/* ============================================================
   Pac-Man dissertation — case study
   Self-contained; mirrors the portfolio tokens.
   ============================================================ */
:root {
  --bg: #0a0a0b;
  --surface-1: #131316;
  --surface-2: #1a1a1e;
  --ink: #ededf0;
  --ink-dim: rgba(237, 237, 240, 0.66);
  --ink-faint: rgba(237, 237, 240, 0.42);
  --line: rgba(237, 237, 240, 0.12);
  --line-strong: rgba(237, 237, 240, 0.24);
  --accent: #ffd21e;
  --accent-soft: rgba(255, 210, 30, 0.14);
  --bad: #ff6b6b;
  --font-display: "Bricolage Grotesque", "Hanken Grotesk", system-ui, sans-serif;
  --font-body: "Hanken Grotesk", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  --maxw: 1080px;
  --gutter: clamp(1.1rem, 4vw, 2rem);
  --ease: cubic-bezier(0.2, 0, 0, 1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  position: relative;
}

/* Background: slow lattice drift (exact 128px period) under a top fade, plus a faint accent bloom */
body::before {
  content: "";
  position: fixed;
  inset: -128px;
  z-index: -2;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(30deg, var(--line) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(150deg, var(--line) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(90deg, var(--line) 0 1px, transparent 1px 64px);
  opacity: 0.4;
  animation: lattice-drift 70s linear infinite;
}
body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(50% 36% at 12% 0%, var(--accent-soft), transparent 70%),
    radial-gradient(120% 80% at 50% 0%, transparent 0%, var(--bg) 72%);
}
@keyframes lattice-drift { to { transform: translate3d(128px, 0, 0); } }

a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; height: auto; }
b { font-weight: 700; }
em { font-style: italic; }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

.wrap { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--gutter); }

/* ---------- Top bar ---------- */
.bar-top {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(10, 10, 11, 0.78);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.bar-top__inner { display: flex; align-items: center; justify-content: space-between; height: 3.25rem; }
.back, .bar-top__pdf {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  color: var(--ink-dim);
  transition: color 0.2s var(--ease);
}
.back:hover, .bar-top__pdf:hover { color: var(--accent); }
.back span { display: inline-block; transition: transform 0.2s var(--ease); }
.back:hover span { transform: translateX(-3px); }
.bar-top__pdf { border: 1px solid var(--line-strong); border-radius: 999px; padding: 0.3rem 0.8rem; }

/* ---------- Hero ---------- */
.hero { padding-top: clamp(3rem, 8vw, 6rem); padding-bottom: clamp(2.5rem, 6vw, 4.5rem); }
.hero__meta {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.04em;
  color: var(--ink-faint);
  margin-bottom: 1.4rem;
}
.hero__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(3.1rem, 11vw, 7.2rem);
  line-height: 0.92;
  letter-spacing: -0.035em;
}
.hero__title .vs {
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: 0.32em;
  letter-spacing: 0;
  color: var(--ink-faint);
  vertical-align: 0.5em;
  margin-inline: 0.25em;
}
.hero__sub {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(1.15rem, 2.6vw, 1.6rem);
  line-height: 1.3;
  color: var(--ink-dim);
  margin-top: 1.1rem;
}
.pac { color: var(--accent); }

.hero__body { margin-top: clamp(1.8rem, 4vw, 2.6rem); max-width: 40rem; }
.hero__lede { font-size: 1.08rem; color: var(--ink); }
.hero__lede + .hero__lede { margin-top: 0.9rem; }
.hero__lede--dim { color: var(--ink-dim); font-size: 1rem; }
.hero__lede b { color: var(--accent); }

/* ---------- Buttons ---------- */
.cta { display: flex; flex-wrap: wrap; gap: 0.7rem; margin-top: 1.7rem; }
.cta--center { justify-content: center; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.72rem 1.15rem;
  border-radius: 10px;
  border: 1px solid var(--line-strong);
  font-weight: 600;
  font-size: 0.95rem;
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease), background-color 0.2s var(--ease), color 0.2s var(--ease);
}
.btn:hover { transform: translateY(-2px); border-color: var(--ink-dim); }
.btn--primary { background: var(--accent); border-color: var(--accent); color: #0a0a0b; }
.btn--primary:hover { border-color: var(--accent); background: #ffdd55; }
.btn__sub { font-family: var(--font-mono); font-size: 0.72rem; font-weight: 500; opacity: 0.7; }
.ico { width: 1.1rem; height: 1.1rem; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; flex-shrink: 0; }

