/* =====================================================================
   Jackson Wang · Personal Page
   Palette: white + electric blue · type: serif / sans / mono
   ===================================================================== */

/* ---------- Tokens ---------- */
:root {
  --bg: #ffffff;
  --bg-alt: #f7f8fa;
  --bg-soft: #f0f2f6;
  --ink: #0a0e1a;
  --ink-2: #2c3140;
  --ink-3: #5b6470;
  --ink-4: #8a8f99;
  --line: #e6e8ec;
  --line-strong: #0a0e1a;
  --accent: #2a52ff;          /* primary blue */
  --accent-ink: #0a0e1a;
  --accent-soft: #eef1ff;

  --serif: 'Newsreader', 'Noto Serif SC', Georgia, 'Songti SC', serif;
  --sans: 'Inter', 'Noto Sans SC', -apple-system, 'PingFang SC', 'Microsoft YaHei', system-ui, sans-serif;
  --mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;

  --maxw: 1240px;
  --pad-x: clamp(1.25rem, 4vw, 3rem);

  --ease: cubic-bezier(.2,.7,.2,1);
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-feature-settings: 'ss01', 'cv11';
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
button { font: inherit; cursor: pointer; background: none; border: none; color: inherit; }
::selection { background: var(--accent); color: #fff; }

/* ---------- Top bar ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 0.9rem var(--pad-x);
  background: rgba(255,255,255,.85);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
  font-size: 0.85rem;
}
.brand { display: inline-flex; align-items: center; gap: 0.6rem; }
.brand-mark {
  display: grid; place-items: center;
  width: 28px; height: 28px;
  background: var(--ink); color: #fff;
  border-radius: 6px;
  font-family: var(--mono); font-size: 0.72rem; font-weight: 500;
  letter-spacing: 0.05em;
}
.brand-name { font-weight: 600; letter-spacing: 0.005em; }

.topnav {
  display: flex; gap: 1.6rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink-3);
}
.topnav a {
  position: relative;
  transition: color .2s var(--ease);
}
.topnav a::before {
  content: '';
  position: absolute; left: 0; right: 0; bottom: -4px;
  height: 1px; background: var(--ink);
  transform: scaleX(0); transform-origin: left;
  transition: transform .25s var(--ease);
}
.topnav a:hover { color: var(--ink); }
.topnav a:hover::before { transform: scaleX(1); }

.topbar-status {
  justify-self: end;
  display: inline-flex; align-items: center; gap: 0.5rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
}
.status-dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 0 0 rgba(16,185,129,.55);
  animation: pulse 2.4s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(16,185,129,.55); }
  50%      { box-shadow: 0 0 0 6px rgba(16,185,129,0); }
}

/* ---------- Hero ---------- */
.hero {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(2.5rem, 6vw, 5.5rem) var(--pad-x) 0;
}
.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  align-items: end;
}
.kicker {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--accent);
  margin-bottom: 1.25rem;
}
.kicker::before {
  content: '';
  display: inline-block;
  width: 22px; height: 1px; background: var(--accent);
  vertical-align: middle;
  margin-right: 0.7rem;
  margin-bottom: 3px;
}
.display {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(2.6rem, 6.4vw, 5.2rem);
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin-bottom: 1.5rem;
}
.display em {
  font-style: italic;
  font-family: var(--serif);
  color: var(--accent);
  position: relative;
  display: inline-block;
}
.display em::after {
  content: '';
  position: absolute;
  left: -0.04em; right: -0.04em; bottom: 0.08em;
  height: 0.16em;
  background: var(--accent-soft);
  z-index: -1;
  border-radius: 2px;
}
.hero-lede {
  font-size: 1.05rem;
  color: var(--ink-2);
  max-width: 38ch;
  margin-bottom: 2rem;
  line-height: 1.7;
}
.hero-meta {
  display: flex; flex-wrap: wrap; gap: 1.6rem 2.2rem;
  padding: 1.1rem 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  margin-bottom: 2rem;
}
.hero-meta li { display: flex; flex-direction: column; gap: 0.2rem; }
.meta-key {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-4);
}
.meta-val {
  font-size: 0.92rem;
  color: var(--ink);
  font-weight: 500;
}

