/* ============================================================
   gzen Language Learning Site — Main Stylesheet
   ============================================================ */

/* --- Variables --- */
:root {
  --color-jp-primary: #c0392b;
  --color-jp-secondary: #e74c3c;
  --color-jp-light: #fdf2f2;
  --color-jp-accent: #f39c12;

  --color-ru-primary: #1a3a8f;
  --color-ru-secondary: #2980b9;
  --color-ru-light: #f0f4ff;
  --color-ru-accent: #e74c3c;

  --color-bg: #fafafa;
  --color-surface: #ffffff;
  --color-text: #1a1a2e;
  --color-text-muted: #6b7280;
  --color-border: #e5e7eb;
  --color-success: #16a34a;

  --font-sans: 'Noto Sans', 'Noto Sans JP', sans-serif;
  --font-serif-jp: 'Noto Serif JP', serif;
  --font-mono: 'Courier New', monospace;

  --radius: 8px;
  --radius-lg: 16px;
  --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
}

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  font-size: 16px;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; }

/* --- Layout --- */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* --- Site Header --- */
.site-header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 1rem;
}
.logo {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 700;
  font-size: 1.4rem;
  color: var(--color-text);
  text-decoration: none;
}
.logo-jp {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--color-jp-primary), var(--color-jp-secondary));
  color: #fff;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  font-family: var(--font-serif-jp);
}
.logo-text { color: var(--color-text); }
.main-nav {
  display: flex;
  gap: 0.25rem;
}
.main-nav a {
  padding: 0.4rem 0.85rem;
  border-radius: 20px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-muted);
  transition: background 0.2s, color 0.2s;
}
.main-nav a:hover, .main-nav a.active {
  background: var(--color-jp-light);
  color: var(--color-jp-primary);
}
.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.25rem;
}

/* --- Site Footer --- */
.site-footer {
  background: var(--color-text);
  color: #e5e7eb;
  margin-top: 4rem;
  padding: 3rem 0 1.5rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}
.footer-brand .logo-text { color: #fff; }
.footer-brand p {
  margin-top: 0.5rem;
  font-size: 0.9rem;
  color: #9ca3af;
}
.footer-links h4 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #9ca3af;
  margin-bottom: 0.75rem;
}
.footer-links ul { list-style: none; }
.footer-links li { margin-bottom: 0.4rem; }
.footer-links a {
  color: #d1d5db;
  font-size: 0.9rem;
  transition: color 0.2s;
}
.footer-links a:hover { color: #fff; }
.footer-bottom {
  border-top: 1px solid #374151;
  padding-top: 1.25rem;
  text-align: center;
  font-size: 0.85rem;
  color: #6b7280;
}

/* ============================================================
   Homepage
   ============================================================ */
.hero {
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
  color: #fff;
  padding: 5rem 0 4rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '学日ロ語';
  position: absolute;
  font-family: var(--font-serif-jp);
  font-size: 15rem;
  opacity: 0.04;
  top: -2rem;
  right: -2rem;
  pointer-events: none;
  line-height: 1;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 20px;
  padding: 0.35rem 1rem;
  font-size: 0.85rem;
  margin-bottom: 1.5rem;
  color: #e2e8f0;
}
.hero h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1rem;
}
.hero h1 .jp { font-family: var(--font-serif-jp); color: #fca5a5; }
.hero h1 .ru { color: #93c5fd; }
.hero-sub {
  font-size: 1.1rem;
  color: #cbd5e1;
  max-width: 560px;
  margin: 0 auto 2rem;
}
.hero-cta {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.5rem;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s, opacity 0.15s;
  border: 2px solid transparent;
  text-decoration: none;
}
.btn:hover { transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-jp {
  background: var(--color-jp-primary);
  color: #fff;
}
.btn-ru {
  background: var(--color-ru-primary);
  color: #fff;
}
.btn-outline {
  background: transparent;
  border-color: rgba(255,255,255,0.4);
  color: #fff;
}
.btn-outline:hover { background: rgba(255,255,255,0.1); }

/* --- Section Headings --- */
.section-heading {
  text-align: center;
  margin-bottom: 2.5rem;
}
.section-heading h2 {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}
.section-heading p {
  color: var(--color-text-muted);
  max-width: 540px;
  margin: 0 auto;
}

