/* ============================================================
 * XEGHEP Help Center — Styles
 * PL-2.1 | Phase 2
 *
 * Loaded ONLY on help center pages (/trung-tam-huong-dan/*).
 * Depends on: tokens.css, components.css
 *
 * Architecture: Mobile-First, Dark Mode Compatible
 * ============================================================ */

/* ── CSS Custom Properties (inherit from tokens.css) ── */
:root {
	--hc-bg: #f8fafc;
	--hc-surface: #ffffff;
	--hc-border: #e2e8f0;
	--hc-text: #1e293b;
	--hc-text-secondary: #64748b;
	--hc-primary: #2563eb;
	--hc-primary-hover: #1d4ed8;
	--hc-accent: #eff6ff;
	--hc-success: #059669;
	--hc-warning: #d97706;
	--hc-error: #dc2626;
	--hc-radius: 12px;
	--hc-shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
	--hc-shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.04);
	--hc-shadow-lg: 0 4px 16px rgba(0,0,0,0.08);
	--hc-transition: 150ms ease;
}

/* ── Dark Mode ── */
@media (prefers-color-scheme: dark) {
	:root {
		--hc-bg: #0f172a;
		--hc-surface: #1e293b;
		--hc-border: #334155;
		--hc-text: #f1f5f9;
		--hc-text-secondary: #94a3b8;
		--hc-accent: #1e3a5f;
	}
}

/* ============================================================
   LAYOUT
   ============================================================ */
.hc-main {
	background: var(--hc-bg);
	min-height: 100vh;
	padding-bottom: calc(80px + 2rem); /* Bottom Nav offset */
}

.hc-container {
	max-width: 960px;
	margin: 0 auto;
	padding: 0 1rem;
}

.hc-section {
	padding: 2.5rem 0;
}

.hc-section-title {
	font-size: 1.25rem;
	font-weight: 700;
	color: var(--hc-text);
	margin: 0 0 1.25rem 0;
	padding: 0;
	letter-spacing: -0.01em;
}

/* ============================================================
   HERO SECTION
   ============================================================ */
.hc-hero {
	background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 50%, #1e40af 100%);
	color: #ffffff;
	padding: 3rem 0 2.5rem;
	text-align: center;
}

@media (prefers-color-scheme: dark) {
	.hc-hero {
		background: linear-gradient(135deg, #1e3a5f 0%, #1e40af 50%, #1e3a8a 100%);
	}
}

.hc-hero-content {
	max-width: 640px;
	margin: 0 auto;
}

.hc-hero-title {
	font-size: 1.75rem;
	font-weight: 800;
	line-height: 1.2;
	margin: 0 0 0.75rem 0;
	letter-spacing: -0.02em;
	color: #ffffff;
}

.hc-hero-subtitle {
	font-size: 0.9375rem;
	line-height: 1.5;
	opacity: 0.9;
	margin: 0 0 1.5rem 0;
	padding: 0 0.5rem;
}

/* ── Search Box ── */
.hc-search {
	position: relative;
	max-width: 520px;
	margin: 0 auto;
}

.hc-search-form {
	position: relative;
	display: flex;
	align-items: center;
	background: rgba(255,255,255,0.2);
	backdrop-filter: blur(10px);
	border: 1px solid rgba(255,255,255,0.25);
	border-radius: var(--hc-radius);
	padding: 0 0.5rem;
	transition: background var(--hc-transition), border var(--hc-transition);
}

.hc-search-form:focus-within {
	background: rgba(255,255,255,0.3);
	border-color: rgba(255,255,255,0.5);
}

.hc-search-icon {
	flex-shrink: 0;
	color: rgba(255,255,255,0.7);
	margin-right: 0.5rem;
}

.hc-search-input {
	flex: 1;
	border: none;
	background: transparent;
	color: #ffffff;
	font-size: 0.9375rem;
	padding: 0.75rem 0;
	outline: none;
	font-family: inherit;
	width: 100%;
}

