/* ── Fonts ───────────────────────────────────────────────────────────────── */
@import url("https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:ital,wght@0,300..800;1,300..800&family=Noto+Sans+SC:wght@400;500;700&family=JetBrains+Mono:wght@400;500&display=swap");

/* ── Design tokens ──────────────────────────────────────────────────────── */
:root {
  /* surfaces */
  --bg:              #ffffff;
  --surface:         #f8fafc;
  --border:          #e2e8f0;
  --border-subtle:   #f1f5f9;

  /* brand */
  --accent:          #0e7490;
  --accent-hover:    #0a5e75;
  --accent-soft:     #cffafe;
  --accent-pill:     #ecfeff;

  /* text */
  --text-1:          #0f172a;
  --text-2:          #475569;
  --text-3:          #94a3b8;

  /* cards */
  --card-bg:         #ffffff;
  --card-border:     #e2e8f0;
  --card-shadow:     0 1px 3px rgba(15,23,42,.06), 0 4px 12px rgba(15,23,42,.04);
  --card-shadow-hover: 0 4px 16px rgba(15,23,42,.10), 0 10px 28px rgba(15,23,42,.07);

  /* navbar / footer */
  --bar-bg:          rgba(255,255,255,0.9);
  --bar-border:      #e2e8f0;

  /* inline code */
  --code-bg:         #f1f5f9;
  --code-fg:         #c2410c;
}

body.quarto-dark {
  --bg:              #0d1117;
  --surface:         #161b22;
  --border:          #30363d;
  --border-subtle:   #21262d;

  --accent:          #22d3ee;
  --accent-hover:    #67e8f9;
  --accent-soft:     #083344;
  --accent-pill:     #062030;

  --text-1:          #e6edf3;
  --text-2:          #8b949e;
  --text-3:          #484f58;

  --card-bg:         #161b22;
  --card-border:     #30363d;
  --card-shadow:     0 1px 4px rgba(0,0,0,.4), 0 4px 14px rgba(0,0,0,.25);
  --card-shadow-hover: 0 6px 20px rgba(0,0,0,.5), 0 12px 32px rgba(0,0,0,.35);

  --bar-bg:          rgba(13,17,23,0.92);
  --bar-border:      #30363d;

  --code-bg:         #1e2432;
  --code-fg:         #f97316;
}

/* ── Base ────────────────────────────────────────────────────────────────── */
html { font-synthesis: weight style; scroll-behavior: smooth; }

body {
  font-family: "Plus Jakarta Sans", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text-1);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-hover); }

h1, h2, h3, h4, h5, h6 {
  font-family: "Plus Jakarta Sans", "Noto Sans SC", sans-serif;
  font-weight: 700;
  letter-spacing: -0.015em;
  color: var(--text-1);
}

p { color: var(--text-1); }

/* ── Navbar ──────────────────────────────────────────────────────────────── */
.navbar,
.navbar-dark {
  background-color: var(--bar-bg) !important;
  border-bottom: 1px solid var(--bar-border);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  padding-top: 0.6rem;
  padding-bottom: 0.6rem;
}

body.quarto-dark .navbar,
body.quarto-dark .navbar-dark {
  background-color: var(--bar-bg) !important;
  border-bottom-color: var(--bar-border);
}

.navbar-brand { font-weight: 700; font-size: 1.05rem; }

.navbar .nav-link {
  font-weight: 500;
  font-size: 0.88rem;
  color: var(--text-2) !important;
  letter-spacing: 0.01em;
  transition: color 0.18s ease;
  padding: 0.25rem 0.65rem;
}

.navbar .nav-link:hover,
.navbar .nav-link.active {
  color: var(--accent) !important;
}

.navbar .navbar-nav .dropdown-menu {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  box-shadow: var(--card-shadow);
  padding: 0.4rem 0;
}

.navbar .dropdown-item {
  font-size: 0.87rem;
  color: var(--text-2);
  padding: 0.45rem 1.1rem;
  transition: background 0.15s, color 0.15s;
}

.navbar .dropdown-item:hover {
  background: var(--accent-pill);
  color: var(--accent);
}

/* ── Footer ──────────────────────────────────────────────────────────────── */
.nav-footer {
  background-color: var(--bar-bg);
  border-top: 1px solid var(--bar-border);
  font-size: 0.83rem;
  color: var(--text-3);
  padding: 0.9rem 0;
}

body.quarto-dark .nav-footer {
  background-color: var(--bar-bg);
  border-top-color: var(--bar-border);
}

