/* =========================================================
   TIẾNG NGA A1 — HỌC TƯƠNG TÁC
   Token hệ thống thiết kế:
   - Màu: lấy cảm hứng từ men sứ/sơn mài Việt (đỏ trầm, vàng lúa)
     hòa với sắc lạnh của mùa đông Nga (trắng sương, xanh than).
   - Chữ: Literata (tiêu đề tiếng Việt) + Inter (nội dung, chữ Nga)
     + JetBrains Mono (phiên âm, để căn đều ký tự).
   - Dấu ấn riêng: viền "chỉ thêu" đứt nét quanh thẻ flashcard,
     nút audio hình con dấu tròn, lưới 100 ô ("ruộng bậc thang")
     cho bảng tiến độ.
   ========================================================= */

:root {
	--tna-bg: #F1F4F3;
	--tna-card: #FFFFFF;
	--tna-ink: #202B36;
	--tna-ink-soft: #57626C;
	--tna-primary: #AF2E35;      /* đỏ sơn mài */
	--tna-primary-dark: #8C2229;
	--tna-primary-light: #D98087; /* đỏ sơn mài nhạt — dùng cho hover icon, tinh tế hơn */
	--tna-secondary: #D79A2C;    /* vàng lúa */
	--tna-success: #4C7A5B;      /* xanh bạch dương */
	--tna-success-dark: #3A5F47;
	--tna-fail: #A85560;
	--tna-border: #D8DEDB;
	--tna-radius: 14px;
	--tna-shadow: 0 4px 18px rgba(32, 43, 54, 0.08);
}

.tna-app {
	font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
	color: var(--tna-ink);
	max-width: 640px;
	margin: 28px auto;
	box-sizing: border-box;
}

/* [read] chèn tự do trong câu văn không cần bố cục khối (max-width/margin)
   như .tna-app — chỉ cần kế thừa biến màu từ :root và font chữ cơ bản. */
.tna-read-inline {
	font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
	color: var(--tna-ink);
}

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

.tna-app h3, .tna-app h4 {
	font-family: 'Literata', Georgia, serif;
	font-weight: 700;
	color: var(--tna-ink);
}

/* ---------- Hộp thông báo dùng chung ---------- */
.tna-box {
	background: var(--tna-card);
	border: 1px solid var(--tna-border);
	border-radius: var(--tna-radius);
	padding: 16px 18px;
	margin-bottom: 16px;
	font-size: 15px;
	line-height: 1.55;
}
.tna-login-notice {
	background: #FBF1E7;
	border-color: #EAD2A8;
	color: #6B4A1C;
}
.tna-explain { background: #F5F1FB; border-color: #DCD1EF; }
.tna-newwords { background: #EEF6F0; border-color: #CFE4D5; }

/* ---------- Icon SVG nội tuyến dùng thay cho emoji/Dashicons ---------- */
/* ---------- Icon SVG nội tuyến dùng thay cho emoji/Dashicons ----------
   LƯU Ý: KHÔNG scope theo .tna-app — icon cần hiển thị được ở mọi nơi,
   kể cả khi chèn tự do trong bài viết thường qua shortcode [read] (nằm
   ngoài phạm vi .tna-app). Đây chính là nguyên nhân icon từng "biến mất"
   trong bài viết trước khi sửa (chỉ .tna-app .tna-icon mới có
   display:inline-block, còn ngoài .tna-app thì không). */
.tna-icon {
	display: inline-block;
	vertical-align: middle;
	flex-shrink: 0;
}
.tna-audio-btn .tna-icon { width: 18px; height: 18px; }
.tna-btn .tna-icon { width: 16px; height: 16px; margin-right: 2px; vertical-align: -3px; }

/* ---------- Nút bấm dùng chung ---------- */
.tna-btn {
	font-family: 'Inter', sans-serif;
	font-weight: 600;
	font-size: 15px;
	padding: 12px 20px;
	border-radius: 10px;
	border: none;
	cursor: pointer;
	transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s ease;
}
.tna-btn:active { transform: translateY(1px) scale(0.99); }
.tna-btn:focus-visible {
	outline: 3px solid #7FA8D9;
	outline-offset: 2px;
}
.tna-btn-success { background: var(--tna-success); color: #fff; }
.tna-btn-success:hover { background: var(--tna-success-dark); }
.tna-btn-fail { background: #F4E6E7; color: var(--tna-fail); }
.tna-btn-fail:hover { background: #EFD7D9; }
.tna-btn-secondary { background: #E8EBEA; color: var(--tna-ink); }
.tna-btn-secondary:hover { background: #DEE2E0; }
.tna-btn[disabled] { opacity: 0.45; cursor: not-allowed; }

