@font-face {
  font-family: "JuliaMono";
  src: url("/fonts/JuliaMono-Regular.woff2") format("woff2");
  font-weight: 400;
  font-display: swap;
}

:root {
  --paper: #f7f7f4;
  --ink: #121318;
  --muted: #5d6169;
  --hair: #d6d7d1;
  --tint: #ecedf3;
  --blue: #1f3be0;
  --blue-dark: #1830b8;
  --red: #b42318;
  --term: #121318;
  --term-ink: #e7e8e3;
  --term-muted: #8b909a;
  --term-key: #9aaeff;
  --term-str: #c9d98f;
  --serif: "STIX Two Text", Georgia, "Times New Roman", serif;
  --mono: "JuliaMono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --wrap: 1160px;
  --gutter: 16px;
}
@media (min-width: 720px) { :root { --gutter: 32px; } }

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 400 19px/1.55 var(--serif);
  font-variant-numeric: lining-nums;
  text-rendering: optimizeLegibility;
}
a { color: var(--blue); text-decoration-thickness: 1px; text-underline-offset: 0.16em; }
a:hover { color: var(--blue-dark); }
:focus-visible { outline: 2px solid var(--blue); outline-offset: 2px; }
code, pre, .mono { font-family: var(--mono); font-size: 0.84em; }
:not(pre) > code { background: var(--tint); padding: 0.05em 0.3em; border-radius: 2px; }
h1, h2, h3 { font-weight: 500; letter-spacing: -0.01em; margin: 0; }
p { margin: 0 0 0.8em; }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 var(--gutter); }
.muted { color: var(--muted); }
.prose { max-width: 38em; }
[hidden] { display: none !important; }

/* ---- header ---- */
.top { display: flex; align-items: center; gap: 12px 28px; flex-wrap: wrap; padding-top: 18px; padding-bottom: 18px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none; font-weight: 600; font-size: 22px; letter-spacing: 0.04em; }
.brand img { width: 17px; height: 28px; }
.nav { display: flex; gap: 22px; flex-wrap: wrap; font-size: 17px; }
.nav a { color: var(--ink); text-decoration: none; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--blue); }
.feed-status { margin-left: auto; font-size: 15px; color: var(--muted); display: flex; align-items: center; gap: 8px; }
.feed-status .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--muted); flex: none; }
.s-live .dot { background: var(--blue); }
.s-offline .dot { background: var(--red); }
.s-offline { color: var(--red); }
@media (max-width: 719px) {
  .feed-status { margin-left: 0; width: 100%; order: 3; }
}
.demo-banner { background: var(--ink); color: var(--paper); font-size: 15px; padding: 8px 0; }

/* ---- hero ---- */
.hero { display: grid; gap: 40px; padding: 48px 0 56px; }
@media (min-width: 980px) { .hero { grid-template-columns: 1.1fr 1fr; gap: 64px; padding: 72px 0 80px; align-items: start; } }
.hero h1 { font-size: clamp(52px, 10.5vw, 104px); line-height: 0.96; letter-spacing: -0.025em; font-weight: 500; }
.qed { display: inline-block; width: 0.42em; height: 0.7em; background: url(/logo.svg) center / contain no-repeat; margin-left: 0.14em; vertical-align: -0.02em; }
.lede { font-size: 22px; line-height: 1.45; margin: 28px 0 32px; max-width: 30em; }
.ca { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 14px; padding: 14px 0; border-top: 1px solid var(--hair); border-bottom: 1px solid var(--hair); }
.ca-label { color: var(--muted); font-size: 16px; }
.ca-value { font-family: var(--mono); font-size: 15px; word-break: break-all; flex: 1 1 16em; }
.ca-value.pending { font-family: var(--serif); font-size: 19px; font-style: italic; color: var(--ink); }
.btn { font: 500 16px/1 var(--serif); background: var(--blue); color: #fff; border: 0; border-radius: 3px; padding: 10px 16px; cursor: pointer; text-decoration: none; display: inline-block; }
.btn:hover { background: var(--blue-dark); color: #fff; }
.links { display: flex; gap: 22px; flex-wrap: wrap; margin-top: 18px; font-size: 18px; }