.hc-search-input::placeholder {
	color: rgba(255,255,255,0.6);
}

.hc-search-clear {
	flex-shrink: 0;
	border: none;
	background: transparent;
	color: rgba(255,255,255,0.7);
	cursor: pointer;
	padding: 0.375rem;
	margin-left: 0.25rem;
	border-radius: 6px;
	display: flex;
	align-items: center;
	justify-content: center;
	transition: color var(--hc-transition);
}

.hc-search-clear:hover {
	color: #ffffff;
}

/* Search Results Dropdown */
.hc-search-results {
	position: absolute;
	top: calc(100% + 0.5rem);
	left: 0;
	right: 0;
	background: var(--hc-surface);
	border: 1px solid var(--hc-border);
	border-radius: var(--hc-radius);
	box-shadow: var(--hc-shadow-lg);
	max-height: 320px;
	overflow-y: auto;
	z-index: 100;
	text-align: left;
}

.hc-search-result-item {
	display: block;
	padding: 0.75rem 1rem;
	color: var(--hc-text);
	text-decoration: none;
	font-size: 0.875rem;
	line-height: 1.4;
	border-bottom: 1px solid var(--hc-border);
	transition: background var(--hc-transition);
	cursor: pointer;
}

.hc-search-result-item:last-child {
	border-bottom: none;
}

.hc-search-result-item:hover,
.hc-search-result-item:focus {
	background: var(--hc-accent);
}

.hc-search-result-title {
	font-weight: 600;
	display: block;
}

.hc-search-result-cat {
	font-size: 0.75rem;
	color: var(--hc-text-secondary);
	display: block;
	margin-top: 0.125rem;
}

.hc-search-empty {
	padding: 1.5rem 1rem;
	text-align: center;
	color: var(--hc-text-secondary);
	font-size: 0.875rem;
}

/* ============================================================
   CATEGORY CARDS
   ============================================================ */
.hc-categories-grid {
	display: grid;
	grid-template-columns: 1fr;
	gap: 0.75rem;
}

@media (min-width: 640px) {
	.hc-categories-grid {
		grid-template-columns: repeat(2, 1fr);
	}
}

@media (min-width: 960px) {
	.hc-categories-grid {
		grid-template-columns: repeat(3, 1fr);
	}
}

.hc-category-card {
	display: flex;
	align-items: center;
	gap: 0.875rem;
	background: var(--hc-surface);
	border: 1px solid var(--hc-border);
	border-radius: var(--hc-radius);
	padding: 1rem 1.125rem;
	text-decoration: none;
	color: var(--hc-text);
	transition: box-shadow var(--hc-transition), transform var(--hc-transition), border-color var(--hc-transition);
	cursor: pointer;
	position: relative;
	overflow: hidden;
}

.hc-category-card:hover {
	border-color: var(--hc-primary);
	box-shadow: var(--hc-shadow);
	transform: translateY(-1px);
}

.hc-category-card:active {
	transform: translateY(0);
}

.hc-category-icon {
	flex-shrink: 0;
	width: 48px;
	height: 48px;
	border-radius: 12px;
	background: rgba(37, 99, 235, 0.08);
	display: flex;
	align-items: center;
	justify-content: center;
	transition: background var(--hc-transition);
}

.hc-category-card:hover .hc-category-icon {
	background: rgba(37, 99, 235, 0.12);
}

.hc-category-text {
	flex: 1;
	min-width: 0;
}

.hc-category-title {
	font-size: 0.9375rem;
	font-weight: 600;
	color: var(--hc-text);
	margin: 0 0 0.125rem 0;
	line-height: 1.3;
}

.hc-category-desc {
	font-size: 0.8125rem;
	color: var(--hc-text-secondary);
	margin: 0;
	line-height: 1.4;
}

.hc-category-arrow {
	flex-shrink: 0;
	color: var(--hc-text-secondary);
	transition: transform var(--hc-transition), color var(--hc-transition);
}