/* Nút loa phát âm — tối giản: không viền, không nền, hover chỉ nhạt màu đi */
.tna-audio-btn {
	width: 40px;
	height: 40px;
	min-width: 40px;
	border-radius: 50%;
	border: none;
	background: #fff;
	color: var(--tna-primary);
	font-size: 16px;
	cursor: pointer;
	display: inline-flex;
	align-items: center;
	justify-content: center;
	transition: color 0.15s ease, transform 0.1s ease;
}
.tna-audio-btn:hover,
.tna-audio-btn:active,
.tna-audio-btn:focus { background: #fff; color: var(--tna-primary-light); }

.tna-audio-btn:focus-visible {
	outline: 2px solid var(--tna-primary-light);
	outline-offset: 2px;
}

/* =========================================================
   FLASHCARD
   ========================================================= */
.tna-flashcard-header { margin-bottom: 14px; }
.tna-progress-bar {
	height: 6px;
	background: #E1E6E4;
	border-radius: 999px;
	overflow: hidden;
}
.tna-progress-fill {
	height: 100%;
	background: linear-gradient(90deg, var(--tna-secondary), var(--tna-primary));
	transition: width 0.3s ease;
}
.tna-flashcard-counter {
	text-align: right;
	font-size: 13px;
	color: var(--tna-ink-soft);
	margin-top: 6px;
	font-family: 'JetBrains Mono', monospace;
}

.tna-flashcard-stage { perspective: 1400px; margin-bottom: 18px; }

.tna-flashcard {
	position: relative;
	min-height: 280px;
	cursor: pointer;
}
.tna-flashcard-inner {
	position: relative;
	width: 100%;
	height: 100%;
	min-height: 280px;
	transition: transform 0.5s cubic-bezier(0.2, 0.7, 0.3, 1);
	transform-style: preserve-3d;
}
.tna-flashcard.is-flipped .tna-flashcard-inner {
	transform: rotateY(180deg);
}
.tna-flashcard-face {
	position: absolute;
	inset: 0;
	backface-visibility: hidden;
	border-radius: 18px;
	background: var(--tna-card);
	box-shadow: var(--tna-shadow);
	padding: 28px 24px;
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: center;
	text-align: center;
	/* dấu ấn riêng: viền "chỉ thêu" đứt nét */
	outline: 2px dashed #E3B9A4;
	outline-offset: -10px;
}
.tna-flashcard-back {
	transform: rotateY(180deg);
	outline-color: #B9D2C0;
}
.tna-card-russian {
	font-size: 34px;
	font-weight: 600;
	margin: 12px 0 6px;
	line-height: 1.25;
}
.tna-card-phonetic {
	font-family: 'JetBrains Mono', monospace;
	font-size: 16px;
	color: var(--tna-ink-soft);
}
.tna-flip-hint {
	position: absolute;
	bottom: 16px;
	font-size: 12px;
	color: #97A19B;
	letter-spacing: 0.03em;
}
.tna-card-meaning {
	font-family: 'Literata', serif;
	font-size: 26px;
	font-weight: 700;
	color: var(--tna-primary-dark);
	margin-bottom: 14px;
}
.tna-card-example-ru { font-size: 15px; margin-bottom: 4px; }
.tna-card-example-vi { font-size: 14px; color: var(--tna-ink-soft); margin-bottom: 12px; }
.tna-card-mnemonic {
	display: flex;
	align-items: flex-start;
	gap: 8px;
	font-size: 13px;
	color: #8A6A2E;
	background: #FBF1E0;
	border-radius: 8px;
	padding: 8px 12px;
	text-align: left;
}
.tna-card-mnemonic .tna-icon { color: #C99A3E; margin-top: 1px; }
.tna-flashcard-front .tna-audio-btn,
.tna-flashcard-back .tna-audio-btn { position: absolute; top: 16px; right: 16px; }

.tna-flashcard-controls {
	display: flex;
	gap: 12px;
}
.tna-flashcard-controls .tna-btn { flex: 1; }

.tna-flashcard-done {
	text-align: center;
	padding: 32px 16px;
}
.tna-done-title { font-family: 'Literata', serif; font-size: 22px; font-weight: 700; }
.tna-done-desc { color: var(--tna-ink-soft); margin-bottom: 18px; }