.hero-cta { display: flex; flex-wrap: wrap; gap: 0.75rem; }
.btn {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.78rem 1.2rem;
  font-size: 0.88rem; font-weight: 500;
  border-radius: 999px;
  transition: transform .2s var(--ease), background .2s var(--ease), color .2s var(--ease), box-shadow .2s var(--ease);
  white-space: nowrap;
}
.btn svg { transition: transform .2s var(--ease); }
.btn:hover svg { transform: translate(2px, -2px); }
.btn-solid {
  background: var(--ink); color: #fff;
  border: 1px solid var(--ink);
}
.btn-solid:hover {
  background: var(--accent);
  border-color: var(--accent);
  box-shadow: 0 6px 20px -8px rgba(42,82,255,.6);
}
.btn-ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--line);
}
.btn-ghost:hover { border-color: var(--ink); }

/* hero photo */
.hero-photo {
  position: relative;
  border-radius: 14px;
  overflow: hidden;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  aspect-ratio: 4 / 5;
  align-self: stretch;
}
.hero-photo img {
  width: 100%; height: 100%; object-fit: cover;
  filter: saturate(.92) contrast(.98);
  transition: transform 1.2s var(--ease);
}
.hero-photo:hover img { transform: scale(1.03); }
.hero-photo figcaption {
  position: absolute; left: 0; right: 0; bottom: 0;
  display: flex; gap: 0.4rem;
  padding: 0.7rem 0.9rem;
  font-family: var(--mono);
  font-size: 0.7rem;
  color: #fff;
  background: linear-gradient(to top, rgba(0,0,0,.55), transparent);
  letter-spacing: 0.04em;
}
.hero-photo .dot { opacity: .6; }

/* marquee */
.marquee {
  margin-top: clamp(3rem, 5vw, 4.5rem);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
  padding: 1rem 0;
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent);
          mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent);
}
.marquee-track {
  display: inline-flex;
  gap: 2.2rem;
  white-space: nowrap;
  animation: marquee 38s linear infinite;
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  color: var(--ink-2);
}
.marquee-track span:nth-child(even) { color: var(--accent); }
@keyframes marquee {
  from { transform: translateX(0); }
  to   { transform: translateX(-50%); }
}

/* ---------- Section base ---------- */
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(4.5rem, 8vw, 7rem) var(--pad-x);
}
.section-head {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: baseline;
  gap: 1rem 1.5rem;
  padding-bottom: 2.4rem;
  border-bottom: 1px solid var(--line);
  margin-bottom: 3rem;
}
.section-num {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.15em;
  color: var(--accent);
  font-weight: 500;
}
.section-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(1.8rem, 3.6vw, 2.8rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--ink);
}
.section-aside {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink-3);
  text-align: right;
}
.section-aside a {
  color: var(--accent);
  border-bottom: 1px solid currentColor;
}

/* ---------- 02 · Work mosaic ---------- */
.work-mosaic {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  grid-auto-rows: minmax(120px, auto);
  gap: 0;
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  background: #fff;
}
.work-card {
  position: relative;
  padding: 1.8rem 1.6rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: #fff;
  transition: background .25s var(--ease);
}
.work-card:hover { background: var(--bg-alt); }

.work-card--feature { grid-column: span 12; }
.work-card--feature .work-title { font-size: clamp(1.5rem, 2.4vw, 2.1rem); }

.work-card[data-size="m"] { grid-column: span 6; }
.work-card--wide        { grid-column: span 12; }
.work-card--small       { grid-column: span 6; }

/* hide last row's bottom border if it spans fully (visual) */
.work-card--wide,
.work-card--feature { border-bottom: 1px solid var(--line); }
.work-card[data-size="m"]:nth-last-of-type(-n+2),
.work-card--small { border-bottom: none; }

.work-card-meta {
  display: flex; align-items: center; flex-wrap: wrap;
  gap: 0.6rem 0.9rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.04em;
}
.work-num {
  display: inline-grid; place-items: center;
  width: 24px; height: 24px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  color: var(--accent);
  font-weight: 500;
}
.work-co { color: var(--ink-2); font-weight: 500; }
.work-period { color: var(--ink-4); }
.work-period::before { content: '· '; opacity: .5; }

