web-apps/vendor/bootstrap/less/_dropdown.less

// The dropdown wrapper (`<div>`)
.dropup,
.dropright,
.dropdown,
.dropleft {
	position: relative;
}

.dropdown-toggle {
	white-space: nowrap;

	// Generate the caret automatically
	#caret();
}

// The dropdown menu
.dropdown-menu {
	position: absolute;
	top: 100%;
	left: 0;
	z-index: @zindex-dropdown;
	display: none; // none by default, but block on "open" of the menu
	float: left;
	min-width: @dropdown-min-width;
	padding: @dropdown-padding-y 0;
	margin: @dropdown-spacer 0 0; // override default ul
	#font-size(@dropdown-font-size);
	color: @dropdown-color;
	text-align: left; // Ensures proper alignment if parent has it changed (e.g., modal footer)
	list-style: none;
	background-color: @dropdown-bg;
	background-clip: padding-box;
	border: @dropdown-border-width solid @dropdown-border-color;
	#border-radius(@dropdown-border-radius);
	#box-shadow(@dropdown-box-shadow);
}

//@each $breakpoint in map-keys($grid-breakpoints) {
//  @include media-breakpoint-up($breakpoint) {
//    $infix: breakpoint-infix($breakpoint, $grid-breakpoints);
//
//    .dropdown-menu#{$infix}-left {
//      right: auto;
//      left: 0;
//    }
//
//    .dropdown-menu#{$infix}-right {
//      right: 0;
//      left: auto;
//    }
//  }
//}
each(map-keys(@grid-breakpoints), #(@breakpoint) {
	#media-breakpoint-up(@breakpoint, {
		@infix: breakpoint-infix(@breakpoint, @grid-breakpoints);

		.dropdown-menu@{infix}-left {
			right: auto;
			left: 0;
		}

		.dropdown-menu@{infix}-right {
			right: 0;
			left: auto;
		}
	});
});

// Allow for dropdowns to go bottom up (aka, dropup-menu)
// Just add .dropup after the standard .dropdown class and you're set.
.dropup {
	.dropdown-menu {
		top: auto;
		bottom: 100%;
		margin-top: 0;
		margin-bottom: @dropdown-spacer;
	}

	.dropdown-toggle {
		#caret(up);
	}
}

.dropright {
	.dropdown-menu {
		top: 0;
		right: auto;
		left: 100%;
		margin-top: 0;
		margin-left: @dropdown-spacer;
	}

	.dropdown-toggle {
		#caret(right);
		&::after {
			vertical-align: 0;
		}
	}
}

.dropleft {
	.dropdown-menu {
		top: 0;
		right: 100%;
		left: auto;
		margin-top: 0;
		margin-right: @dropdown-spacer;
	}

	.dropdown-toggle {
		#caret(left);
		&::before {
			vertical-align: 0;
		}
	}
}

// When enabled Popper.js, reset basic dropdown position
.dropdown-menu {
	&[x-placement^="top"],
	&[x-placement^="right"],
	&[x-placement^="bottom"],
	&[x-placement^="left"] {
		right: auto;
		bottom: auto;
	}
}

// Dividers (basically an `<hr>`) within the dropdown
.dropdown-divider {
	#nav-divider(@dropdown-divider-bg, @dropdown-divider-margin-y, true);
}

// Links, buttons, and more within the dropdown menu
//
// `<button>`-specific styles are denoted with `// For <button>s`
.dropdown-item {
	display: block;
	width: 100%; // For `<button>`s
	padding: @dropdown-item-padding-y @dropdown-item-padding-x;
	clear: both;
	font-weight: @font-weight-normal;
	color: @dropdown-link-color;
	text-align: inherit; // For `<button>`s
	white-space: nowrap; // prevent links from randomly breaking onto new lines
	background-color: transparent; // For `<button>`s
	border: 0; // For `<button>`s

	// Prevent dropdown overflow if there's no padding
	// See https://github.com/twbs/bootstrap/pull/27703
	& when (@dropdown-padding-y = 0) {
		&:first-child {
			#border-top-radius(@dropdown-inner-border-radius);
		}

		&:last-child {
			#border-bottom-radius(@dropdown-inner-border-radius);
		}
	}

	#hover-focus({
		color: @dropdown-link-hover-color;
		text-decoration: none;
		#gradient-bg(@dropdown-link-hover-bg);
	});

	&.active,
	&:active {
		color: @dropdown-link-active-color;
		text-decoration: none;
		#gradient-bg(@dropdown-link-active-bg);
	}

	&.disabled,
	&:disabled {
		color: @dropdown-link-disabled-color;
		pointer-events: none;
		background-color: transparent;
		// Remove CSS gradients if they're enabled
		& when (@enable-gradients) {
			background-image: none;
		}
	}
}

.dropdown-menu.show {
	display: block;
}

// Dropdown section headers
.dropdown-header {
	display: block;
	padding: @dropdown-padding-y @dropdown-item-padding-x;
	margin-bottom: 0; // for use with heading elements
	#font-size(@font-size-sm);
	color: @dropdown-header-color;
	white-space: nowrap; // as with > li > a
}

// Dropdown text
.dropdown-item-text {
	display: block;
	padding: @dropdown-item-padding-y @dropdown-item-padding-x;
	color: @dropdown-link-color;
}