/**
 * GFMR Table of Contents (TOC) Styles
 *
 * Sticky sidebar navigation for Markdown headings
 * with scroll tracking and responsive design
 *
 * @package MarkdownRendererForGitHub
 * @since 1.12.0
 */

/* ==========================================================================
   CSS Variables
   ========================================================================== */

:root {

	/* TOC Layout */
	--gfmr-toc-width: 250px;
	--gfmr-toc-gap: 24px;
	--gfmr-toc-top: 24px;

	/* TOC Colors (Light Theme) */
	--gfmr-toc-bg: var(--gfmr-bg-subtle);
	--gfmr-toc-border-color: var(--gfmr-border-default);
	--gfmr-toc-link-color: var(--gfmr-text-secondary);
	--gfmr-toc-link-hover: var(--gfmr-text-primary);
	--gfmr-toc-link-active: var(--gfmr-color-primary);
	--gfmr-toc-active-bg: var(--gfmr-bg-muted);
	--gfmr-toc-active-border: var(--gfmr-color-primary);

	/* TOC Typography */
	--gfmr-toc-font-size: 14px;
	--gfmr-toc-line-height: 1.5;
	--gfmr-toc-indent: 1rem;

	/* TOC Spacing */
	--gfmr-toc-padding: 16px;
	--gfmr-toc-item-padding-y: 6px;
	--gfmr-toc-item-padding-x: 12px;

	/* TOC Animation */
	--gfmr-toc-transition: 0.25s ease;
}

/* Dark Theme Variables */
[data-gfmr-theme="dark"] :root,
[data-gfmr-theme="system"]:where(.gfmr-theme-dark) :root {
	--gfmr-toc-bg: var(--gfmr-bg-subtle-dark);
	--gfmr-toc-border-color: var(--gfmr-border-default-dark);
	--gfmr-toc-link-color: var(--gfmr-text-secondary-dark);
	--gfmr-toc-link-hover: var(--gfmr-text-primary-dark);
	--gfmr-toc-link-active: var(--gfmr-color-primary-dark);
	--gfmr-toc-active-bg: var(--gfmr-bg-muted-dark);
	--gfmr-toc-active-border: var(--gfmr-color-primary-dark);
}

@media (prefers-color-scheme: dark) {

	:root:not([data-gfmr-theme="light"]) {
		--gfmr-toc-bg: var(--gfmr-bg-subtle-dark);
		--gfmr-toc-border-color: var(--gfmr-border-default-dark);
		--gfmr-toc-link-color: var(--gfmr-text-secondary-dark);
		--gfmr-toc-link-hover: var(--gfmr-text-primary-dark);
		--gfmr-toc-link-active: var(--gfmr-color-primary-dark);
		--gfmr-toc-active-bg: var(--gfmr-bg-muted-dark);
		--gfmr-toc-active-border: var(--gfmr-color-primary-dark);
	}
}

/* ==========================================================================
   TOC Layout Wrapper (Flexbox)
   ========================================================================== */

.gfmr-toc-layout {
	display: flex;
	gap: var(--gfmr-toc-gap);
	align-items: flex-start;
}

/* Content area should take remaining space */
.gfmr-toc-layout > .gfmr-markdown-rendered,
.gfmr-toc-layout > .gfmr-render {
	flex: 1;
	min-width: 0; /* Prevent flex item overflow */
}

/* ==========================================================================
   TOC Sidebar Container
   ========================================================================== */

.gfmr-toc-sidebar {
	position: sticky;
	top: var(--gfmr-toc-top);
	width: var(--gfmr-toc-width);
	flex-shrink: 0; /* Prevent sidebar from shrinking */
	max-height: calc(100vh - var(--gfmr-toc-top) - var(--gfmr-toc-top));
	overflow-y: auto;
	overflow-x: hidden;
	background-color: var(--gfmr-toc-bg);
	border: 1px solid var(--gfmr-toc-border-color);
	border-radius: 6px;
	padding: var(--gfmr-toc-padding);
	z-index: 1020;
	transition: opacity var(--gfmr-toc-transition);
}

/* Use flex order instead of float */
.gfmr-toc-sidebar--right {
	order: 1; /* Right side in flex layout */
}

.gfmr-toc-sidebar--left {
	order: -1; /* Left side in flex layout */
}

/* Scrollbar Styling */
.gfmr-toc-sidebar::-webkit-scrollbar {
	width: 6px;
}

.gfmr-toc-sidebar::-webkit-scrollbar-track {
	background: transparent;
}

.gfmr-toc-sidebar::-webkit-scrollbar-thumb {
	background-color: var(--gfmr-border-default);
	border-radius: 3px;
}