/* --- Today's Lessons Strip --- */
.today-strip {
  padding: 3.5rem 0;
}
.today-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 1rem;
}
.today-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: transform 0.2s, box-shadow 0.2s;
  display: flex;
  flex-direction: column;
}
.today-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}
.today-card-header {
  padding: 1rem 1.25rem 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.today-card-header.jp { background: var(--color-jp-light); border-bottom: 3px solid var(--color-jp-primary); }
.today-card-header.ru { background: var(--color-ru-light); border-bottom: 3px solid var(--color-ru-primary); }
.lang-flag { font-size: 1.5rem; }
.lang-meta { flex: 1; }
.lang-name {
  font-weight: 700;
  font-size: 0.95rem;
  display: block;
}
.lang-level {
  font-size: 0.78rem;
  color: var(--color-text-muted);
}
.day-badge {
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.2rem 0.6rem;
  border-radius: 12px;
  background: #fff;
  box-shadow: var(--shadow);
}
.today-card-body {
  padding: 1.25rem;
  flex: 1;
}
.today-card-body h3 { font-size: 1rem; font-weight: 700; margin-bottom: 0.35rem; }
.today-card-body p { font-size: 0.875rem; color: var(--color-text-muted); margin-bottom: 1rem; }
.today-card-footer { padding: 0 1.25rem 1.25rem; }

/* --- Lesson Calendar Grid --- */
.calendar-section { padding: 3rem 0; }
.language-tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 2rem;
}
.tab-btn {
  padding: 0.5rem 1.25rem;
  border-radius: 20px;
  border: 2px solid var(--color-border);
  background: var(--color-surface);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 600;
  transition: all 0.2s;
}
.tab-btn.active-jp, .tab-btn:hover { border-color: var(--color-jp-primary); color: var(--color-jp-primary); }
.calendar-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 0.75rem;
}
.calendar-day {
  background: var(--color-surface);
  border: 2px solid var(--color-border);
  border-radius: var(--radius);
  padding: 0.85rem 0.75rem;
  text-align: center;
  text-decoration: none;
  color: var(--color-text);
  transition: all 0.2s;
  position: relative;
}
.calendar-day:hover {
  border-color: var(--color-jp-primary);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.calendar-day .day-num {
  display: block;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
  margin-bottom: 0.3rem;
}
.calendar-day .day-kanji {
  display: block;
  font-family: var(--font-serif-jp);
  font-size: 1.5rem;
  line-height: 1.2;
  margin-bottom: 0.2rem;
}
.calendar-day .day-title {
  display: block;
  font-size: 0.72rem;
  color: var(--color-text-muted);
  line-height: 1.3;
}
.calendar-day.jp-card:hover { border-color: var(--color-jp-primary); }
.calendar-day.ru-card:hover { border-color: var(--color-ru-primary); }
.calendar-day.completed { background: #f0fdf4; border-color: var(--color-success); }
.calendar-day.completed::after {
  content: '✓';
  position: absolute;
  top: 4px;
  right: 6px;
  font-size: 0.65rem;
  color: var(--color-success);
  font-weight: 700;
}

/* --- How It Works --- */
.how-it-works { padding: 3.5rem 0; background: var(--color-surface); }
.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1.5rem;
}
.step-card {
  text-align: center;
  padding: 1.5rem;
}
.step-icon {
  font-size: 2.5rem;
  margin-bottom: 0.75rem;
  display: block;
}
.step-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 0.4rem; }
.step-card p { font-size: 0.875rem; color: var(--color-text-muted); }

/* ============================================================
   Lesson / Single Page
   ============================================================ */
.lesson-layout {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 2rem;
  max-width: 1100px;
  margin: 2rem auto;
  padding: 0 1.25rem;
  align-items: start;
}
.lesson-article { min-width: 0; }
.lesson-header {
  margin-bottom: 2rem;
}
.lesson-breadcrumb {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin-bottom: 0.75rem;
}
.lesson-breadcrumb a {
  color: var(--color-jp-primary);
  text-decoration: underline;
}
.lesson-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}
.lang-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.25rem 0.7rem;
  border-radius: 12px;
  font-size: 0.8rem;
  font-weight: 700;
}
.lang-tag.jp { background: var(--color-jp-light); color: var(--color-jp-primary); }
.lang-tag.ru { background: var(--color-ru-light); color: var(--color-ru-primary); }
.level-tag {
  padding: 0.25rem 0.7rem;
  border-radius: 12px;
  font-size: 0.8rem;
  font-weight: 600;
  background: #f3f4f6;
  color: var(--color-text-muted);
}
.lesson-header h1 {
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 0.5rem;
}
.lesson-header .subtitle {
  font-size: 1rem;
  color: var(--color-text-muted);
}