.stack { display: flex; flex-wrap: wrap; gap: 0.4rem; list-style: none; margin-top: 1.6rem; }
.stack li {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--ink-dim);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 0.22rem 0.55rem;
}

/* ---------- Headline metrics ---------- */
.metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  margin-top: clamp(2.2rem, 5vw, 3.4rem);
  border-top: 1px solid var(--line-strong);
}
.metric { padding: 1.1rem 1.1rem 0.4rem 0; }
.metric + .metric { padding-left: 1.1rem; border-left: 1px solid var(--line); }
.metric dt {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  color: var(--ink-faint);
}
.metric dd { display: flex; flex-direction: column; }
.metric__big {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2rem, 4.2vw, 3rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--accent);
  margin-top: 0.35rem;
}
.metric__big small { font-size: 0.55em; font-weight: 600; margin-left: 0.05em; }
.metric__vs { font-size: 0.9rem; color: var(--ink); margin-top: 0.1rem; }
.metric__note { font-family: var(--font-mono); font-size: 0.7rem; color: var(--ink-faint); margin-top: 0.35rem; }

/* ---------- Sections ---------- */
.sec {
  display: grid;
  grid-template-columns: 4.5rem minmax(0, 1fr);
  gap: 0 1.5rem;
  padding-block: clamp(2.6rem, 6vw, 4.6rem);
  border-top: 1px solid var(--line);
}
.sec__num {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent);
  padding-top: 0.55rem;
}
.sec__body { min-width: 0; max-width: 46rem; }
.sec h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.7rem, 3.8vw, 2.5rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  text-wrap: balance;
}
.sec h3.sub { font-family: var(--font-display); font-size: 1.15rem; margin: 2.4rem 0 0.9rem; }
.prose { margin-top: 1.1rem; }
.prose p { color: var(--ink-dim); font-size: 1.04rem; }
.prose p + p { margin-top: 0.9rem; }
.prose em { color: var(--ink); }
.note { margin-top: 1rem; font-size: 0.92rem; color: var(--ink-dim); }

/* Conditions list */
.conditions {
  list-style: none;
  margin-top: 1.8rem;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}
.conditions li {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  padding: 0.9rem 1rem;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.conditions b { font-family: var(--font-mono); font-size: 0.85rem; }
.conditions span { font-size: 0.88rem; color: var(--ink-dim); }

/* 29-D vector */
.vec { margin-top: 2rem; }
.vec__cells { display: grid; grid-template-columns: 24fr 3fr 2fr; gap: 0.7rem; }
.vec__group { min-width: 0; }
.vec__row { display: flex; gap: 3px; }
.vec__row span { flex: 1; height: 26px; border-radius: 2px; }
.vec__group--a .vec__row span { background: var(--accent); }
.vec__group--a .vec__row span:nth-child(6n) { margin-right: 6px; }
.vec__group--a .vec__row span:nth-child(24) { margin-right: 0; }
.vec__group--b .vec__row span { background: var(--ink); opacity: 0.75; }
.vec__group--c .vec__row span { outline: 1px solid var(--ink-dim); outline-offset: -1px; }
.vec__group small {
  display: block;
  margin-top: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.66rem;
  color: var(--ink-faint);
  white-space: nowrap;
}
.vec__legend { margin-top: 1.2rem; display: grid; gap: 1rem; }
.vec__item { padding-left: 0.9rem; border-left: 2px solid var(--line-strong); }
.vec__item--a { border-color: var(--accent); }
.vec__item--b { border-color: var(--ink-dim); }
.vec__item b { font-family: var(--font-mono); font-size: 0.8rem; font-weight: 500; }
.vec__item p { color: var(--ink-dim); font-size: 0.93rem; margin-top: 0.15rem; }