.gfmr-toc-sidebar::-webkit-scrollbar-thumb:hover {
	background-color: var(--gfmr-text-secondary);
}

/* ==========================================================================
   TOC Title
   ========================================================================== */

.gfmr-toc-title {
	font-size: 16px;
	font-weight: 600;
	color: var(--gfmr-text-primary);
	margin: 0 0 12px 0;
	padding-bottom: 8px;
	border-bottom: 1px solid var(--gfmr-border-default);
}

/* ==========================================================================
   TOC List
   ========================================================================== */

.gfmr-toc-list {
	list-style: none;
	margin: 0;
	padding: 0;
}

.gfmr-toc-item {
	position: relative;
	margin: 0;
	padding: 0;
}

.gfmr-toc-link {
	display: block;
	padding: var(--gfmr-toc-item-padding-y) var(--gfmr-toc-item-padding-x);
	font-size: var(--gfmr-toc-font-size);
	line-height: var(--gfmr-toc-line-height);
	color: var(--gfmr-toc-link-color);
	text-decoration: none;
	border-left: 2px solid transparent;
	transition: all var(--gfmr-toc-transition);
}

.gfmr-toc-link:hover {
	color: var(--gfmr-toc-link-hover);
	background-color: var(--gfmr-toc-active-bg);
}

.gfmr-toc-link:focus {
	outline: 2px solid var(--gfmr-color-primary);
	outline-offset: 2px;
}

/* Active State */
.gfmr-toc-item--active > .gfmr-toc-link {
	color: var(--gfmr-toc-link-active);
	background-color: var(--gfmr-toc-active-bg);
	border-left-color: var(--gfmr-toc-active-border);
	font-weight: 600;
}

/* ==========================================================================
   TOC Heading Levels (Hierarchical Indentation)
   ========================================================================== */

.gfmr-toc-link[data-level="1"] {
	padding-left: calc(var(--gfmr-toc-item-padding-x));
}

.gfmr-toc-link[data-level="2"] {
	padding-left: calc(var(--gfmr-toc-item-padding-x) + var(--gfmr-toc-indent) * 1);
}

.gfmr-toc-link[data-level="3"] {
	padding-left: calc(var(--gfmr-toc-item-padding-x) + var(--gfmr-toc-indent) * 2);
}

.gfmr-toc-link[data-level="4"] {
	padding-left: calc(var(--gfmr-toc-item-padding-x) + var(--gfmr-toc-indent) * 3);
}

.gfmr-toc-link[data-level="5"] {
	padding-left: calc(var(--gfmr-toc-item-padding-x) + var(--gfmr-toc-indent) * 4);
}

.gfmr-toc-link[data-level="6"] {
	padding-left: calc(var(--gfmr-toc-item-padding-x) + var(--gfmr-toc-indent) * 5);
}

/* ==========================================================================
   Responsive Design
   ========================================================================== */

/* Mobile: Hide TOC on small screens */
@media (max-width: 767px) {

	.gfmr-toc-sidebar.gfmr-toc-mobile-hidden {
		display: none;
	}
}

/* Tablet: Stack layout vertically */
@media (min-width: 768px) and (max-width: 1023px) {

	.gfmr-toc-layout {
		flex-direction: column;
	}

	.gfmr-toc-sidebar {
		position: relative;
		top: 0;
		width: 100%;
		max-height: none;
		order: -1; /* TOC above content on narrow screens */
		--gfmr-toc-padding: 12px;
		--gfmr-toc-font-size: 13px;
	}
}

/* Desktop: Side-by-side layout */
@media (min-width: 1024px) {

	.gfmr-toc-layout {
		flex-direction: row;
	}

	.gfmr-toc-sidebar {
		--gfmr-toc-width: 250px;
	}
}

/* ==========================================================================
   Print Styles
   ========================================================================== */

@media print {

	.gfmr-toc-sidebar {
		display: none;
	}
}

/* ==========================================================================
   Accessibility
   ========================================================================== */

/* High Contrast Mode Support */
@media (prefers-contrast: high) {

	.gfmr-toc-sidebar {
		border-width: 2px;
	}

	.gfmr-toc-item--active > .gfmr-toc-link {
		border-left-width: 4px;
	}
}

/* Reduced Motion Support */
@media (prefers-reduced-motion: reduce) {

	.gfmr-toc-link,
	.gfmr-toc-sidebar {
		transition: none;
	}
}

/* Focus Visible (Keyboard Navigation) */
.gfmr-toc-link:focus-visible {
	outline: 2px solid var(--gfmr-color-primary);
	outline-offset: 2px;
}

.gfmr-toc-link:focus:not(:focus-visible) {
	outline: none;
}