/* --- Lesson Body Prose --- */
.lesson-body {
  font-size: 1.0rem;
  line-height: 1.8;
}
.lesson-body h2 {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2rem 0 0.75rem;
  padding-bottom: 0.35rem;
  border-bottom: 2px solid var(--color-border);
}
.lang-japanese .lesson-body h2 { border-color: var(--color-jp-primary); }
.lang-russian .lesson-body h2 { border-color: var(--color-ru-primary); }
.lesson-body h3 { font-size: 1.1rem; font-weight: 700; margin: 1.5rem 0 0.5rem; }
.lesson-body p { margin-bottom: 1rem; }
.lesson-body ul, .lesson-body ol { padding-left: 1.5rem; margin-bottom: 1rem; }
.lesson-body li { margin-bottom: 0.35rem; }
.lesson-body blockquote {
  border-left: 4px solid var(--color-jp-primary);
  padding: 0.75rem 1.25rem;
  background: var(--color-jp-light);
  margin: 1.25rem 0;
  border-radius: 0 var(--radius) var(--radius) 0;
  font-style: italic;
}
.lang-russian .lesson-body blockquote {
  border-color: var(--color-ru-primary);
  background: var(--color-ru-light);
}
.lesson-body code {
  background: #f3f4f6;
  padding: 0.1em 0.4em;
  border-radius: 4px;
  font-size: 0.9em;
  font-family: var(--font-mono);
}
.lesson-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.25rem 0;
  font-size: 0.93rem;
}
.lesson-body th {
  background: #f3f4f6;
  font-weight: 700;
  padding: 0.6rem 0.9rem;
  text-align: left;
  border: 1px solid var(--color-border);
}
.lang-japanese .lesson-body th { background: var(--color-jp-light); }
.lang-russian .lesson-body th { background: var(--color-ru-light); }
.lesson-body td {
  padding: 0.6rem 0.9rem;
  border: 1px solid var(--color-border);
}
.lesson-body tr:nth-child(even) td { background: #fafafa; }

/* --- Ruby / Furigana --- */
ruby {
  font-family: var(--font-serif-jp);
  font-size: 1.1em;
  line-height: 2.4;
}
ruby rt {
  font-size: 0.45em;
  color: var(--color-jp-primary);
  font-family: var(--font-sans);
  font-weight: 500;
  letter-spacing: 0.03em;
}
.furigana-block {
  display: inline-block;
  background: var(--color-jp-light);
  border-radius: var(--radius);
  padding: 0.5rem 0.75rem;
  margin: 0.5rem 0;
  font-family: var(--font-serif-jp);
  font-size: 1.2rem;
  line-height: 2.5;
}

/* --- Vocab & Grammar Cards --- */
.vocab-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.75rem;
  margin: 1.25rem 0;
}
.vocab-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 0.85rem;
  transition: box-shadow 0.2s;
}
.vocab-card:hover { box-shadow: var(--shadow-md); }
.vocab-card .word {
  font-family: var(--font-serif-jp);
  font-size: 1.4rem;
  display: block;
  margin-bottom: 0.2rem;
}
.vocab-card .reading {
  font-size: 0.8rem;
  color: var(--color-jp-primary);
  display: block;
  margin-bottom: 0.3rem;
}
.vocab-card .meaning {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}
.grammar-box {
  background: linear-gradient(135deg, var(--color-jp-light), #fff8f0);
  border: 1px solid #fde68a;
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  margin: 1.25rem 0;
}
.grammar-box .pattern {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--color-jp-primary);
  margin-bottom: 0.35rem;
  font-family: var(--font-serif-jp);
}
.grammar-box .meaning-en {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  margin-bottom: 0.5rem;
}
.grammar-box .example {
  background: #fff;
  border-radius: 6px;
  padding: 0.6rem 0.85rem;
  margin-top: 0.5rem;
  font-size: 0.9rem;
}
.grammar-box .example .jp-text { font-family: var(--font-serif-jp); display: block; margin-bottom: 0.25rem; }
.grammar-box .example .en-text { font-size: 0.82rem; color: var(--color-text-muted); }

/* Russian grammar box */
.grammar-box.ru {
  background: linear-gradient(135deg, var(--color-ru-light), #f0f7ff);
  border-color: #93c5fd;
}
.grammar-box.ru .pattern { color: var(--color-ru-primary); }

/* --- Practice / Quiz Section --- */
.practice-section {
  background: #f8fafc;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  margin: 2rem 0;
}
.practice-section h2 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 1rem;
  border-bottom: none !important;
}
.quiz-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem;
  margin-bottom: 0.75rem;
}
.quiz-item .question {
  font-weight: 600;
  margin-bottom: 0.5rem;
  font-family: var(--font-serif-jp);
}
.quiz-item .answer {
  font-size: 0.88rem;
  color: var(--color-text-muted);
  display: none;
  margin-top: 0.4rem;
  padding-top: 0.4rem;
  border-top: 1px dashed var(--color-border);
}
.quiz-item.revealed .answer { display: block; }
.reveal-btn {
  font-size: 0.8rem;
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: 20px;
  background: none;
  cursor: pointer;
  color: var(--color-text-muted);
  margin-top: 0.5rem;
  transition: all 0.15s;
}
.reveal-btn:hover { background: var(--color-jp-light); color: var(--color-jp-primary); border-color: var(--color-jp-primary); }