.split { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; margin-top: 2.4rem; padding-top: 1.4rem; border-top: 1px solid var(--line); }
.split h3 { font-family: var(--font-display); font-size: 1.1rem; margin-bottom: 0.6rem; }
.split ul { list-style: none; }
.split li { color: var(--ink-dim); font-size: 0.93rem; padding: 0.4rem 0; border-bottom: 1px solid var(--line); }
.split li:last-child { border-bottom: 0; }

/* Duel bars */
.duel { margin-top: 2rem; }
.duel__key { display: flex; gap: 1.2rem; font-family: var(--font-mono); font-size: 0.74rem; color: var(--ink-dim); margin-bottom: 0.4rem; }
.k { display: inline-flex; align-items: center; gap: 0.45rem; }
.k::before { content: ""; width: 0.7rem; height: 0.7rem; border-radius: 2px; background: var(--ink-faint); }
.k--neat::before { background: var(--accent); }

.duel__row {
  display: grid;
  grid-template-columns: 9.5rem minmax(0, 1fr) 7.2rem;
  align-items: center;
  gap: 1rem;
  padding-block: 0.85rem;
  border-top: 1px solid var(--line);
}
.duel__label { font-size: 0.95rem; }
.duel__bars { display: grid; gap: 0.35rem; }
.bar { display: flex; align-items: center; gap: 0.6rem; height: 1.15rem; }
.bar__fill {
  display: block;
  height: 100%;
  border-radius: 3px;
  background: var(--ink-faint);
  transform-origin: left center;
  transition: transform 0.9s var(--ease);
}
.bar--neat .bar__fill { background: var(--accent); }
.bar__val { font-family: var(--font-mono); font-size: 0.78rem; color: var(--ink); white-space: nowrap; }
.duel__sig { font-family: var(--font-mono); font-size: 0.72rem; color: var(--ink-dim); text-align: right; }
.duel__sig--ns { color: var(--ink-faint); }
.duel__foot { font-size: 0.82rem; color: var(--ink-faint); padding-top: 0.9rem; border-top: 1px solid var(--line); }

/* NEAT fills the track (minus room for its value label); DQN is proportional to it */
.bar--neat .bar__fill { width: calc(100% - 4.6rem); }
.bar--dqn .bar__fill { width: calc((100% - 4.6rem) * var(--dqn) / 100); }

.js .duel__row .bar__fill { transform: scaleX(0); }
.js .duel__row.is-in .bar__fill { transform: scaleX(1); }
.js .duel__row.is-in .bar--neat .bar__fill { transition-delay: 0.12s; }

/* Table */
.tablewrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 8px; scrollbar-width: thin; scrollbar-color: var(--line-strong) transparent; }
table { width: 100%; border-collapse: collapse; font-size: 0.88rem; min-width: 34rem; }
th, td { padding: 0.7rem 0.6rem; text-align: right; border-bottom: 1px solid var(--line); white-space: nowrap; }
th:first-child, td:first-child { padding-left: 0.8rem; }
th:last-child, td:last-child { padding-right: 0.8rem; }
thead th {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 0.7rem;
  letter-spacing: 0.03em;
  color: var(--ink-faint);
}
tbody th { text-align: left; font-family: var(--font-mono); font-weight: 500; font-size: 0.82rem; }
thead th:first-child { text-align: left; }
tbody tr:last-child > * { border-bottom: 0; }
tbody td { font-variant-numeric: tabular-nums; color: var(--ink-dim); }
.is-best th, .is-best td { color: var(--ink); background: var(--accent-soft); }
.is-best td:nth-child(4) { color: var(--accent); font-weight: 700; }

/* Memorisation matrix */
.mem { margin-top: 2rem; border-top: 1px solid var(--line-strong); }
.mem__head, .mem__row { display: grid; grid-template-columns: 3.5rem 1fr 1fr; gap: 0 1rem; }
.mem__head {
  padding: 0.7rem 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--ink-faint);
  border-bottom: 1px solid var(--line);
}
.mem__row { padding: 0.8rem 0; }
.mem__row--result { border-bottom: 1px solid var(--line); padding-top: 0; }
.mem__algo { font-family: var(--font-mono); font-size: 0.85rem; padding-top: 0.2rem; }
.mem__cell { display: flex; flex-direction: column; }
.mem__cell small { font-family: var(--font-mono); font-size: 0.68rem; color: var(--ink-faint); }
.mem__cell b {
  font-family: var(--font-display);
  font-size: 1.9rem;
  line-height: 1.15;
  letter-spacing: -0.02em;
}
.mem__cell i { font-style: normal; font-family: var(--font-mono); font-size: 0.74rem; color: var(--ink-dim); }
.mem__cell--bad b { color: var(--bad); }
.mem__cell--good b { color: var(--accent); }