.hc-category-card:hover .hc-category-arrow {
	transform: translateX(2px);
	color: var(--hc-primary);
}

/* ============================================================
   ARTICLE CARDS (Featured / New / Popular)
   ============================================================ */
.hc-articles-grid {
	display: grid;
	grid-template-columns: 1fr;
	gap: 0.625rem;
}

@media (min-width: 640px) {
	.hc-articles-grid {
		grid-template-columns: repeat(2, 1fr);
	}
}

.hc-article-card {
	display: flex;
	align-items: flex-start;
	gap: 0.75rem;
	background: var(--hc-surface);
	border: 1px solid var(--hc-border);
	border-radius: var(--hc-radius);
	padding: 0.875rem 1rem;
	text-decoration: none;
	color: var(--hc-text);
	transition: box-shadow var(--hc-transition), border-color var(--hc-transition);
}

.hc-article-card:hover {
	border-color: var(--hc-primary);
	box-shadow: var(--hc-shadow-sm);
}

.hc-article-card-icon {
	flex-shrink: 0;
	width: 36px;
	height: 36px;
	border-radius: 8px;
	background: rgba(37, 99, 235, 0.06);
	display: flex;
	align-items: center;
	justify-content: center;
	color: var(--hc-primary);
	margin-top: 2px;
}

.hc-article-card-body {
	flex: 1;
	min-width: 0;
}

.hc-article-card-title {
	font-size: 0.875rem;
	font-weight: 600;
	color: var(--hc-text);
	margin: 0 0 0.25rem 0;
	line-height: 1.4;
}

.hc-article-card-time {
	font-size: 0.75rem;
	color: var(--hc-text-secondary);
}

/* ============================================================
   QUICK ACTIONS
   ============================================================ */
.hc-quick-actions-grid {
	display: grid;
	grid-template-columns: repeat(2, 1fr);
	gap: 0.75rem;
}

@media (min-width: 640px) {
	.hc-quick-actions-grid {
		grid-template-columns: repeat(4, 1fr);
	}
}

.hc-quick-action {
	display: flex;
	flex-direction: column;
	align-items: center;
	gap: 0.5rem;
	background: var(--hc-surface);
	border: 1px solid var(--hc-border);
	border-radius: var(--hc-radius);
	padding: 1.25rem 0.75rem;
	text-decoration: none;
	color: var(--hc-text);
	font-size: 0.8125rem;
	font-weight: 500;
	text-align: center;
	transition: border-color var(--hc-transition), box-shadow var(--hc-transition), transform var(--hc-transition);
}

.hc-quick-action:hover {
	border-color: var(--hc-primary);
	box-shadow: var(--hc-shadow-sm);
	transform: translateY(-1px);
}

.hc-quick-action svg {
	color: var(--hc-primary);
}

/* ============================================================
   FAQ ACCORDION
   ============================================================ */
.hc-faq-list {
	display: flex;
	flex-direction: column;
	gap: 0.5rem;
}

.hc-faq-item {
	background: var(--hc-surface);
	border: 1px solid var(--hc-border);
	border-radius: var(--hc-radius);
	overflow: hidden;
	transition: border-color var(--hc-transition);
}

.hc-faq-item[open] {
	border-color: var(--hc-primary);
}

.hc-faq-question {
	display: flex;
	align-items: center;
	justify-content: space-between;
	padding: 1rem 1.125rem;
	font-size: 0.9375rem;
	font-weight: 600;
	color: var(--hc-text);
	cursor: pointer;
	user-select: none;
	list-style: none; /* Remove default marker */
	gap: 0.75rem;
}

.hc-faq-question::-webkit-details-marker {
	display: none;
}

.hc-faq-question::marker {
	display: none;
}

.hc-faq-chevron {
	flex-shrink: 0;
	color: var(--hc-text-secondary);
	transition: transform var(--hc-transition);
}