/* =========================================================
   QUIZ
   ========================================================= */
.tna-quiz-title { margin-bottom: 4px; }
.tna-quiz-progress {
	font-family: 'JetBrains Mono', monospace;
	font-size: 13px;
	color: var(--tna-ink-soft);
	margin-bottom: 14px;
}
.tna-quiz-question {
	background: var(--tna-card);
	border-radius: var(--tna-radius);
	box-shadow: var(--tna-shadow);
	padding: 22px 20px;
	margin-bottom: 16px;
}
.tna-quiz-question-text {
	font-size: 18px;
	font-weight: 600;
	margin-bottom: 16px;
}
.tna-quiz-option {
	display: flex;
	align-items: center;
	gap: 10px;
	padding: 12px 14px;
	border: 2px solid var(--tna-border);
	border-radius: 10px;
	margin-bottom: 10px;
	cursor: pointer;
	transition: border-color 0.12s ease, background 0.12s ease;
}
.tna-quiz-option:hover { border-color: var(--tna-secondary); }
.tna-quiz-option.is-selected { border-color: var(--tna-primary); background: #FBF0EF; }
.tna-quiz-option input { accent-color: var(--tna-primary); }
.tna-quiz-nav { display: flex; gap: 12px; }
.tna-quiz-nav .tna-btn { flex: 1; }

.tna-quiz-result { text-align: center; padding: 20px; }
.tna-quiz-score {
	font-family: 'Literata', serif;
	font-size: 40px;
	font-weight: 700;
	color: var(--tna-primary);
}
.tna-quiz-score-label { color: var(--tna-ink-soft); margin-bottom: 18px; }
.tna-quiz-review-item {
	text-align: left;
	padding: 10px 14px;
	border-radius: 8px;
	margin-bottom: 8px;
	font-size: 14px;
}
.tna-quiz-review-item.is-correct { background: #EAF3EC; }
.tna-quiz-review-item.is-wrong { background: #F7EAEA; }

/* =========================================================
   DASHBOARD — LỘ TRÌNH 100 NGÀY
   ========================================================= */
.tna-dashboard-summary {
	display: grid;
	grid-template-columns: repeat(4, 1fr);
	gap: 10px;
	margin-bottom: 22px;
}
.tna-stat-card {
	background: var(--tna-card);
	border-radius: 12px;
	box-shadow: var(--tna-shadow);
	padding: 14px 8px;
	text-align: center;
}
.tna-stat-number {
	display: block;
	font-family: 'Literata', serif;
	font-size: 26px;
	font-weight: 700;
	color: var(--tna-primary);
}
.tna-stat-label {
	display: block;
	font-size: 11px;
	color: var(--tna-ink-soft);
	margin-top: 2px;
}

.tna-roadmap-grid {
	display: grid;
	grid-template-columns: repeat(10, 1fr);
	gap: 6px;
}
.tna-day-cell {
	aspect-ratio: 1;
	border-radius: 6px;
	border: none;
	background: #E4E9E6;
	color: var(--tna-ink-soft);
	font-family: 'JetBrains Mono', monospace;
	font-size: 11px;
	cursor: pointer;
	display: flex;
	align-items: center;
	justify-content: center;
	transition: transform 0.1s ease;
}
.tna-day-cell:hover { transform: scale(1.12); z-index: 2; position: relative; }
.tna-day-cell:focus-visible { outline: 2px solid #7FA8D9; outline-offset: 1px; }
.tna-day-cell.is-done {
	background: var(--tna-success);
	color: #fff;
}

.tna-day-detail {
	position: fixed;
	inset: auto 16px 16px 16px;
	max-width: 560px;
	margin: 0 auto;
	background: var(--tna-card);
	border-radius: 16px;
	box-shadow: 0 10px 40px rgba(0,0,0,0.2);
	padding: 22px;
	z-index: 100;
}
.tna-day-detail-close {
	position: absolute;
	top: 12px;
	right: 14px;
	background: none;
	border: none;
	font-size: 22px;
	cursor: pointer;
	color: var(--tna-ink-soft);
}
.tna-day-detail-stage {
	font-size: 12px;
	text-transform: uppercase;
	letter-spacing: 0.05em;
	color: var(--tna-secondary);
	font-weight: 700;
}
.tna-day-detail-content { color: var(--tna-ink-soft); line-height: 1.6; }
.tna-day-detail-check {
	display: flex;
	align-items: center;
	gap: 8px;
	margin-top: 14px;
	font-weight: 600;
	cursor: pointer;
}
.tna-day-detail-check input { width: 18px; height: 18px; accent-color: var(--tna-success); }

