/* ==========================================================================
   CNL — Reset & typography
   ========================================================================== */

*, *::before, *::after { box-sizing: border-box; }

html {
	-webkit-text-size-adjust: 100%;
	scroll-behavior: smooth;
	scroll-padding-top: calc(var(--cnl-header-h) + 16px);
}

body {
	margin: 0;
	font-family: var(--cnl-font);
	font-size: var(--cnl-fs-base);
	line-height: 1.65;
	color: var(--cnl-ink);
	background: var(--cnl-surface);
	-webkit-font-smoothing: antialiased;
	-moz-osx-font-smoothing: grayscale;
	overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
	margin: 0 0 .5em;
	font-weight: 800;
	line-height: 1.22;
	letter-spacing: -.02em;
	color: var(--cnl-ink);
	text-wrap: balance;
}

h1 { font-size: var(--cnl-fs-3xl); }
h2 { font-size: var(--cnl-fs-2xl); }
h3 { font-size: var(--cnl-fs-xl); }
h4 { font-size: var(--cnl-fs-lg); }

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

a {
	color: var(--cnl-primary);
	text-decoration: none;
	transition: color var(--cnl-t);
}
a:hover { color: var(--cnl-primary-700); }

img, svg, video, canvas, audio, iframe { display: block; max-width: 100%; }
img { height: auto; }

ul, ol { margin: 0 0 1em; padding-left: 1.25em; }
li { margin-bottom: .35em; }

button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }

hr {
	border: 0;
	height: 1px;
	background: var(--cnl-line);
	margin: var(--cnl-gap-lg) 0;
}

blockquote {
	margin: 1.5em 0;
	padding: 1em 1.25em;
	border-left: 4px solid var(--cnl-primary);
	background: var(--cnl-primary-50);
	border-radius: 0 var(--cnl-r) var(--cnl-r) 0;
	color: var(--cnl-ink-2);
	font-style: normal;
}

code, kbd, pre {
	font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
	font-size: .9em;
}
code {
	background: var(--cnl-surface-2);
	padding: .15em .4em;
	border-radius: 6px;
}
pre {
	background: var(--cnl-ink);
	color: #F1F4F9;
	padding: 1.1em 1.25em;
	border-radius: var(--cnl-r);
	overflow-x: auto;
}
pre code { background: none; padding: 0; color: inherit; }

table {
	width: 100%;
	border-collapse: collapse;
	margin-bottom: 1.5em;
	font-size: var(--cnl-fs-base);
}
th, td {
	padding: .75em .9em;
	text-align: left;
	border-bottom: 1px solid var(--cnl-line);
}
th { font-weight: 700; color: var(--cnl-ink); }

/* --- Chữ Hán: luôn dùng font riêng và cỡ lớn hơn để dễ nhìn nét --- */
.cnl-hanzi,
.hanzi {
	font-family: var(--cnl-font-hanzi);
	font-weight: 500;
	letter-spacing: .02em;
	line-height: 1.35;
}

.cnl-pinyin {
	font-style: italic;
	color: var(--cnl-primary);
	font-weight: 500;
	letter-spacing: .01em;
}

/* --- Tiện ích --- */
.cnl-container {
	width: 100%;
	max-width: var(--cnl-container);
	margin-inline: auto;
	padding-inline: clamp(16px, 4vw, 32px);
}
.cnl-container--narrow { max-width: var(--cnl-container-narrow); }

.cnl-section { padding-block: var(--cnl-section); }
.cnl-section--tight { padding-block: calc(var(--cnl-section) * .6); }
.cnl-section--alt { background: var(--cnl-surface-2); }

.screen-reader-text {
	position: absolute !important;
	width: 1px; height: 1px;
	margin: -1px; padding: 0;
	overflow: hidden;
	clip: rect(0 0 0 0);
	clip-path: inset(50%);
	white-space: nowrap;
	border: 0;
}

.cnl-skip-link {
	position: absolute;
	top: -60px; left: 16px;
	z-index: var(--cnl-z-modal);
	padding: 12px 20px;
	background: var(--cnl-primary);
	color: #fff;
	border-radius: 0 0 var(--cnl-r) var(--cnl-r);
	font-weight: 600;
	transition: top var(--cnl-t);
}
.cnl-skip-link:focus { top: 0; color: #fff; }

/* --- Focus rõ ràng cho bàn phím --- */
:focus-visible {
	outline: 3px solid var(--cnl-primary);
	outline-offset: 2px;
	border-radius: 4px;
}

::selection {
	background: var(--cnl-primary-100);
	color: var(--cnl-primary-700);
}

/* --- Thanh cuộn mảnh --- */
.cnl-scroll-x {
	overflow-x: auto;
	scrollbar-width: thin;
	-webkit-overflow-scrolling: touch;
}
.cnl-scroll-x::-webkit-scrollbar { height: 6px; }
.cnl-scroll-x::-webkit-scrollbar-thumb {
	background: var(--cnl-line);
	border-radius: var(--cnl-r-pill);
}

/* --- Tôn trọng thiết lập giảm chuyển động --- */
@media (prefers-reduced-motion: reduce) {
	html { scroll-behavior: auto; }
	*, *::before, *::after {
		animation-duration: .01ms !important;
		animation-iteration-count: 1 !important;
		transition-duration: .01ms !important;
	}
}

/* --- In ấn (chứng chỉ, đề thi) --- */
@media print {
	.cnl-header, .cnl-footer, .cnl-tabbar, .cnl-btn, .cnl-crumbs { display: none !important; }
	body { background: #fff; }
	.cnl-card { box-shadow: none; border: 1px solid #ddd; }
}