/* ── Sidebar (TOC + categories) ─────────────────────────────────────────── */
#quarto-margin-sidebar .sidebar-toc-title,
.sidebar-title {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 0.6rem;
}

#quarto-margin-sidebar .nav-link {
  font-size: 0.83rem;
  color: var(--text-2);
  padding: 0.2rem 0.5rem;
  border-radius: 5px;
  transition: color 0.15s, background 0.15s;
}

#quarto-margin-sidebar .nav-link:hover,
#quarto-margin-sidebar .nav-link.active {
  color: var(--accent);
  background: var(--accent-pill);
}

/* hide placeholder images in listing items */
.listing-item-img-placeholder { display: none !important; }

/* ── Listing cards — default (blog / papers / learning) ─────────────────── */
.quarto-post {
  background: transparent;
  border: none;
  border-bottom: 1px solid var(--border-subtle);
  padding: 1.4rem 0;
  transition: background 0.2s;
}

.quarto-post:first-child { padding-top: 0; }
.quarto-post:last-child { border-bottom: none; }

.quarto-post .thumbnail {
  border-radius: 10px;
  overflow: hidden;
  flex-shrink: 0;
}

.quarto-post .thumbnail img,
.thumbnail-image {
  width: 100%;
  height: auto !important;
  object-fit: cover !important;
  border-radius: 10px;
}

.quarto-post .metadata,
.listing-date {
  font-size: 0.8rem;
  color: var(--text-3);
  font-variant-numeric: tabular-nums;
}

.listing-title {
  font-weight: 700;
  font-size: 1.06rem;
  color: var(--text-1);
  letter-spacing: -0.01em;
  line-height: 1.4;
}

.listing-title:hover { color: var(--accent); }

.listing-description {
  font-size: 0.88rem;
  color: var(--text-2);
  line-height: 1.65;
  margin-top: 0.25rem;
}

/* tag badges on listings */
.listing-category,
.quarto-category {
  display: inline-block;
  background: var(--accent-pill);
  border: 1px solid var(--accent-soft);
  color: var(--accent);
  border-radius: 99px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 0.18rem 0.62rem;
  margin: 0.1rem 0.15rem 0.1rem 0;
  transition: background 0.15s, color 0.15s;
}

.listing-category:hover,
.quarto-category:hover {
  background: var(--accent-soft);
  color: var(--accent-hover);
}

/* ── Listing cards — grid (projects) ────────────────────────────────────── */
.quarto-grid-item.card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  box-shadow: var(--card-shadow);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
  overflow: hidden;
}

.quarto-grid-item.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--card-shadow-hover);
  border-color: var(--accent-soft);
}

.quarto-grid-item .card-body {
  background: transparent;
  padding: 1rem 1.1rem 1.1rem;
}

.quarto-grid-item .card-title {
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--text-1);
  letter-spacing: -0.01em;
  margin-bottom: 0.35rem;
}

.quarto-grid-item .card-text {
  font-size: 0.83rem;
  color: var(--text-2);
  line-height: 1.6;
}

.quarto-grid-item .card-img-top,
.quarto-grid-item p.card-img-top {
  height: auto !important;
}

.quarto-grid-item .card-img-top img {
  height: auto !important;
  width: 100%;
  object-fit: cover !important;
  border-radius: 0;
}

/* ── Horizontal listing filter bar ──────────────────────────────────────── */
.listing-filter-bar {
  display: flex;
  align-items: flex-start;
  margin-bottom: 1.8rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-subtle);
}

.listing-filter-bar .quarto-listing-category {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  flex-direction: row;
}

.listing-filter-bar .category,
.listing-filter-bar .quarto-listing-category .category {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.28rem 0.75rem;
  border-radius: 99px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text-2);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
  user-select: none;
}

.listing-filter-bar .category .quarto-category-count {
  font-size: 0.72em;
  color: var(--text-3);
}

.listing-filter-bar .category:hover {
  background: var(--accent-pill);
  border-color: var(--accent-soft);
  color: var(--accent);
}

.listing-filter-bar .category.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.listing-filter-bar .category.active .quarto-category-count {
  color: rgba(255,255,255,0.75);
}

/* hide the old right sidebar categories style (used in fallback/non-JS) */
.quarto-listing-category-title {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 0.5rem;
}

.quarto-listing-category .category {
  font-size: 0.82rem;
  color: var(--text-2);
  padding: 0.22rem 0.5rem;
  border-radius: 6px;
  cursor: pointer;
  transition: color 0.15s, background 0.15s;
  display: flex;
  justify-content: space-between;
}