.hc-faq-item[open] .hc-faq-chevron {
	transform: rotate(180deg);
}

.hc-faq-answer {
	padding: 0 1.125rem 1.125rem;
	font-size: 0.875rem;
	line-height: 1.6;
	color: var(--hc-text-secondary);
}

.hc-faq-answer p {
	margin: 0;
}

/* ============================================================
   SUPPORT BOX (Reusable)
   ============================================================ */
.hc-support-box {
	background: var(--hc-surface);
	border: 1px solid var(--hc-border);
	border-radius: var(--hc-radius);
	padding: 1.5rem;
	text-align: center;
}

.hc-support-box-header {
	display: flex;
	align-items: center;
	justify-content: center;
	gap: 0.5rem;
	margin-bottom: 0.75rem;
	color: var(--hc-text);
}

.hc-support-box-title {
	font-size: 1.125rem;
	font-weight: 700;
	margin: 0;
	color: var(--hc-text);
}

.hc-support-box-desc {
	font-size: 0.875rem;
	color: var(--hc-text-secondary);
	margin: 0 0 1.25rem 0;
	line-height: 1.5;
}

.hc-support-box-contact {
	display: grid;
	grid-template-columns: 1fr 1fr;
	gap: 0.75rem;
	text-align: left;
	margin-bottom: 1.5rem;
}

@media (max-width: 480px) {
	.hc-support-box-contact {
		grid-template-columns: 1fr;
	}
}

.hc-support-box-row {
	display: flex;
	flex-direction: column;
	gap: 0.125rem;
}

.hc-support-box-label {
	font-size: 0.75rem;
	color: var(--hc-text-secondary);
	text-transform: uppercase;
	letter-spacing: 0.04em;
	font-weight: 500;
}

.hc-support-box-value {
	font-size: 0.9375rem;
	font-weight: 600;
	color: var(--hc-text);
}

.hc-support-box-link {
	font-size: 0.9375rem;
	font-weight: 600;
	color: var(--hc-primary);
	text-decoration: none;
	transition: color var(--hc-transition);
}

.hc-support-box-link:hover {
	color: var(--hc-primary-hover);
	text-decoration: underline;
}

.hc-support-box-cta {
	display: flex;
	flex-wrap: wrap;
	gap: 0.625rem;
	justify-content: center;
}

/* ============================================================
   ARTICLE DETAIL PAGE
   ============================================================ */

/* Breadcrumb */
.hc-breadcrumb {
	display: flex;
	align-items: center;
	flex-wrap: wrap;
	gap: 0.375rem;
	font-size: 0.8125rem;
	color: var(--hc-text-secondary);
	padding: 1rem 0;
	line-height: 1.4;
}

.hc-breadcrumb a {
	color: var(--hc-primary);
	text-decoration: none;
}

.hc-breadcrumb a:hover {
	text-decoration: underline;
}

.hc-breadcrumb-sep {
	color: var(--hc-border);
	user-select: none;
}

/* Article Meta */
.hc-article-meta {
	display: flex;
	align-items: center;
	flex-wrap: wrap;
	gap: 0.75rem;
	font-size: 0.8125rem;
	color: var(--hc-text-secondary);
	margin-bottom: 1.5rem;
}

.hc-article-meta-item {
	display: flex;
	align-items: center;
	gap: 0.25rem;
}

/* Article Title */
.hc-article-title {
	font-size: 1.5rem;
	font-weight: 800;
	color: var(--hc-text);
	margin: 0 0 0.5rem 0;
	line-height: 1.3;
	letter-spacing: -0.01em;
}

/* Table of Contents */
.hc-toc {
	background: var(--hc-surface);
	border: 1px solid var(--hc-border);
	border-radius: var(--hc-radius);
	padding: 1.25rem 1.25rem 1rem;
	margin-bottom: 2rem;
}

.hc-toc-title {
	font-size: 0.9375rem;
	font-weight: 700;
	color: var(--hc-text);
	margin: 0 0 0.75rem 0;
}