/* =========================================================
   HỘI THOẠI
   ========================================================= */
.tna-hoithoai-line {
	display: flex;
	align-items: flex-start;
	gap: 12px;
	padding: 10px 0;
	border-bottom: 1px dashed var(--tna-border);
}
.tna-hoithoai-line:last-child { border-bottom: none; }
.tna-hoithoai-ru { font-size: 16px; font-weight: 600; }
.tna-hoithoai-vi { font-size: 14px; color: var(--tna-ink-soft); margin-top: 2px; }

/* =========================================================
   SHORTCODE [read] — ICON LOA CHÈN TỰ DO TRONG BÀI VIẾT
   ========================================================= */
.tna-read-inline {
	display: inline-flex;
	align-items: center;
	gap: 4px;
	vertical-align: middle;
}
.tna-read-text { font-weight: 600; }
.tna-audio-btn-inline {
	width: 30px;
	height: 30px;
	min-width: 30px;
}
.tna-audio-btn-inline .tna-icon { width: 16px; height: 16px; }

/* =========================================================
   BỘ ĐỌC BÀI VIẾT (TTS CHO POST THƯỜNG)
   ========================================================= */
.tna-doc-reader {
	margin: 0 0 20px;
	max-width: none;
}
.tna-reader-toggle { display: inline-flex; align-items: center; gap: 6px; }
.tna-reader-controls {
	display: flex;
	align-items: center;
	gap: 10px;
	flex-wrap: wrap;
	background: var(--tna-card);
	border: 1px solid var(--tna-border);
	border-radius: 12px;
	padding: 10px 14px;
}
.tna-reader-speed {
	border: 1px solid var(--tna-border);
	border-radius: 8px;
	padding: 6px 10px;
	font-family: 'Inter', sans-serif;
	font-size: 13px;
}
.tna-reader-status {
	font-size: 13px;
	color: var(--tna-ink-soft);
	font-family: 'JetBrains Mono', monospace;
}

/* =========================================================
   LANDING PAGE: DANH SÁCH TỪ VỰNG / HỘI THOẠI / QUIZ
   ========================================================= */
.tna-filter-bar {
	display: flex;
	flex-wrap: wrap;
	gap: 8px;
	align-items: center;
	margin-bottom: 16px;
}
.tna-filter-search {
	flex: 1;
	min-width: 200px;
	padding: 10px 14px;
	border: 1px solid var(--tna-border);
	border-radius: 10px;
	font-family: 'Inter', sans-serif;
	font-size: 14px;
}
.tna-filter-select {
	padding: 10px 12px;
	border: 1px solid var(--tna-border);
	border-radius: 10px;
	font-family: 'Inter', sans-serif;
	font-size: 14px;
	background: #fff;
}
.tna-filter-clear {
	font-size: 13px;
	color: var(--tna-ink-soft);
	text-decoration: underline;
	white-space: nowrap;
}
.tna-content-card { position: relative; }
.tna-card-badge {
	position: absolute;
	top: 10px;
	right: 10px;
	font-size: 11px;
	font-weight: 700;
	padding: 3px 9px;
	border-radius: 999px;
	font-family: 'JetBrains Mono', monospace;
}
.tna-card-badge-new { background: #E4E9E6; color: var(--tna-ink-soft); }
.tna-card-badge-learning { background: #FBF1E0; color: #8A6A2E; }
.tna-card-badge-mastered { background: #E1EFE4; color: var(--tna-success-dark); }

.tna-content-grid {
	display: grid;
	grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
	gap: 14px;
}
.tna-content-card {
	display: flex;
	flex-direction: column;
	gap: 6px;
	background: var(--tna-card);
	border: 1px solid var(--tna-border);
	border-radius: 14px;
	padding: 18px 16px;
	text-decoration: none;
	color: var(--tna-ink);
	box-shadow: var(--tna-shadow);
	transition: transform 0.12s ease, border-color 0.12s ease;
}
.tna-content-card:hover {
	transform: translateY(-2px);
	border-color: var(--tna-secondary);
}
.tna-content-card-title {
	font-size: 18px;
	font-weight: 600;
}
.tna-content-card-sub {
	font-size: 13px;
	color: var(--tna-ink-soft);
	font-family: 'JetBrains Mono', monospace;
}
.tna-pagination {
	display: flex;
	justify-content: center;
	gap: 6px;
	margin-top: 24px;
	flex-wrap: wrap;
}
.tna-pagination .page-numbers {
	display: inline-flex;
	align-items: center;
	justify-content: center;
	min-width: 36px;
	height: 36px;
	padding: 0 10px;
	border-radius: 8px;
	background: var(--tna-card);
	border: 1px solid var(--tna-border);
	color: var(--tna-ink);
	text-decoration: none;
	font-size: 14px;
}
.tna-pagination .page-numbers.current {
	background: var(--tna-primary);
	border-color: var(--tna-primary);
	color: #fff;
	font-weight: 700;
}
.tna-pagination .page-numbers:hover:not(.current) { border-color: var(--tna-secondary); }

