/* Page design taken from the PGPG project page (ducido.github.io/pgpg.github.io), itself adapted from R2A.
   SDN colors follow Fig. 1 of the paper: blue is the positive set G, red the negative set B,
   green the selected action chunk. */
:root {
  --paper: #ffffff;
  --ink: #16202a;
  --muted: #58606e;
  --faint: #8b949c;
  --rule: #e1e6ef;
  --card: #ffffff;
  --coral: #e0503a;
  --coral-tint: #fff3ef;
  --deep: #900300;
  --exec: #1e8449;
  --policy: #c0392b;
  --brand: #2f5fd0;
  --brand-2: #7f9df0;
  --brand-tint: #eef3fe;
  --grid: rgba(30, 40, 70, 0.035);
  --shadow: 0 1px 2px rgba(30, 50, 120, 0.05), 0 10px 30px rgba(40, 70, 160, 0.08);

  --pos: #2e6fd6;
  --pos-tint: #e8f0fc;
  --neg: #c62828;
  --neg-tint: #fdecec;
  --pick: #2e8b3e;
  --pick-tint: #e7f4e8;

  color-scheme: light;
  --serif: "STIX Two Text", "Times New Roman", Times, serif;
  --sans: "Inter", ui-sans-serif, system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body {
  margin: 0;
  background-color: var(--paper);
  background-image: radial-gradient(var(--grid) 1px, transparent 1px);
  background-size: 22px 22px;
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
}
h1, h2, h3 { font-family: var(--serif); font-weight: 600; letter-spacing: -0.01em; margin: 0; }
a { color: var(--brand); }
img { max-width: 100%; height: auto; display: block; }
sub, sup { line-height: 0; }
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 16px; }
@media (min-width: 720px) { .wrap { padding: 0 28px; } }

#progress { position: fixed; inset: 0 auto auto 0; height: 3px; width: 0; z-index: 60;
  background: linear-gradient(90deg, var(--pos), var(--neg)); }

/* side nav */
.side-nav { position: fixed; left: 22px; top: 50%; transform: translateY(-50%); z-index: 40; display: none; }
@media (min-width: 1380px) { .side-nav { display: block; } }
.side-nav .cap { font-size: 10px; letter-spacing: 0.24em; text-transform: uppercase; color: var(--faint); margin: 0 0 14px 22px; }
.side-nav ol { list-style: none; margin: 0; padding: 0; border-left: 1px solid var(--rule); }
.side-nav li a { display: flex; gap: 10px; align-items: baseline; padding: 5px 0 5px 20px; margin-left: -1px;
  border-left: 2px solid transparent; text-decoration: none; color: var(--muted); font-family: var(--serif); font-size: 15px; }
.side-nav li a span { font-family: var(--mono); font-size: 11px; color: var(--faint); }
.side-nav li a.on { color: var(--ink); border-left-color: var(--brand); }
.side-nav li a.on span { color: var(--brand); }

/* hero */
header.hero { padding: 64px 0 24px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip { font-size: 11px; font-weight: 600; letter-spacing: 0.14em; text-transform: uppercase; color: var(--muted);
  border: 1px solid var(--rule); background: var(--card); border-radius: 999px; padding: 4px 11px; }
.chip.hot { color: var(--deep); border-color: color-mix(in srgb, var(--deep) 35%, transparent); }
.hero h1 { margin-top: 26px; font-size: clamp(36px, 6vw, 64px); line-height: 1.05; font-weight: 700; }
.hero h1 .acr { background: linear-gradient(100deg, var(--pos) 15%, #7a4fc4 55%, var(--neg)); -webkit-background-clip: text;
  background-clip: text; color: transparent; }
.hero .sub { display: block; margin-top: 12px; font-size: clamp(21px, 3vw, 31px); font-weight: 400; font-style: italic;
  color: var(--muted); line-height: 1.22; }
.hero .sub b { font-style: normal; font-weight: 600; color: var(--brand); }
.authors { margin: 26px 0 0; font-size: 16.5px; line-height: 1.75; color: var(--ink); max-width: 900px; }
.authors span { white-space: nowrap; }
.authors sup { font-size: 10.5px; color: var(--muted); margin-left: 1px; }
.affils { margin: 8px 0 0; font-size: 13.5px; line-height: 1.6; color: var(--muted); max-width: 900px; }
.affils span { white-space: nowrap; margin-right: 12px; }
.logos { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 18px; }
.logos span { flex: 1 1 auto; display: flex; align-items: center; justify-content: center; height: 84px; padding: 10px 18px; }
.logos img { width: auto; max-width: 100%; }
.venue { margin: 10px 0 0; font-family: var(--serif); font-style: italic; font-size: 17px; color: var(--muted); }
.links { margin-top: 22px; display: flex; flex-wrap: wrap; gap: 10px; }
.btn { display: inline-flex; align-items: center; gap: 8px; border-radius: 999px; padding: 9px 18px; font-size: 14px; font-weight: 500;
  text-decoration: none; background: var(--ink); color: var(--paper); border: 1px solid var(--ink); transition: background 0.15s, border-color 0.15s; }
.btn:hover { background: var(--brand); border-color: var(--brand); }
.btn.ghost { background: transparent; color: var(--ink); }
.btn.ghost:hover { color: #fff; }
.btn.off { opacity: 0.45; pointer-events: none; }
.btn svg { width: 16px; height: 16px; }