/* ---- live terminal pane ---- */
.term { background: var(--term); color: var(--term-ink); border-radius: 4px; padding: 18px 20px 20px; min-width: 0; }
.term-head { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; font-size: 15px; color: var(--term-muted); }
.term-title { font-size: 21px; line-height: 1.3; margin: 8px 0 4px; color: var(--term-ink); }
.term-title a { color: inherit; text-decoration-color: var(--term-muted); }
.term-meta { font-size: 15px; color: var(--term-muted); display: flex; gap: 18px; flex-wrap: wrap; }
.term pre { margin: 14px 0 0; font-size: 13px; line-height: 1.6; white-space: pre-wrap; word-break: break-word; color: var(--term-ink); max-height: 260px; overflow: auto; }
.term pre .dim { color: var(--term-muted); }
.caret { display: inline-block; width: 0.55em; height: 1.05em; background: var(--term-key); vertical-align: -0.2em; animation: blink 1.1s steps(1) infinite; }
@keyframes blink { 50% { opacity: 0; } }

/* ---- tally: a booktabs table of four live numbers ---- */
.tally { width: 100%; border-collapse: collapse; border-top: 2px solid var(--ink); border-bottom: 2px solid var(--ink); table-layout: fixed; }
.tally td { padding: 18px 12px 18px 0; vertical-align: top; }
.tally b { display: block; font-weight: 500; font-size: clamp(34px, 6vw, 56px); line-height: 1; font-variant-numeric: lining-nums tabular-nums; letter-spacing: -0.02em; }
.tally span { display: block; margin-top: 8px; font-size: 16px; color: var(--muted); line-height: 1.3; }
@media (max-width: 719px) {
  .tally, .tally tbody, .tally tr { display: block; }
  .tally tr { display: grid; grid-template-columns: 1fr 1fr; }
  .tally td { border-bottom: 1px solid var(--hair); }
  .tally td:nth-child(n+3) { border-bottom: 0; }
}

/* ---- sections ---- */
.sec { padding: 72px 0 0; }
.sec h2 { font-size: clamp(32px, 5vw, 46px); line-height: 1.1; margin-bottom: 24px; }
.sec-head { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; flex-wrap: wrap; margin-bottom: 20px; }
.sec-head h2 { margin: 0; }

/* latest events */
.events { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--ink); }
.events li { display: grid; grid-template-columns: 5.5em 1fr; gap: 4px 16px; padding: 11px 0; border-bottom: 1px solid var(--hair); }
.events time { color: var(--muted); font-size: 16px; font-variant-numeric: tabular-nums; padding-top: 2px; }
.events .ev { display: flex; gap: 10px; align-items: baseline; min-width: 0; }
.events .ev .g { flex: none; }
.events a { color: var(--ink); text-decoration: none; }
.events a:hover { color: var(--blue); }
.events li.fresh { animation: fresh 2.4s ease-out; }
@keyframes fresh { from { background: var(--tint); } to { background: transparent; } }
.empty { color: var(--muted); font-style: italic; padding: 14px 0; }

/* how it works */
.steps { list-style: none; counter-reset: step; margin: 0; padding: 0; display: grid; gap: 28px; }
@media (min-width: 860px) { .steps { grid-template-columns: repeat(3, 1fr); gap: 40px; } }
.steps li { counter-increment: step; border-top: 2px solid var(--ink); padding-top: 14px; }
.steps li::before { content: counter(step); display: block; font-size: 44px; line-height: 1; color: var(--blue); margin-bottom: 14px; }
.steps h3 { font-size: 24px; margin-bottom: 8px; }
.steps p { color: var(--ink); }

/* where NEAR comes in */
.near { display: grid; gap: 0; border-top: 2px solid var(--ink); }
.near-row { display: grid; gap: 8px 48px; padding: 24px 0; border-bottom: 1px solid var(--hair); }
@media (min-width: 860px) { .near-row { grid-template-columns: 0.9fr 1.1fr; } }
.near-row h3 { font-size: clamp(28px, 4vw, 38px); line-height: 1.1; }
.near-row p { margin: 0 0 0.5em; }
.near-row .src { font-size: 16px; color: var(--muted); }
.live-note { border-left: 3px solid var(--blue); padding-left: 12px; }