/* =========================================================
   DANH MỤC CHỦ ĐỀ
   ========================================================= */
.tna-chude-grid {
	display: grid;
	grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
	gap: 14px;
}
.tna-chude-card {
	display: flex;
	flex-direction: column;
	align-items: flex-start;
	gap: 8px;
	background: var(--tna-card);
	border: 1px solid var(--tna-border);
	border-radius: 14px;
	padding: 18px 16px;
	text-decoration: none;
	color: var(--tna-ink);
	box-shadow: var(--tna-shadow);
	transition: transform 0.12s ease, border-color 0.12s ease;
}
.tna-chude-card:hover {
	transform: translateY(-2px);
	border-color: var(--tna-secondary);
}
.tna-chude-card-icon {
	width: 40px;
	height: 40px;
	border-radius: 10px;
	background: #F3E7E4;
	color: var(--tna-primary);
	display: flex;
	align-items: center;
	justify-content: center;
}
.tna-chude-card-name {
	font-family: 'Literata', Georgia, serif;
	font-weight: 700;
	font-size: 16px;
}
.tna-chude-card-meta {
	font-size: 12px;
	color: var(--tna-ink-soft);
	font-family: 'JetBrains Mono', monospace;
}

/* =========================================================
   BOX ĐIỀU HƯỚNG: CHỦ ĐỀ + NỘI DUNG LIÊN QUAN
   ========================================================= */
.tna-related-nav {
	background: var(--tna-card, #fff);
	border: 1px solid var(--tna-border, #D8DEDB);
	border-radius: 14px;
	padding: 18px 20px;
	margin-top: 20px;
}
.tna-related-topics {
	display: flex;
	flex-wrap: wrap;
	gap: 8px;
	margin-bottom: 14px;
}
.tna-topic-pill {
	display: inline-block;
	padding: 6px 14px;
	border-radius: 999px;
	background: #F3E7E4;
	color: #8C2229;
	font-size: 13px;
	font-weight: 600;
	text-decoration: none;
}
.tna-topic-pill:hover { background: #EAD5D1; }
.tna-related-section { margin-top: 14px; }
.tna-related-heading {
	font-family: 'Literata', Georgia, serif;
	font-size: 14px;
	text-transform: uppercase;
	letter-spacing: 0.04em;
	color: var(--tna-ink-soft, #57626C);
	margin: 0 0 8px;
}
.tna-related-heading-small {
	font-size: 12px;
	text-transform: uppercase;
	letter-spacing: 0.04em;
	color: var(--tna-ink-soft, #57626C);
	margin-bottom: 6px;
}
.tna-related-empty-note {
	font-size: 14px;
	color: var(--tna-ink-soft, #57626C);
	margin: 0 0 14px;
}
.tna-topic-pill-outline {
	background: transparent;
	border: 1px solid var(--tna-border, #D8DEDB);
	color: var(--tna-ink-soft, #57626C);
}
.tna-topic-pill-outline:hover { background: #F3E7E4; color: #8C2229; border-color: transparent; }
.tna-related-nav .tna-related-section:first-of-type { margin-top: 4px; }
.tna-related-list {
	list-style: none;
	margin: 0;
	padding: 0;
	display: flex;
	flex-wrap: wrap;
	gap: 8px 16px;
}
.tna-related-list li { font-size: 14px; }
.tna-related-list a {
	color: var(--tna-primary, #AF2E35);
	text-decoration: none;
	border-bottom: 1px dashed currentColor;
}
.tna-related-list a:hover { border-bottom-style: solid; }

/* =========================================================
   RESPONSIVE
   ========================================================= */
@media (max-width: 480px) {
	.tna-card-russian { font-size: 26px; }
	.tna-dashboard-summary { grid-template-columns: repeat(2, 1fr); }
	.tna-roadmap-grid { grid-template-columns: repeat(7, 1fr); }
	.tna-flashcard-controls { flex-direction: column; }
}

/* Tôn trọng người dùng tắt hiệu ứng chuyển động */
@media (prefers-reduced-motion: reduce) {
	.tna-flashcard-inner, .tna-btn, .tna-day-cell { transition: none !important; }
}