.stats { margin-top: 36px; display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px; background: var(--rule);
  border: 1px solid var(--rule); border-radius: 14px; overflow: hidden; }
@media (min-width: 820px) { .stats { grid-template-columns: repeat(4, 1fr); } }
.stat { background: var(--card); padding: 18px 18px 16px; }
.stat .n { font-family: var(--serif); font-size: 34px; line-height: 1; font-weight: 700; color: var(--ink); }
.stat .n small { font-size: 16px; font-weight: 600; color: var(--exec); margin-left: 6px; }
.stat .l { margin-top: 8px; font-size: 13px; color: var(--muted); line-height: 1.4; }

/* sections */
section { padding: 34px 0 44px; }
.sec-head { border-top: 1px solid var(--rule); padding-top: 30px; margin-bottom: 24px; }
.kicker { font-size: 11px; font-weight: 600; letter-spacing: 0.22em; text-transform: uppercase; color: var(--coral); }
.sec-head h2 { margin-top: 8px; font-size: clamp(28px, 4vw, 40px); line-height: 1.08; }
.lede { font-family: var(--serif); font-size: 19px; line-height: 1.6; color: var(--ink); max-width: 820px; }
.muted { color: var(--muted); }
.small { font-size: 14.5px; }
figure { margin: 0; }
figure video { display: block; width: 100%; height: auto; border-radius: 8px; }
figcaption { margin-top: 12px; font-size: 14px; color: var(--muted); line-height: 1.55; }
figcaption b { color: var(--ink); }
.card { background: var(--card); border: 1px solid var(--rule); border-radius: 14px; box-shadow: var(--shadow); }
.pad { padding: 18px; }
@media (min-width: 720px) { .pad { padding: 22px; } }
.card h3.ttl { font-size: 22px; margin-bottom: 4px; }
.card p.sub { font-size: 14px; margin: 0 0 14px; color: var(--muted); }
.note { font-size: 12.5px; color: var(--faint); margin-top: 10px; }
.grid2 { display: grid; gap: 18px; grid-template-columns: 1fr; }
@media (min-width: 900px) { .grid2 { grid-template-columns: 1fr 1fr; } }
.grid2 > * { min-width: 0; }
@media (min-width: 900px) { .grid2.wr { grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr); } }
.mt { margin-top: 26px; }
h3.blk { font-size: 24px; margin-bottom: 6px; }
p.blk { margin: 0 0 12px; font-size: 14.5px; }