.quarto-listing-category .category:hover,
.quarto-listing-category .category.active {
  color: var(--accent);
  background: var(--accent-pill);
}

/* ── HOME PAGE ───────────────────────────────────────────────────────────── */
.home-page .home-section {
  margin: 2rem 0 2.5rem;
  padding: 0;
}

.home-page .intro-text {
  font-size: 0.92rem;
  color: var(--text-2);
  margin-bottom: 1.8rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-subtle);
}

/* section heading with arrow link */
.home-page h2 {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 1.2rem;
  padding: 0;
  border: none;
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-1);
  letter-spacing: -0.02em;
}

.home-page h2 a {
  color: var(--text-1);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.45rem;
  transition: color 0.18s;
}

.home-page h2 a:hover { color: var(--accent); }

.home-page h2 a::after {
  content: "→";
  font-size: 0.95em;
  font-weight: 400;
  opacity: 0.45;
  transition: opacity 0.18s, transform 0.18s;
}

.home-page h2 a:hover::after {
  opacity: 0.9;
  transform: translateX(3px);
}

/* remove old box from h2::before if present */
.home-page h2 a::before { display: none; }

/* section divider line before heading */
.home-page .home-section + .home-section {
  border-top: 1px solid var(--border-subtle);
  padding-top: 2rem;
}

/* hide categories sidebar on HOME page */
.home-page .quarto-listing-category { display: none !important; }
.home-page #quarto-margin-sidebar .quarto-listing-category { display: none !important; }

.home-page .quarto-listing-container-grid,
.home-page .quarto-listing-container-default,
.home-page .quarto-listing { background: transparent; }

/* ── ARTICLE / POST PAGES ────────────────────────────────────────────────── */
.quarto-title-block {
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
}

.quarto-title-block .title {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  line-height: 1.25;
  color: var(--text-1);
  margin-bottom: 0.5rem;
}

.quarto-title-meta {
  font-size: 0.82rem;
  color: var(--text-3);
  margin-top: 0.75rem;
}

.quarto-title-meta-heading {
  font-size: 0.72rem;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--text-3);
  font-weight: 600;
}

/* article body typography */
#quarto-document-content p,
.content p {
  line-height: 1.8;
  color: var(--text-1);
  font-size: 0.97rem;
}

#quarto-document-content h2 {
  font-size: 1.45rem;
  margin-top: 2.4rem;
  margin-bottom: 0.8rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border-subtle);
}

#quarto-document-content h3 {
  font-size: 1.15rem;
  margin-top: 1.8rem;
  margin-bottom: 0.55rem;
}

#quarto-document-content h4 {
  font-size: 1rem;
  margin-top: 1.4rem;
  margin-bottom: 0.4rem;
  color: var(--text-2);
}

/* inline code */
code:not(pre code) {
  background: var(--code-bg);
  color: var(--code-fg);
  border-radius: 5px;
  padding: 0.14em 0.45em;
  font-family: "JetBrains Mono", "SF Mono", "Fira Code", monospace;
  font-size: 0.83em;
  font-weight: 500;
}

/* code blocks */
pre {
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--code-bg) !important;
  font-family: "JetBrains Mono", "SF Mono", "Fira Code", monospace;
  font-size: 0.84em;
  line-height: 1.65;
  overflow-x: auto;
}

div.sourceCode {
  border-radius: 10px;
  border: 1px solid var(--border);
  overflow: hidden;
  margin: 1.2em 0;
}

div.sourceCode pre {
  border: none;
  border-radius: 0;
  margin: 0;
}

/* ── ABOUT PAGE ──────────────────────────────────────────────────────────── */
body.about-page {
  font-family: "Plus Jakarta Sans", "Noto Sans SC", sans-serif;
}

/* hero strip at top of about */
.about-page .quarto-title-block {
  border-bottom: none;
  padding-bottom: 0;
  margin-bottom: 1rem;
}

.about-page .quarto-title-block .title {
  font-family: "Plus Jakarta Sans", "Noto Sans SC", sans-serif;
  font-size: 2.4rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--accent);
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 0;
}

.about-page .quarto-title-block .title::after {
  content: "";
  flex: 1;
  min-width: 40px;
  height: 2px;
  background: linear-gradient(to right, var(--border), transparent);
  border-radius: 999px;
}