.work-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 1.5rem;
  line-height: 1.15;
  letter-spacing: -0.015em;
  color: var(--ink);
}
.work-card--feature .work-title { font-weight: 500; }
.work-desc {
  font-size: 0.95rem;
  color: var(--ink-3);
  line-height: 1.65;
  max-width: 60ch;
}
.work-card--feature .work-desc { font-size: 1.02rem; max-width: 70ch; }

.work-stats {
  display: flex; flex-wrap: wrap; gap: 1.4rem 2.4rem;
  padding-top: 1.2rem;
  margin-top: auto;
  border-top: 1px dashed var(--line);
}
.work-stats > div { display: flex; flex-direction: column; gap: 0.2rem; }
.stat-num {
  font-family: var(--serif);
  font-size: 1.85rem;
  font-weight: 500;
  color: var(--ink);
  letter-spacing: -0.02em;
  line-height: 1;
  font-variant-numeric: tabular-nums;
}
.stat-key {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-4);
}

/* hover affordance on work card */
.work-card::after {
  content: '↗';
  position: absolute; top: 1.4rem; right: 1.4rem;
  font-family: var(--mono);
  font-size: 0.85rem;
  color: var(--ink-4);
  opacity: 0;
  transform: translate(-4px, 4px);
  transition: opacity .2s var(--ease), transform .2s var(--ease), color .2s var(--ease);
}
.work-card:hover::after { opacity: 1; transform: translate(0,0); color: var(--accent); }

/* ---------- 03 · Research ---------- */
.section-research { background: var(--bg-alt); max-width: none; }
.section-research > * { max-width: var(--maxw); margin-left: auto; margin-right: auto; }
.section-research .section-head { padding-bottom: 2rem; }
.research-intro {
  max-width: 70ch;
  margin-bottom: 2.4rem;
  font-size: 1.05rem;
  color: var(--ink-2);
  line-height: 1.75;
}
.research-intro strong { color: var(--ink); font-weight: 600; }
.research-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}
.research-fig {
  margin: 0;
  padding: 1.2rem 1.2rem 0.8rem;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  transition: transform .4s var(--ease), box-shadow .4s var(--ease);
}
.research-fig:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 40px -20px rgba(10,14,26,.18);
}
.research-fig img {
  width: 100%; height: auto;
  border-radius: 6px;
  border: 1px solid var(--line);
}
.research-fig figcaption {
  display: flex; align-items: center; gap: 0.6rem;
  margin-top: 0.9rem;
  padding-top: 0.8rem;
  border-top: 1px dashed var(--line);
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.05em;
}
.fig-tag {
  display: inline-block;
  padding: 0.15rem 0.5rem;
  background: var(--ink);
  color: #fff;
  border-radius: 4px;
  font-size: 0.65rem;
  font-weight: 500;
  letter-spacing: 0.1em;
}
.research-foot {
  font-size: 0.88rem;
  color: var(--ink-3);
}
.research-foot a {
  color: var(--accent);
  border-bottom: 1px solid currentColor;
}

/* ---------- 03 · Off the clock ---------- */
.off-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
  gap: clamp(1.5rem, 3vw, 2.5rem);
  align-items: stretch;
}
.off-photo {
  margin: 0;
  position: relative;
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--bg-soft);
  min-height: 480px;
}
.off-photo img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 1.4s var(--ease);
}
.off-photo:hover img { transform: scale(1.04); }
.off-photo figcaption {
  position: absolute; left: 1rem; bottom: 1rem;
  display: flex; align-items: center; gap: 0.6rem;
  padding: 0.5rem 0.8rem;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(8px);
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--ink);
  letter-spacing: 0.04em;
}
.off-photo .fig-tag { background: var(--accent); }