/* verify */
.code { background: var(--term); color: var(--term-ink); border-radius: 4px; padding: 16px 18px; overflow: auto; font-size: 13.5px; line-height: 1.65; margin: 0; tab-size: 2; }
.code .l-k { color: var(--term-key); }
.code .l-c { color: var(--term-muted); font-style: italic; }
.code .l-s { color: var(--term-str); }
.code .l-a { color: var(--term-muted); }
.code .l-x { color: #ff8f80; }
.code .prompt { color: var(--term-muted); user-select: none; }
.cmd-wrap { position: relative; }
.cmd-wrap .btn { position: absolute; top: 10px; right: 10px; padding: 7px 11px; font-size: 14px; }

/* faq */
.faq { border-top: 2px solid var(--ink); }
.faq details { border-bottom: 1px solid var(--hair); padding: 0; }
.faq summary { cursor: pointer; padding: 16px 0; font-size: 22px; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--blue); font-size: 26px; line-height: 1; }
.faq details[open] summary::after { content: "\2212"; }
.faq details > div { padding: 0 0 18px; max-width: 40em; }

/* footer */
.foot { margin-top: 96px; padding-bottom: 40px; font-size: 16px; color: var(--muted); }
.foot-in { border-top: 1px solid var(--ink); padding-top: 28px; }
.foot p { margin: 0 0 6px; }

/* ---- state glyphs: a tombstone family ---- */
.g { display: inline-block; width: 0.62em; height: 0.72em; vertical-align: -0.05em; margin-right: 0.45em; flex: none; }
.g-proved { background: var(--blue); }
.g-running { background: var(--blue); width: 0.36em; margin-right: 0.71em; animation: blink 1.1s steps(1) infinite; }
.g-queued { border: 1.5px solid var(--muted); }
.g-gave_up { border: 1.5px solid var(--muted); background: linear-gradient(to top right, transparent 46%, var(--muted) 46%, var(--muted) 54%, transparent 54%); }
.g-error { background: var(--red); }
.g.still { animation: none; }
.term .g-queued, .term .g-gave_up { border-color: var(--term-muted); }

/* ---- problems board ---- */
.filters { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 18px; }
.filters button { font: 400 17px/1 var(--serif); background: none; border: 1px solid var(--hair); color: var(--ink); padding: 9px 14px; border-radius: 3px; cursor: pointer; }
.filters button[aria-pressed="true"] { background: var(--ink); border-color: var(--ink); color: var(--paper); }
.filters button span { color: var(--muted); margin-left: 4px; }
.filters button[aria-pressed="true"] span { color: #b9bcc4; }
.board { width: 100%; border-collapse: collapse; border-top: 2px solid var(--ink); border-bottom: 2px solid var(--ink); font-variant-numeric: tabular-nums; }
.board th { text-align: left; font-weight: 400; color: var(--muted); font-size: 16px; padding: 10px 12px 10px 0; border-bottom: 1px solid var(--ink); white-space: nowrap; }
.board td { padding: 12px 12px 12px 0; border-bottom: 1px solid var(--hair); vertical-align: baseline; }
.board tr:last-child td { border-bottom: 0; }
.board .num, .board .n { text-align: right; white-space: nowrap; }
.board .no { width: 4.5em; color: var(--muted); white-space: nowrap; }
.board td.title a { color: var(--ink); text-decoration: none; }
.board tbody tr { cursor: pointer; }
.board tbody tr:hover td { background: var(--tint); }
.board tbody tr:hover td.title a { color: var(--blue); }
.board .st { white-space: nowrap; }
.board .pz { width: 4.5em; white-space: nowrap; }
.up-open { color: var(--ink); }
.up-solved { color: var(--muted); }
@media (max-width: 719px) {
  .board thead { display: none; }
  .board, .board tbody { display: block; }
  .board tr { display: grid; grid-template-columns: 3.2em 1fr auto auto; gap: 2px 10px; padding: 12px 0; border-bottom: 1px solid var(--hair); }
  .board tr:last-child { border-bottom: 0; }
  .board td { padding: 0; border: 0; }
  .board td.empty { grid-column: 1 / -1; }
  .board .no { grid-row: 1; grid-column: 1; width: auto; }
  .board td.title { grid-row: 1; grid-column: 2 / 5; }
  .board .pz { grid-row: 2; grid-column: 3; font-size: 15px; }
  .board .up { grid-row: 2; grid-column: 1; font-size: 15px; }
  .board .st { padding-left: 0; }
  .board .st { grid-row: 2; grid-column: 2; font-size: 15px; }
  .board .cost { grid-row: 2; grid-column: 4; font-size: 15px; }
  .board .turns { display: none; }
}