.hc-toc-list {
	list-style: none;
	margin: 0;
	padding: 0;
	display: flex;
	flex-direction: column;
	gap: 0.375rem;
}

.hc-toc-list a {
	display: block;
	font-size: 0.875rem;
	color: var(--hc-primary);
	text-decoration: none;
	padding: 0.25rem 0;
	transition: color var(--hc-transition);
	border-left: 2px solid transparent;
	padding-left: 0.75rem;
}

.hc-toc-list a:hover {
	color: var(--hc-primary-hover);
	border-left-color: var(--hc-primary);
}

/* Article Body */
.hc-article-body {
	font-size: 0.9375rem;
	line-height: 1.7;
	color: var(--hc-text);
}

.hc-article-body h2 {
	font-size: 1.25rem;
	font-weight: 700;
	margin: 2rem 0 0.75rem 0;
	color: var(--hc-text);
}

.hc-article-body h3 {
	font-size: 1.0625rem;
	font-weight: 600;
	margin: 1.5rem 0 0.5rem 0;
	color: var(--hc-text);
}

.hc-article-body p {
	margin: 0 0 1rem 0;
}

.hc-article-body ul,
.hc-article-body ol {
	margin: 0 0 1rem 0;
	padding-left: 1.5rem;
}

.hc-article-body li {
	margin-bottom: 0.375rem;
}

.hc-article-body img {
	max-width: 100%;
	border-radius: 8px;
	margin: 1rem 0;
}

/* Tips / Warnings Box */
.hc-tip-box,
.hc-warning-box {
	border-radius: var(--hc-radius);
	padding: 1rem 1.25rem;
	margin: 1.25rem 0;
	font-size: 0.875rem;
	line-height: 1.5;
	display: flex;
	gap: 0.75rem;
}

.hc-tip-box {
	background: rgba(5, 150, 105, 0.06);
	border: 1px solid rgba(5, 150, 105, 0.2);
	color: var(--hc-text);
}

.hc-tip-box svg {
	flex-shrink: 0;
	color: var(--hc-success);
}

.hc-warning-box {
	background: rgba(217, 119, 6, 0.06);
	border: 1px solid rgba(217, 119, 6, 0.2);
	color: var(--hc-text);
}

.hc-warning-box svg {
	flex-shrink: 0;
	color: var(--hc-warning);
}

/* Placeholder for screenshots/video */
.hc-placeholder {
	background: var(--hc-bg);
	border: 2px dashed var(--hc-border);
	border-radius: var(--hc-radius);
	padding: 2rem;
	text-align: center;
	color: var(--hc-text-secondary);
	font-size: 0.8125rem;
	margin: 1.25rem 0;
}

/* Step-by-step */
.hc-steps {
	counter-reset: hc-step;
	list-style: none;
	padding: 0;
	margin: 0;
}

.hc-step {
	position: relative;
	padding-left: 3rem;
	margin-bottom: 1.5rem;
	counter-increment: hc-step;
}

.hc-step::before {
	content: counter(hc-step);
	position: absolute;
	left: 0;
	top: 0;
	width: 2rem;
	height: 2rem;
	background: var(--hc-primary);
	color: #ffffff;
	border-radius: 50%;
	display: flex;
	align-items: center;
	justify-content: center;
	font-size: 0.875rem;
	font-weight: 700;
}

/* Related Articles */
.hc-related {
	margin-top: 2.5rem;
	padding-top: 1.5rem;
	border-top: 1px solid var(--hc-border);
}

.hc-related-title {
	font-size: 1rem;
	font-weight: 700;
	color: var(--hc-text);
	margin: 0 0 1rem 0;
}

.hc-related-list {
	list-style: none;
	margin: 0;
	padding: 0;
	display: flex;
	flex-direction: column;
	gap: 0.5rem;
}

.hc-related-list a {
	font-size: 0.875rem;
	color: var(--hc-primary);
	text-decoration: none;
	transition: color var(--hc-transition);
}

