor: pointer;
	/* support: IE10, see #8844 */
	list-style-image: url("data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7");
}
.ui-menu .ui-menu-item-wrapper {
	position: relative;
	padding: 3px 1em 3px .4em;
}
.ui-menu .ui-menu-divider {
	margin: 5px 0;
	height: 0;
	font-size: 0;
	line-height: 0;
	border-width: 1px 0 0 0;
}
.ui-menu .ui-state-focus,
.ui-menu .ui-state-active {
	margin: -1px;
}

/* icon support */
.ui-menu-icons {
	position: relative;
}
.ui-menu-icons .ui-menu-item-wrapper {
	padding-left: 2em;
}

/* left-aligned */
.ui-menu .ui-icon {
	position: absolute;
	top: 0;
	bottom: 0;
	left: .2em;
	margin: auto 0;
}

/* right-aligned */
.ui-menu .ui-menu-icon {
	left: auto;
	right: 0;
}

File

core/assets/vendor/jquery.ui/themes/base/menu.css

/*!
 * jQuery UI Menu 1.13.3
 * https://jqueryui.com
 *
 * Copyright OpenJS Foundation and other contributors
 * Released under the MIT license.
 * https://jquery.org/license
 *
 * https://api.jqueryui.com/menu/#theming
 */
.ui-menu {
	list-style: none;
	padding: 0;
	margin: 0;
	display: block;
	outline: 0;
}
.ui-menu .ui-menu {
	position: absolute;
}
.ui-menu .ui-menu-item {
	margin: 0;
	cursor: pointer;
	/* support: IE10, see #8844 */
	list-style-image: url("data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7");
}
.ui-menu .ui-menu-item-wrapper {
	position: relative;
	padding: 3px 1em 3px .4em;
}
.ui-menu .ui-menu-divider {
	margin: 5px 0;
	height: 0;
	font-size: 0;
	line-height: 0;
	border-width: 1px 0 0 0;
}
.ui-menu .ui-state-focus,
.ui-menu .ui-state-active {
	margin: -1px;
}

/* icon support */
.ui-menu-icons {
	position: relative;
}
.ui-menu-icons .ui-menu-item-wrapper {
	padding-left: 2em;
}

/* left-aligned */
.ui-menu .ui-icon {
	position: absolute;
	top: 0;
	bottom: 0;
	left: .2em;
	margin: auto 0;
}

/* right-aligned */
.ui-menu .ui-menu-icon {
	left: auto;
	right: 0;
}