/* Engineering list */
.eng { list-style: none; margin-top: 1.6rem; }
.eng li {
  display: grid;
  grid-template-columns: 8.5rem minmax(0, 1fr);
  gap: 1.5rem;
  padding-block: 1.4rem;
  border-top: 1px solid var(--line);
}
.eng__stat { display: flex; flex-direction: column; font-family: var(--font-display); line-height: 1.05; }
.eng__stat b { font-size: 1.7rem; letter-spacing: -0.02em; color: var(--accent); }
.eng__stat span { font-family: var(--font-mono); font-size: 0.72rem; color: var(--ink-faint); margin-top: 0.3rem; }
.eng__stat b + span[aria-hidden] { font-size: 1rem; margin: 0.1rem 0; color: var(--ink-faint); }
.eng__txt h3 { font-family: var(--font-display); font-size: 1.2rem; letter-spacing: -0.01em; }
.eng__txt p { margin-top: 0.35rem; color: var(--ink-dim); font-size: 0.97rem; }

.shot { margin-top: 1.4rem; }
.shot img { border: 1px solid var(--line-strong); border-radius: 10px; width: 100%; }
.shot figcaption { margin-top: 0.7rem; font-family: var(--font-mono); font-size: 0.74rem; color: var(--ink-faint); }

/* Limits */
.limits { list-style: none; margin-top: 1.4rem; }
.limits li {
  position: relative;
  padding: 0.85rem 0 0.85rem 1.4rem;
  border-top: 1px solid var(--line);
  color: var(--ink-dim);
}
.limits li::before { content: ""; position: absolute; left: 0; top: 1.5rem; width: 0.55rem; height: 1px; background: var(--accent); }
.limits em { color: var(--ink); }

/* End CTA */
.end { text-align: center; padding-block: clamp(3rem, 7vw, 5.5rem); border-top: 1px solid var(--line); }
.end h2 { font-family: var(--font-display); font-weight: 700; font-size: clamp(1.8rem, 4vw, 2.6rem); letter-spacing: -0.02em; }
.end p { color: var(--ink-dim); margin-top: 0.6rem; }

.foot { border-top: 1px solid var(--line); padding-block: 1.4rem; font-family: var(--font-mono); font-size: 0.76rem; color: var(--ink-faint); }
.foot__inner { display: flex; justify-content: space-between; gap: 1rem; flex-wrap: wrap; }
.foot a:hover { color: var(--accent); }

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  .metrics { grid-template-columns: repeat(2, 1fr); }
  .metric:nth-child(3) { padding-left: 0; border-left: 0; }
  .metric:nth-child(n+3) { border-top: 1px solid var(--line); }
  .split { grid-template-columns: 1fr; gap: 1.6rem; }
}
@media (max-width: 680px) {
  .sec { grid-template-columns: 1fr; }
  .sec__num { padding: 0 0 0.5rem; }
  .duel__row { grid-template-columns: 1fr; gap: 0.5rem; }
  .duel__sig { text-align: left; }
  .eng li { grid-template-columns: 1fr; gap: 0.6rem; }
  .eng__stat { flex-direction: row; align-items: baseline; gap: 0.6rem; }
  .eng__stat span, .eng__stat b + span[aria-hidden] { margin: 0; }
  .conditions { grid-template-columns: 1fr; }
  .mem__head, .mem__row { grid-template-columns: 2.6rem 1fr 1fr; gap: 0 0.6rem; }
  .mem__cell b { font-size: 1.5rem; }
}
@media (max-width: 420px) {
  .metrics { grid-template-columns: 1fr; }
  .metric + .metric { padding-left: 0; border-left: 0; border-top: 1px solid var(--line); }
  .btn { width: 100%; justify-content: center; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  body::before { animation: none; }
  .js .duel__row .bar__fill { transform: none; transition: none; }
  .btn, .back span { transition: none; }
}