.hc-related-list a:hover {
	color: var(--hc-primary-hover);
	text-decoration: underline;
}

/* ============================================================
   FEEDBACK WIDGET ("Bài viết này có hữu ích không?")
   ============================================================ */
.hc-feedback {
	text-align: center;
	padding: 1.5rem 0;
	margin-top: 2rem;
	border-top: 1px solid var(--hc-border);
}

.hc-feedback-question {
	font-size: 0.9375rem;
	font-weight: 600;
	color: var(--hc-text);
	margin: 0 0 0.75rem 0;
}

.hc-feedback-buttons {
	display: flex;
	gap: 0.75rem;
	justify-content: center;
}

.hc-feedback-btn {
	display: flex;
	align-items: center;
	gap: 0.5rem;
	padding: 0.625rem 1.25rem;
	border: 1px solid var(--hc-border);
	border-radius: 8px;
	background: var(--hc-surface);
	color: var(--hc-text);
	font-size: 0.875rem;
	font-weight: 500;
	cursor: pointer;
	transition: all var(--hc-transition);
	font-family: inherit;
}

.hc-feedback-btn:hover {
	border-color: var(--hc-primary);
	background: var(--hc-accent);
}

.hc-feedback-btn.voted {
	background: var(--hc-primary);
	color: #ffffff;
	border-color: var(--hc-primary);
}

.hc-feedback-thanks {
	font-size: 0.875rem;
	color: var(--hc-success);
	font-weight: 500;
	margin-top: 0.75rem;
}

/* ============================================================
   ARTICLE CTA
   ============================================================ */
.hc-article-cta {
	display: flex;
	flex-wrap: wrap;
	gap: 0.625rem;
	justify-content: center;
	padding: 1.5rem 0;
	border-top: 1px solid var(--hc-border);
	margin-top: 1.5rem;
}

/* ============================================================
   BUTTONS
   ============================================================ */
.hc-btn {
	display: inline-flex;
	align-items: center;
	gap: 0.375rem;
	padding: 0.625rem 1.25rem;
	border-radius: 8px;
	font-size: 0.875rem;
	font-weight: 600;
	text-decoration: none;
	transition: all var(--hc-transition);
	border: 1px solid transparent;
	cursor: pointer;
	font-family: inherit;
	white-space: nowrap;
}

.hc-btn-primary {
	background: var(--hc-primary);
	color: #ffffff;
	border-color: var(--hc-primary);
}

.hc-btn-primary:hover {
	background: var(--hc-primary-hover);
	box-shadow: var(--hc-shadow-sm);
}

.hc-btn-secondary {
	background: var(--hc-surface);
	color: var(--hc-primary);
	border-color: var(--hc-primary);
}

.hc-btn-secondary:hover {
	background: var(--hc-accent);
}

.hc-btn-outline {
	background: transparent;
	color: var(--hc-text-secondary);
	border-color: var(--hc-border);
}

.hc-btn-outline:hover {
	border-color: var(--hc-primary);
	color: var(--hc-primary);
}

/* ============================================================
   CATEGORY PAGE
   ============================================================ */
.hc-category-header {
	background: var(--hc-surface);
	border: 1px solid var(--hc-border);
	border-radius: var(--hc-radius);
	padding: 1.5rem;
	margin-bottom: 1.5rem;
}

.hc-category-header-title {
	font-size: 1.25rem;
	font-weight: 700;
	color: var(--hc-text);
	margin: 0;
}

.hc-category-header-desc {
	font-size: 0.875rem;
	color: var(--hc-text-secondary);
	margin: 0.5rem 0 0 0;
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 480px) {
	.hc-hero {
		padding: 2rem 0 1.75rem;
	}

	.hc-hero-title {
		font-size: 1.375rem;
	}

	.hc-section {
		padding: 1.75rem 0;
	}

	.hc-section-title {
		font-size: 1.125rem;
	}

	.hc-article-title {
		font-size: 1.25rem;
	}
}