/*
 * 
 * Structural layout.
 */

:root {
	--layout-sidebar-width: 280px;
	--layout-main-max-width: 1200px;
}

.app-layout {
	display: flex;
	flex-direction: column;
	min-height: 100vh;
	background: var(--color-bg);
}

.mobile-topbar {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: var(--space-3);
	padding: var(--space-3) var(--space-4);
	border-bottom: 1px solid var(--color-border);
	background: color-mix(in srgb, var(--color-surface) 92%, var(--color-surface-alt));
	position: sticky;
	top: 0;
	z-index: calc(var(--z-sidebar) + 1);
}

.mobile-topbar-left,
.mobile-topbar-right {
	display: inline-flex;
	align-items: center;
	gap: var(--space-2);
}

.mobile-topbar-title {
	font-size: var(--text-base);
	line-height: var(--leading-tight);
	white-space: nowrap;
	overflow: hidden;
	text-overflow: ellipsis;
	max-width: min(56vw, 22rem);
}

.app-sidebar {
	position: fixed;
	top: 0;
	left: 0;
	bottom: 0;
	z-index: var(--z-sidebar);
	width: min(88vw, var(--layout-sidebar-width));
	background: var(--color-surface-alt);
	border-right: 1px solid var(--color-border);
	transform: translateX(-100%);
	visibility: hidden;
	transition: transform 240ms ease, visibility 240ms ease;
}

.sidebar-backdrop {
	position: fixed;
	inset: 0;
	z-index: calc(var(--z-sidebar) - 1);
	background: color-mix(in srgb, var(--color-overlay) 92%, transparent);
	opacity: 0;
	visibility: hidden;
	pointer-events: none;
	transition: opacity 220ms ease, visibility 220ms ease;
}

.app-sidebar-inner {
	display: flex;
	flex-direction: column;
	gap: var(--space-4);
	min-height: 100%;
	padding: var(--space-5);
	overflow-y: auto;
}

.app-main {
	flex: 1 1 auto;
	min-width: 0;
	position: relative;
}

.app-main-inner {
	width: 100%;
	max-width: var(--layout-main-max-width);
	margin: 0 auto;
	padding: var(--space-5);
}

.view-header {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: var(--space-4);
	margin-bottom: var(--space-5);
	padding-bottom: var(--space-4);
	border-bottom: 1px solid var(--color-border);
}

.view-body {
	display: flex;
	flex-direction: column;
	gap: var(--space-4);
}

.sidebar-header {
	display: grid;
	gap: var(--space-3);
	padding-bottom: var(--space-4);
	margin-bottom: var(--space-2);
	border-bottom: 1px solid var(--color-border);
}

.sidebar-header-row {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: var(--space-3);
}

.sidebar-header-actions {
	display: flex;
	align-items: center;
	gap: var(--space-2);
}

.sidebar-close-btn {
	display: inline-flex;
}

.app-title {
	font-size: var(--text-xl);
	line-height: var(--leading-tight);
}

.welcome-panel {
	background: var(--color-surface);
	border: 1px solid var(--color-border);
	border-radius: var(--radius-xl);
	box-shadow: var(--shadow-sm);
	padding: var(--space-6);
	display: grid;
	gap: var(--space-3);
}

.section-title {
	font-size: var(--text-xl);
	line-height: var(--leading-tight);
}

.section-copy {
	font-size: var(--text-base);
	line-height: var(--leading-loose);
}

.deck-header-copy {
	display: grid;
	gap: var(--space-1);
}

.deck-title {
	font-size: var(--text-xl);
	line-height: var(--leading-tight);
}

.deck-meta {
	font-family: var(--font-ui);
	font-size: var(--text-sm);
	color: var(--color-text-muted);
}

.deck-header-actions {
	display: flex;
	align-items: center;
	gap: var(--space-3);
}

.deck-toolbar {
	display: flex;
	align-items: end;
	justify-content: space-between;
	gap: var(--space-4);
	padding: var(--space-4);
	border: 1px solid var(--color-border);
	border-radius: var(--radius-lg);
	background: var(--color-surface);
	box-shadow: var(--shadow-sm);
	margin-bottom: var(--space-5);
}

.search-field {
	display: grid;
	gap: var(--space-2);
	flex: 1 1 auto;
}

.search-label {
	font-family: var(--font-ui);
	font-size: var(--text-sm);
	font-weight: var(--weight-medium);
	color: var(--color-text-secondary);
}

.view-study {
	display: flex;
	align-items: center;
	justify-content: center;
	min-height: 100vh;
	padding: var(--space-6);
	background: var(--color-bg);
}

.study-container {
	width: 100%;
	max-width: var(--layout-main-max-width);
	display: flex;
	flex-direction: column;
	align-items: center;
	gap: var(--space-5);
}

.study-controls {
	width: 100%;
	display: flex;
	align-items: center;
	justify-content: center;
	gap: var(--space-3);
}

@media (min-width: 640px) {
	.app-sidebar {
		width: min(72vw, var(--layout-sidebar-width));
	}
}

@media (min-width: 768px) {
	.mobile-topbar,
	.sidebar-backdrop,
	.sidebar-close-btn {
		display: none;
	}

	.app-layout {
		flex-direction: row;
	}

	.app-sidebar {
		position: sticky;
		top: 0;
		z-index: var(--z-sidebar);
		flex: 0 0 var(--layout-sidebar-width);
		width: var(--layout-sidebar-width);
		height: 100vh;
		border-bottom: 0;
		border-right: 1px solid var(--color-border);
		transform: none;
		visibility: visible;
	}

	.app-layout .app-sidebar,
	.app-layout.is-sidebar-open .app-sidebar,
	.app-layout.is-sidebar-closed .app-sidebar {
		transform: none;
		visibility: visible;
	}

	.app-main-inner,
	.view-study {
		padding: var(--space-6);
	}
}

@media (max-width: 767px) {
	.app-layout.is-sidebar-open .app-sidebar {
		transform: translateX(0);
		visibility: visible;
	}

	.app-layout.is-sidebar-closed .app-sidebar {
		transform: translateX(-100%);
		visibility: hidden;
	}

	.app-layout.is-sidebar-open .sidebar-backdrop {
		opacity: 1;
		visibility: visible;
		pointer-events: auto;
	}

	.app-main-inner {
		padding: max(var(--space-4), env(safe-area-inset-top)) var(--space-4) max(var(--space-5), env(safe-area-inset-bottom));
	}

	.app-sidebar-inner {
		padding-top: max(var(--space-5), env(safe-area-inset-top));
		padding-bottom: max(var(--space-5), env(safe-area-inset-bottom));
	}

	.view-header,
	.deck-toolbar {
		flex-direction: column;
		align-items: stretch;
	}

	.deck-header-actions {
		width: 100%;
		justify-content: flex-start;
		flex-wrap: wrap;
	}

	.welcome-panel {
		padding: var(--space-5);
	}
}

@media (min-width: 1024px) {
	:root {
		--layout-sidebar-width: 300px;
	}
}

@media (min-width: 1280px) {
	:root {
		--layout-main-max-width: 1400px;
	}

	.app-main-inner,
	.view-study {
		padding: var(--space-8);
	}
}