/* ---- problem page ---- */
.crumb { font-size: 17px; margin: 28px 0 20px; }
.prob-head h1 { font-size: clamp(40px, 7vw, 72px); line-height: 1.02; letter-spacing: -0.02em; }
.prob-title { font-size: 24px; margin: 12px 0 0; max-width: 34em; }
.facts { display: flex; flex-wrap: wrap; gap: 6px 28px; margin: 22px 0 0; padding: 12px 0; border-top: 1px solid var(--ink); border-bottom: 1px solid var(--hair); font-size: 17px; }
.facts div { display: flex; gap: 8px; align-items: baseline; }
.facts dt { color: var(--muted); }
.facts dd { margin: 0; font-variant-numeric: tabular-nums; }
.statement { font-size: 21px; line-height: 1.6; max-width: 36em; }
.statement .katex-display { margin: 0.6em 0; overflow-x: auto; overflow-y: hidden; }
.refs { display: flex; gap: 22px; flex-wrap: wrap; margin-top: 8px; }
.sub { padding-top: 48px; }
.sub h2 { font-size: 30px; margin-bottom: 16px; }
.verified { display: grid; grid-template-columns: auto 1fr; gap: 22px; align-items: start; padding: 22px 0; border-top: 2px solid var(--blue); border-bottom: 1px solid var(--hair); margin-bottom: 20px; }
.verified .qed { width: 36px; height: 60px; margin: 4px 0 0; }
.verified h2 { margin: 0 0 8px; color: var(--blue); }
.verified p { margin: 0 0 8px; max-width: 38em; }
.verified .axioms { margin-bottom: 10px; }
.axioms { display: flex; flex-wrap: wrap; gap: 8px; margin: 6px 0 0; padding: 0; list-style: none; }
.axioms li { font-family: var(--mono); font-size: 14px; background: var(--tint); padding: 3px 8px; border-radius: 2px; }
.axioms li.bad { background: #fbe4e1; color: var(--red); }
.warn { border-left: 3px solid var(--red); padding-left: 12px; }
.note { border-left: 3px solid var(--ink); padding-left: 12px; max-width: 40em; }
.row-actions { display: flex; gap: 18px; align-items: center; flex-wrap: wrap; margin: 0 0 14px; }
.log pre { max-height: 420px; }
.not-found { padding: 64px 0; }
@media (max-width: 719px) { .events li { grid-template-columns: 4.2em 1fr; gap: 4px 10px; } }
.ca-label { flex-basis: 100%; }
@media (max-width: 719px) { .top { gap: 10px 16px; } .nav { gap: 14px; font-size: 16px; } }

/* Erdős prize chip */
.prize { display: inline-block; font-size: 0.85em; line-height: 1.35; padding: 0 0.45em; border-radius: 2px; background: #e3e7fb; color: var(--blue-dark); font-variant-numeric: lining-nums tabular-nums; white-space: nowrap; vertical-align: 0.08em; }
.prize.closed { background: var(--tint); color: var(--muted); }
.term .prize { background: #26306a; color: #d7ddff; }
.bounty-line { font-size: clamp(22px, 2.4vw, 27px); line-height: 1.38; margin: 28px 0 14px; max-width: 26em; }
.lede.second { font-size: 19px; color: var(--muted); margin: 0 0 8px; }
.src-line { font-size: 15px; color: var(--muted); margin: 0 0 28px; }
.tags { color: var(--muted); }
.prob-prize { margin: 14px 0 0; font-size: 17px; max-width: 40em; }
/* Feed titles and statements can contain long unbroken URLs. */
.board td.title, .prob-title, .statement, .term-title, .events .ev { overflow-wrap: anywhere; }
/* A formula wider than a phone (one long set literal, say) scrolls inside its cell instead of widening the page. */
.board td.title { min-width: 0; overflow-x: auto; overflow-y: hidden; }