.about-page .quarto-title-block .subtitle.lead {
  display: none;
}

/* social icon row */
.about-page .about-icons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin: 0.5rem 0 1.8rem;
}

.about-page .about-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.2rem;
  height: 2.2rem;
  border-radius: 8px;
  border: 1.5px solid var(--border);
  background: var(--surface);
  color: var(--text-2);
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.about-page .about-icon:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: 0 6px 16px rgba(14,116,144,.15);
}

/* wrap */
.about-page .about-wrap {
  max-width: 820px;
  margin: 0 auto;
}

/* intro paragraph */
.about-page .about-intro {
  font-size: 1.08rem;
  line-height: 1.7;
  color: var(--text-1);
  margin-bottom: 0.5rem;
}

.about-page .about-highlight {
  font-size: 0.92rem;
  color: var(--text-2);
  margin-bottom: 0;
}

.about-page .about-highlight a {
  color: var(--accent);
  font-weight: 500;
}

/* section headings */
.about-page h2 {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-top: 2.2rem;
  margin-bottom: 0.9rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-subtle);
}

/* focus list */
.about-page .about-focus {
  list-style: none;
  padding: 0;
  margin: 0 0 0.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.about-page .about-focus li {
  background: var(--accent-pill);
  border: 1px solid var(--accent-soft);
  color: var(--accent-hover);
  border-radius: 99px;
  font-size: 0.85rem;
  font-weight: 500;
  padding: 0.3rem 0.85rem;
}

/* timeline */
.about-page .about-timeline {
  list-style: none;
  padding: 0;
  margin: 0 0 0.5rem;
}

.about-page .about-timeline li {
  position: relative;
  padding: 0.9rem 0 0.9rem 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.1rem;
}

.about-page .about-timeline li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.about-page .about-timeline li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 1.15rem;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.about-page .about-time {
  font-size: 0.78rem;
  color: var(--text-3);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

.about-page .about-title {
  font-size: 0.97rem;
  font-weight: 700;
  color: var(--text-1);
  margin-top: 0.1rem;
}

.about-page .about-sub {
  font-size: 0.87rem;
  color: var(--text-2);
  line-height: 1.5;
  margin-top: 0.1rem;
}

.about-page .about-links {
  font-size: 0.83rem;
  margin-top: 0.2rem;
}

.about-page .about-links a {
  color: var(--accent);
  font-weight: 500;
}

.about-page .about-links a:hover { text-decoration: underline; }

/* tags / tech stack */
.about-page .about-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.2rem;
}

/* pandoc wraps spans in a <p>; make it a transparent flex passthrough */
.about-page .about-tags > p {
  display: contents;
}

.about-page .about-tag {
  white-space: nowrap;   /* never break inside a pill */
  padding: 0.32rem 0.85rem;
  border-radius: 99px;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-2);
  font-size: 0.83rem;
  font-weight: 500;
  transition: border-color 0.15s, color 0.15s, background 0.15s;
}

.about-page .about-tag:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-pill);
}

.about-page .about-tag-accent {
  background: var(--accent-pill);
  border-color: var(--accent-soft);
  color: var(--accent-hover);
}

/* dark-mode about overrides */
body.quarto-dark.about-page .about-icon {
  background: var(--surface);
  color: var(--text-2);
}

body.quarto-dark.about-page .about-timeline li::before {
  box-shadow: 0 0 0 3px var(--accent-soft);
}

/* ── Language toggle ────────────────────────────────────────────────────── */
.lang-zh,
.lang-en { transition: opacity 0.22s ease; }

body[data-lang="zh"] .lang-en,
body[data-lang="en"] .lang-zh { display: none; }

body:not([data-lang]) .lang-en { display: none; }

#lang-toggle {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  padding: 0.45rem 0.9rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text-2);
  font-family: "Plus Jakarta Sans", sans-serif;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  box-shadow: 0 4px 16px rgba(40,30,20,.14);
  z-index: 9999;
  transition: background 0.18s, color 0.18s, border-color 0.18s, transform 0.18s;
}

#lang-toggle:hover {
  background: var(--accent-pill);
  color: var(--accent);
  border-color: var(--accent-soft);
  transform: translateY(-1px);
}

body.quarto-dark #lang-toggle {
  background: var(--surface);
  color: var(--text-2);
  border-color: var(--border);
}

body.quarto-dark #lang-toggle:hover {
  background: var(--accent-soft);
  color: var(--accent);
}

/* ── Callout blocks ─────────────────────────────────────────────────────── */
.callout {
  border-radius: 10px;
  border-left-width: 4px;
}