/* controls */
.controls { display: flex; flex-wrap: wrap; gap: 8px 12px; align-items: center; padding: 12px 14px; border-top: 1px solid var(--rule);
  background: var(--card); }
.ctl { font: 500 13px var(--sans); color: var(--ink); background: var(--card); border: 1px solid var(--rule); border-radius: 8px;
  padding: 6px 11px; cursor: pointer; display: inline-flex; align-items: center; gap: 6px; }
.ctl:hover { border-color: var(--ink); }
.ctl.on { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.ctl svg { width: 14px; height: 14px; }
.ctl .box { width: 12px; height: 12px; border-radius: 3px; border: 1.5px solid currentColor; display: inline-grid; place-items: center; }
.ctl.on .box::after { content: ""; width: 6px; height: 6px; border-radius: 1.5px; background: currentColor; }
.seg { display: inline-flex; flex-wrap: wrap; border: 1px solid var(--rule); border-radius: 8px; overflow: hidden; }
.seg button { font: 500 12.5px var(--sans); border: 0; background: var(--card); color: var(--muted); padding: 6px 11px; cursor: pointer; }
.seg button.on { background: var(--ink); color: var(--paper); }
.slider { display: inline-flex; align-items: center; gap: 8px; font-size: 13px; color: var(--muted); }
.slider input { width: 110px; accent-color: var(--brand); }
.slider output { font-family: var(--mono); font-size: 12px; color: var(--ink); min-width: 20px; }
.legend { display: flex; flex-wrap: wrap; gap: 6px 14px; font-size: 12px; color: var(--muted); padding: 10px 14px;
  border-top: 1px solid var(--rule); background: var(--card); }
.legend .li { display: inline-flex; align-items: center; gap: 6px; }
.legend i { width: 10px; height: 10px; border-radius: 50%; display: inline-block; }
.legend i.ring { background: #fff; border: 2.5px solid; }
.legend i.line { width: 18px; height: 3px; border-radius: 2px; }
.legend i.band { width: 14px; height: 10px; border-radius: 2px; }

/* selection lab */
.viewer { overflow: hidden; }
.vhead { display: flex; flex-wrap: wrap; gap: 10px 16px; align-items: center; justify-content: space-between; padding: 14px 16px;
  border-bottom: 1px solid var(--rule); }
.vtask { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; font-size: 13.5px; }
.vtask .muted { font-family: var(--serif); font-style: italic; font-size: 15px; }
.vbody { display: grid; grid-template-columns: 1fr; }
@media (min-width: 980px) { .vbody { grid-template-columns: minmax(0, 1fr) 330px; } }
.vstage { position: relative; aspect-ratio: 1 / 1.05; max-height: 760px; background: linear-gradient(180deg, #f7f9fd, #fdfdff 60%);
  border-bottom: 1px solid var(--rule); }
@media (min-width: 980px) { .vstage { border-bottom: 0; border-right: 1px solid var(--rule); } }
@media (max-width: 600px) { .vstage { aspect-ratio: 1 / 1.35; } }
.vstage > canvas { width: 100%; height: 100%; display: block; cursor: pointer; }
.vstage > canvas:focus-visible { outline: 2px solid var(--brand); outline-offset: -2px; }
.vphase { position: absolute; top: 12px; left: 50%; transform: translateX(-50%); font: italic 15px var(--serif); color: #fff;
  padding: 4px 12px; border-radius: 999px; white-space: nowrap; transition: background 0.3s; background: rgba(46, 111, 214, 0.92); }
.vphase.s1 { background: rgba(122, 79, 196, 0.92); }
.vphase.s2 { background: rgba(46, 139, 62, 0.94); }
.vside { padding: 16px; display: flex; flex-direction: column; gap: 14px; background: var(--card); min-width: 0; }
.vlabel { font: 600 11px var(--sans); letter-spacing: 0.14em; text-transform: uppercase; color: var(--muted); margin-bottom: 8px; }
.vlabel .muted { letter-spacing: 0; text-transform: none; font-weight: 400; }
.steps { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 2px; }
.steps li { display: grid; grid-template-columns: 22px 1fr; gap: 8px; padding: 6px 8px; border-radius: 8px; font-size: 13.5px; line-height: 1.45;
  color: var(--faint); cursor: pointer; transition: background 0.2s, color 0.2s; }
.steps li .i { font: 500 11px var(--mono); padding-top: 2px; }
.steps li.done { color: var(--muted); }
.steps li.on { background: var(--coral-tint); color: var(--ink); }
.steps li.on .i { color: var(--coral); }
.eq, .eqcard, .algo { position: relative; }
.eq { min-height: 64px; padding: 12px; border-radius: 10px; background: var(--paper); border: 1px solid var(--rule);
  font-size: 13px; overflow-x: auto; display: grid; align-items: center; }
.eq .katex-display { margin: 0; }
.rank { width: 100%; font-size: 12.5px; }
.rank th, .rank td { padding: 4px 6px; }
.rank td { font-family: var(--mono); font-size: 12px; }
.rank tr.top td { background: var(--pos-tint); }
.rank tr.pick td { background: var(--pick-tint); color: var(--pick); font-weight: 700; }
.rank tr.out td { color: var(--faint); }
.verdict { font-size: 13.5px; color: var(--ink); min-height: 40px; }
.verdict b { color: var(--pick); }