/* --- Sidebar --- */
.lesson-sidebar { position: sticky; top: 80px; }
.sidebar-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-bottom: 1.25rem;
}
.sidebar-card h3 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
  margin-bottom: 0.75rem;
}
.progress-bar-wrap { background: #f3f4f6; border-radius: 10px; height: 8px; margin-bottom: 0.4rem; }
.progress-bar { height: 8px; border-radius: 10px; background: linear-gradient(90deg, var(--color-jp-primary), var(--color-jp-accent)); transition: width 0.4s; }
.progress-label { font-size: 0.78rem; color: var(--color-text-muted); }
.sidebar-nav-list { list-style: none; }
.sidebar-nav-list li { margin-bottom: 0.3rem; }
.sidebar-nav-list a {
  display: block;
  font-size: 0.875rem;
  padding: 0.3rem 0.5rem;
  border-radius: 6px;
  color: var(--color-text-muted);
  transition: all 0.15s;
}
.sidebar-nav-list a:hover, .sidebar-nav-list a.current {
  background: var(--color-jp-light);
  color: var(--color-jp-primary);
  padding-left: 0.9rem;
}
.lang-russian .sidebar-nav-list a:hover,
.lang-russian .sidebar-nav-list a.current {
  background: var(--color-ru-light);
  color: var(--color-ru-primary);
}

/* --- Lesson List Page --- */
.list-hero {
  padding: 3rem 0 2rem;
  text-align: center;
}
.list-hero.jp { background: var(--color-jp-light); }
.list-hero.ru { background: var(--color-ru-light); }
.list-hero h1 { font-size: 2rem; font-weight: 700; margin-bottom: 0.5rem; }
.list-hero p { color: var(--color-text-muted); }
.lesson-list-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
  padding: 2.5rem 0;
}
.lesson-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: transform 0.2s, box-shadow 0.2s;
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
}
.lesson-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); }
.lesson-card-accent {
  height: 4px;
}
.lesson-card-accent.jp { background: linear-gradient(90deg, var(--color-jp-primary), var(--color-jp-accent)); }
.lesson-card-accent.ru { background: linear-gradient(90deg, var(--color-ru-primary), var(--color-ru-secondary)); }
.lesson-card-body {
  padding: 1.25rem;
  flex: 1;
}
.lesson-card-day {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.5rem;
}
.lesson-card-day.jp { color: var(--color-jp-primary); }
.lesson-card-day.ru { color: var(--color-ru-primary); }
.lesson-card h2 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.35rem;
  line-height: 1.4;
}
.lesson-card p {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  line-height: 1.5;
}
.lesson-card .kanji-preview {
  font-family: var(--font-serif-jp);
  font-size: 2.5rem;
  color: var(--color-jp-primary);
  opacity: 0.15;
  float: right;
  margin: -0.5rem -0.25rem 0 0;
  line-height: 1;
}

/* --- About Page --- */
.page-layout {
  max-width: 760px;
  margin: 3rem auto;
  padding: 0 1.25rem;
}
.page-layout h1 { font-size: 2rem; font-weight: 700; margin-bottom: 1rem; }
.page-layout h2 { font-size: 1.3rem; font-weight: 700; margin: 2rem 0 0.75rem; }
.page-layout p { margin-bottom: 1rem; color: #374151; }

/* --- Responsive --- */
@media (max-width: 768px) {
  .main-nav { display: none; }
  .main-nav.open { display: flex; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0; background: var(--color-surface); padding: 1rem; border-bottom: 1px solid var(--color-border); box-shadow: var(--shadow-md); z-index: 99; }
  .nav-toggle { display: block; }
  .today-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .lesson-layout { grid-template-columns: 1fr; }
  .lesson-sidebar { display: none; }
  .calendar-grid { grid-template-columns: repeat(auto-fill, minmax(100px, 1fr)); }
  .steps-grid { grid-template-columns: 1fr 1fr; }
  .hero::before { display: none; }
}
@media (max-width: 480px) {
  .steps-grid { grid-template-columns: 1fr; }
  .vocab-grid { grid-template-columns: 1fr 1fr; }
}

/* --- Utility --- */
.text-jp { font-family: var(--font-serif-jp); }
.mt-2 { margin-top: 0.5rem; }
.mt-4 { margin-top: 1rem; }
.text-muted { color: var(--color-text-muted); }
.tag {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  border-radius: 12px;
  font-size: 0.78rem;
  font-weight: 600;
  background: #f3f4f6;
  color: var(--color-text-muted);
  margin: 0.15rem;
}