.off-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 1px;
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  background: var(--line);
}
.off-item {
  position: relative;
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 1rem;
  padding: 1.6rem 1.6rem 1.5rem;
  background: #fff;
  transition: background .25s var(--ease);
  align-content: start;
  overflow: hidden;
}
.off-item::before {
  content: '';
  position: absolute;
  left: 0; top: 1.2rem; bottom: 1.2rem;
  width: 2px;
  background: var(--accent);
  opacity: 0;
  transform: scaleY(.4);
  transform-origin: top;
  transition: opacity .3s var(--ease), transform .3s var(--ease);
}
.off-item:hover { background: var(--accent-soft); }
.off-item:hover::before { opacity: 1; transform: scaleY(1); }
.off-ico {
  font-family: var(--serif);
  font-style: italic;
  font-size: 1.6rem;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: -0.02em;
  line-height: 1;
  padding-top: 0.1rem;
  font-variant-numeric: tabular-nums;
}
.off-body { min-width: 0; }
.off-item h3 {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 1.3rem;
  margin-bottom: 0.5rem;
  letter-spacing: -0.015em;
  color: var(--ink);
}
.off-item h3 em {
  font-style: italic;
  color: var(--accent);
  font-weight: 500;
}
.off-item p {
  font-size: 0.88rem;
  color: var(--ink-3);
  line-height: 1.65;
  font-feature-settings: 'palt';
  padding-left: 0.6rem;
  border-left: 1px solid var(--line);
}
.off-item p.off-cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.45rem 0;
}
.off-item p a {
  color: var(--accent);
  border-bottom: 1px solid currentColor;
}

/* ---------- 04 · Contact ---------- */
.section-contact { background: var(--bg); }
.contact-wrap {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 5rem);
  align-items: start;
  padding: 2rem 0 0;
}
.contact-line {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(2.2rem, 5vw, 3.8rem);
  line-height: 1.05;
  letter-spacing: -0.025em;
  color: var(--ink);
}
.contact-line em {
  font-style: italic;
  color: var(--accent);
  position: relative;
}
.contact-line em::after {
  content: '';
  position: absolute;
  left: -0.04em; right: -0.04em; bottom: 0.08em;
  height: 0.16em;
  background: var(--accent-soft);
  z-index: -1;
  border-radius: 2px;
}
.contact-list {
  display: flex; flex-direction: column;
  border-top: 1px solid var(--line);
}
.contact-list li {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 1rem;
  padding: 1.15rem 0;
  border-bottom: 1px solid var(--line);
  align-items: baseline;
  transition: background .2s var(--ease);
}
.contact-list li:hover { background: var(--bg-alt); }
.ct-key {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-4);
}
.ct-val {
  font-family: var(--serif);
  font-size: 1.1rem;
  color: var(--ink);
  font-weight: 500;
  letter-spacing: -0.01em;
  transition: color .2s var(--ease);
}
a.ct-val:hover { color: var(--accent); }
.contact-foot {
  grid-column: 1 / -1;
  margin-top: 1rem;
  font-size: 0.92rem;
  color: var(--ink-3);
  max-width: 60ch;
  line-height: 1.7;
}

/* ---------- Footer ---------- */
.site-foot {
  border-top: 1px solid var(--line);
  padding: 1.6rem var(--pad-x);
  display: flex; justify-content: space-between;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--ink-4);
  max-width: var(--maxw);
  margin: 0 auto;
  letter-spacing: 0.04em;
}

/* ---------- Reveal animation ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .7s var(--ease), transform .7s var(--ease);
}
[data-reveal].is-in {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .topbar { grid-template-columns: 1fr auto; gap: 0.6rem; }
  .topnav { display: none; }
  .topbar-status { display: none; }

  .hero-grid { grid-template-columns: 1fr; gap: 2rem; }
  .hero-photo { aspect-ratio: 4 / 3; max-height: 420px; }

  .work-mosaic { grid-template-columns: 1fr; }
  .work-card,
  .work-card--feature,
  .work-card--wide,
  .work-card[data-size="m"],
  .work-card--small { grid-column: 1 / -1; }

  .research-grid { grid-template-columns: 1fr; }

  .off-grid { grid-template-columns: 1fr; }
  .off-photo { min-height: 360px; }
  .off-list { grid-template-columns: 1fr; grid-template-rows: auto; gap: 1px; }
  .off-ico { font-size: 1.4rem; }
  .off-item p.off-cols { grid-template-columns: 1fr; gap: 0.4rem; }

  .contact-wrap { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
  .hero { padding-top: 2rem; }
  .display { font-size: clamp(2.2rem, 10vw, 3rem); }
  .section-head { grid-template-columns: 1fr; gap: 0.4rem; }
  .section-aside { text-align: left; }
  .hero-meta { gap: 1rem 1.4rem; }
  .site-foot { flex-direction: column; gap: 0.4rem; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  [data-reveal] { opacity: 1; transform: none; }
  .marquee-track { animation: none; }
}