/* method cards */
.pillars { margin-top: 26px; display: grid; gap: 16px; grid-template-columns: 1fr; }
@media (min-width: 820px) { .pillars { grid-template-columns: repeat(2, 1fr); } }
.pillar { position: relative; overflow: hidden; padding: 20px; border-radius: 14px; border: 1px solid var(--rule); background: var(--card);
  box-shadow: var(--shadow); transition: transform 0.25s ease, box-shadow 0.25s ease; min-width: 0; }
.pillar:hover { transform: translateY(-3px); box-shadow: 0 2px 4px rgba(30, 50, 120, 0.06), 0 18px 40px rgba(40, 70, 160, 0.14); }
.pillar .k { font: 600 11px var(--sans); letter-spacing: 0.18em; text-transform: uppercase; }
.pillar h3 { font-size: 22px; margin: 6px 0 8px; }
.pillar p { margin: 0 0 10px; font-size: 14.5px; color: var(--muted); }
.pillar.a { border-top: 3px solid var(--pos); } .pillar.a .k { color: var(--pos); }
.pillar.b { border-top: 3px solid var(--pick); } .pillar.b .k { color: var(--pick); }
.eqcard { padding: 12px 14px; border-radius: 10px; border: 1px solid var(--rule); background: var(--paper); overflow-x: auto; margin: 12px 0; font-size: 13px; }
.eqcard .katex-display { margin: 0.2em 0; }

/* algorithm */
.algo { font: 13px/1.75 var(--mono); color: var(--ink); background: var(--paper); border: 1px solid var(--rule); border-radius: 12px;
  padding: 14px 16px; overflow-x: auto; }
.algo .cap { font: 600 11px var(--sans); letter-spacing: 0.14em; text-transform: uppercase; color: var(--muted); margin-bottom: 8px; }
.algo ol { margin: 0; padding: 0; list-style: none; counter-reset: ln; }
.algo li { counter-increment: ln; display: grid; grid-template-columns: 22px 1fr; gap: 6px; white-space: nowrap; }
.algo li::before { content: counter(ln); color: var(--faint); font-size: 11px; text-align: right; padding-right: 4px; }
.algo li.in1 > span { padding-left: 1.6em; } .algo li.in2 > span { padding-left: 3.2em; }
.algo .kw { color: var(--brand); font-weight: 500; }
.algo .cm { color: var(--faint); }
.algo .inp { white-space: normal; font-family: var(--sans); font-size: 13px; color: var(--muted); margin-bottom: 8px; line-height: 1.55; }

/* results */
.tabs { display: inline-flex; flex-wrap: wrap; gap: 6px; margin-bottom: 16px; }
.tab { font: 500 13px var(--sans); border: 1px solid var(--rule); background: var(--card); color: var(--muted);
  padding: 7px 14px; border-radius: 999px; cursor: pointer; }
.tab.on { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.cmprow { display: flex; flex-wrap: wrap; gap: 8px 12px; align-items: center; margin: -4px 0 14px; font-size: 13px; color: var(--muted); }
.bars { display: grid; gap: 10px; }
.brow { display: grid; grid-template-columns: 96px 1fr 58px; gap: 10px; align-items: center; }
@media (min-width: 720px) { .brow { grid-template-columns: 150px 1fr 70px; } }
.brow .lab { font-size: 13.5px; color: var(--ink); }
.brow .lab small { display: block; font-size: 11px; color: var(--faint); line-height: 1.2; }
.brow.avg { border-top: 1px dashed var(--rule); padding-top: 8px; }
.brow.avg .lab { font-weight: 700; }
.brow .track { position: relative; height: 26px; margin-right: 42px; }
.brow .b { position: absolute; left: 0; height: 11px; border-radius: 3px; width: 0; transition: width 0.7s cubic-bezier(.2,.7,.2,1); }
.brow .b.base { top: 0; background: var(--faint); opacity: 0.55; }
.brow .b.ours { top: 14px; background: linear-gradient(90deg, var(--brand), var(--brand-2)); }
.brow .b span { position: absolute; right: -40px; top: -3px; font: 500 11px var(--mono); color: var(--muted); width: 36px; }
.brow .b.ours span { color: var(--ink); }
.delta { font: 600 12px var(--mono); text-align: right; }
.delta.up { color: var(--exec); } .delta.dn { color: var(--policy); } .delta.flat { color: var(--muted); }
.keyrow { display: flex; flex-wrap: wrap; gap: 6px 16px; font-size: 12px; color: var(--muted); margin-bottom: 12px; }
.keyrow i { display: inline-block; width: 14px; height: 8px; border-radius: 2px; margin-right: 6px; vertical-align: middle; }