/* ── Pagination ─────────────────────────────────────────────────────────── */
.pagination .page-link {
  color: var(--accent);
  background: var(--surface);
  border-color: var(--border);
  border-radius: 7px;
}

.pagination .page-link:hover,
.pagination .page-item.active .page-link {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

/* ── Search ─────────────────────────────────────────────────────────────── */
.navbar .aa-Form {
  border-radius: 8px;
  border-color: var(--border);
  background: var(--surface);
}

/* ── About page two-column grid ─────────────────────────────────────────── */
.about-page .about-grid {
  display: grid;
  grid-template-columns: 1fr 1.65fr;
  gap: 3rem 4rem;
  margin-top: 0.5rem;
  align-items: start;
}

.about-page .about-col-left {
  position: sticky;
  top: 4.5rem;           /* below fixed navbar */
}

/* Left column has lighter section headings to not compete with right */
.about-page .about-col-left h2 {
  margin-top: 1.6rem;
}

.about-page .about-col-left .about-focus {
  margin-bottom: 0;
}

/* Right column vertical separator */
.about-page .about-col-right {
  border-left: 1px solid var(--border-subtle);
  padding-left: 2.5rem;
}

/* ── Article reading experience ─────────────────────────────────────────── */
/* Better line-height and prose width for article / learning-note pages */
.page-layout-article #quarto-document-content p,
.page-layout-article #quarto-document-content li,
.page-layout-article #quarto-document-content blockquote {
  line-height: 1.88;
  font-size: 1rem;
}

/* Constrain prose column width to ~720px on wide screens */
@media (min-width: 1200px) {
  .page-layout-article main.content {
    max-width: 860px;
  }
}

/* ── Reading progress bar (CSS Scroll-Driven Animations) ────────────────── */
@supports (animation-timeline: scroll()) {
  @keyframes reading-progress {
    from { transform: scaleX(0); }
    to   { transform: scaleX(1); }
  }

  body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(to right, var(--accent), var(--accent-hover));
    transform: scaleX(0);
    transform-origin: left center;
    z-index: 99999;
    animation: reading-progress linear both;
    animation-timeline: scroll(root);
  }
}

/* ── Dark mode refinements ──────────────────────────────────────────────── */
body.quarto-dark {
  background: var(--bg);
}

body.quarto-dark .quarto-grid-item.card {
  background: var(--card-bg);
  border-color: var(--card-border);
}

body.quarto-dark .quarto-post {
  border-bottom-color: var(--border-subtle);
}

body.quarto-dark .listing-title { color: var(--text-1); }

body.quarto-dark code:not(pre code) {
  background: var(--code-bg);
  color: var(--code-fg);
}

body.quarto-dark pre,
body.quarto-dark div.sourceCode {
  background: var(--code-bg) !important;
  border-color: var(--border);
}

body.quarto-dark .listing-filter-bar .category {
  background: var(--surface);
  border-color: var(--border);
  color: var(--text-2);
}

body.quarto-dark .listing-filter-bar .category.active {
  background: var(--accent);
  color: #000;
}

body.quarto-dark .nav-footer {
  color: var(--text-3);
}

/* ── Responsive ─────────────────────────────────────────────────────────── */
@media (max-width: 1024px) {
  .about-page .about-grid {
    gap: 2rem 2.5rem;
  }

  .about-page .about-col-left {
    position: static;     /* unstick on smaller screens */
  }
}

@media (max-width: 768px) {
  /* About: stack columns */
  .about-page .about-grid {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .about-page .about-col-left {
    padding-bottom: 1.5rem;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid var(--border-subtle);
  }

  .about-page .about-col-right {
    border-left: none;
    padding-left: 0;
  }

  /* Title sizes */
  .about-page .quarto-title-block .title { font-size: 1.9rem; }
  .about-page .quarto-title-block .title::after { display: none; }
  .quarto-title-block .title { font-size: 1.5rem; }

  /* Home */
  .home-page h2 { font-size: 1rem; }

  /* Filter bar scrollable on mobile */
  .listing-filter-bar {
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-bottom: 0.5rem;
    -webkit-overflow-scrolling: touch;
  }

  .listing-filter-bar .quarto-listing-category {
    flex-wrap: nowrap;
  }
}

@media (max-width: 992px) {
  .about-page .quarto-title-block .title { font-size: 2rem; }
  .quarto-title-block .title { font-size: 1.65rem; }
}