.tnums { display: grid; gap: 8px; }
.tn { display: grid; grid-template-columns: 128px 1fr 64px; gap: 10px; align-items: center; font-size: 13px; }
.tn .bar { height: 10px; border-radius: 99px; background: color-mix(in srgb, var(--rule) 55%, transparent); overflow: hidden; }
.tn .bar i { display: block; height: 100%; width: 0; border-radius: 99px; background: var(--faint); opacity: 0.6; transition: width 0.6s cubic-bezier(.2,.7,.2,1); }
.tn.ours .bar i { background: linear-gradient(90deg, var(--brand), var(--brand-2)); opacity: 1; }
.tn.part .bar i { background: var(--brand-2); opacity: 0.7; }
.tn .v { font: 500 12px var(--mono); text-align: right; }
.tn.ours { font-weight: 600; } .tn.ours .v { color: var(--brand); font-weight: 700; }

.tbl-wrap { overflow-x: auto; border: 1px solid var(--rule); border-radius: 12px; background: var(--card); }
table { border-collapse: collapse; width: 100%; font-size: 13.5px; }
th, td { padding: 9px 12px; text-align: center; white-space: nowrap; }
th { font: 600 11px var(--sans); letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); border-bottom: 1px solid var(--rule); }
td:first-child, th:first-child { text-align: left; }
tbody tr { border-bottom: 1px solid color-mix(in srgb, var(--rule) 55%, transparent); }
tbody tr:last-child { border-bottom: 0; }
tr.ours td { background: var(--brand-tint); font-weight: 600; }
tr.ours td:first-child { color: var(--brand); }
tr.avg td { font-weight: 700; border-top: 1px solid var(--rule); }
td.best { font-weight: 700; text-decoration: underline; text-decoration-color: var(--brand-2); text-underline-offset: 3px; }
td sub { font: 500 10px var(--mono); margin-left: 3px; vertical-align: baseline; }
td sub.up { color: var(--exec); } td sub.dn { color: var(--policy); } td sub.flat { color: var(--muted); }
.mini td, .mini th { padding: 8px 10px; }
details { margin-top: 14px; }
details summary { cursor: pointer; font-size: 14px; color: var(--muted); margin-bottom: 10px; }

.aspects { display: grid; gap: 12px; grid-template-columns: 1fr; margin-bottom: 18px; }
@media (min-width: 820px) { .aspects { grid-template-columns: repeat(3, 1fr); } }
.aspect { padding: 16px 18px; border-radius: 12px; border: 1px solid var(--rule); background: var(--card); }
.aspect .k { font: 600 11px var(--sans); letter-spacing: 0.18em; text-transform: uppercase; color: var(--brand); }
.aspect .n { font-family: var(--serif); font-size: 26px; font-weight: 700; line-height: 1.1; margin: 6px 0 6px; }
.aspect .n small { font-size: 14px; font-weight: 500; color: var(--exec); }
.aspect p { margin: 0; font-size: 14px; color: var(--muted); }

.limits { margin-top: 26px; padding: 18px 20px; border-radius: 14px; border: 1px dashed var(--rule); background: color-mix(in srgb, var(--paper) 70%, transparent); }
.limits .kicker { color: var(--muted); }
.limits ul { margin: 8px 0 0; padding-left: 18px; color: var(--muted); font-size: 14.5px; }
.limits li { margin: 4px 0; }

pre.bib { font: 12.5px/1.6 var(--mono); background: var(--card); border: 1px solid var(--rule); border-radius: 12px; padding: 16px;
  overflow-x: auto; margin: 0; position: relative; }
.copy { position: absolute; right: 10px; top: 10px; }
footer { padding: 30px 0 60px; font-size: 13px; color: var(--faint); border-top: 1px solid var(--rule); }
footer a { color: var(--muted); }

.reveal { opacity: 0; transform: translateY(14px); transition: opacity 0.6s ease-out, transform 0.6s ease-out; }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .pillar, .pillar:hover { transition: none; transform: none; }
}