/* ∵ causari — one design system for every page.
   Four values (ink, paper, graphite, mist); dark and light are the same values swapped.
   Sans for reading, monospace for code, commands, data and short labels only.
   Three components: the terminal card, the data table, the proof card. No colour on a number. */

:root {
  --ink: #0b0d10;
  --paper: #f5f4ef;
  --graphite: #3b4252;
  --mist: #9aa3ad;

  /* light: ink on paper. fg 17.7:1, fg-2 9.1:1, fg-3 5.5:1 */
  --bg: var(--paper);
  --fg: var(--ink);
  --fg-2: var(--graphite);
  --fg-3: #5b6470;
  --line: rgba(11, 13, 16, 0.16);
  --line-2: rgba(11, 13, 16, 0.07);
  --panel: rgba(11, 13, 16, 0.035);
  --code-bg: #0b0d10;
  --code-fg: #f5f4ef;
  --code-dim: #9aa3ad;          /* 7.6:1 on the terminal */
  --code-line: rgba(245, 244, 239, 0.08);

  --mono: ui-monospace, "JetBrains Mono", "SF Mono", "Cascadia Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, "Helvetica Neue", Arial, sans-serif;

  /* type scale */
  --fs-body: 17px;
  --fs-h1: clamp(2.1rem, 1.35rem + 2.6vw, 3.1rem);
  --fs-h2: clamp(1.5rem, 1.15rem + 1.2vw, 2rem);
  --fs-h3: 1.2rem;
  --fs-lede: 1.15rem;
  --fs-small: 0.9rem;
  --fs-label: 0.8rem;           /* the smallest monospace on the site */
  --fs-code: 0.9rem;

  /* spacing scale */
  --s-1: 0.5rem;
  --s-2: 1rem;
  --s-3: 1.5rem;
  --s-4: 2rem;
  --s-5: 3rem;
  --s-6: 5rem;

  --prose: 70ch;
  --maxw: 1080px;
  --radius: 12px;
}
@media (prefers-color-scheme: dark) {
  :root {
    /* dark: paper on ink. fg 17.7:1, fg-2 12.1:1, fg-3 7.6:1 */
    --bg: var(--ink);
    --fg: var(--paper);
    --fg-2: #c7ccd3;
    --fg-3: var(--mist);
    --line: rgba(245, 244, 239, 0.18);
    --line-2: rgba(245, 244, 239, 0.08);
    --panel: rgba(245, 244, 239, 0.045);
    --code-bg: #111418;
    --code-line: rgba(245, 244, 239, 0.14);
  }
}
html[data-theme="dark"] {
  --bg: var(--ink); --fg: var(--paper); --fg-2: #c7ccd3; --fg-3: var(--mist);
  --line: rgba(245, 244, 239, 0.18); --line-2: rgba(245, 244, 239, 0.08);
  --panel: rgba(245, 244, 239, 0.045); --code-bg: #111418; --code-line: rgba(245, 244, 239, 0.14);
}
html[data-theme="light"] {
  --bg: var(--paper); --fg: var(--ink); --fg-2: var(--graphite); --fg-3: #5b6470;
  --line: rgba(11, 13, 16, 0.16); --line-2: rgba(11, 13, 16, 0.07);
  --panel: rgba(11, 13, 16, 0.035); --code-bg: #0b0d10; --code-line: rgba(245, 244, 239, 0.08);
}

/* ------------------------------------------------------------------ base */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: var(--fs-body);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  overflow-wrap: break-word;
}
@media (max-width: 640px) { :root { --fs-body: 16px; --fs-lede: 1.08rem; } }

h1, h2, h3 { font-family: var(--sans); font-weight: 600; letter-spacing: -0.015em; margin: 0 0 var(--s-2); text-wrap: balance; }
h1 { font-size: var(--fs-h1); line-height: 1.12; letter-spacing: -0.02em; }
h2 { font-size: var(--fs-h2); line-height: 1.18; }
h3 { font-size: var(--fs-h3); line-height: 1.3; margin-bottom: var(--s-1); }
p, ul, ol, dl { margin: 0 0 var(--s-2); }
li { margin: 0.3rem 0; }
strong { font-weight: 600; }
a { color: inherit; text-decoration: underline; text-decoration-color: var(--mist); text-underline-offset: 3px; text-decoration-thickness: 1px; }
a:hover { text-decoration-color: var(--fg); }
img { max-width: 100%; height: auto; }

code, pre, kbd, samp { font-family: var(--mono); }
code { font-size: 0.92em; }
p code, li code, td code, dd code, label code { background: var(--panel); padding: 0.05em 0.35em; border-radius: 4px; }
.muted { color: var(--fg-3); }
.small { font-size: var(--fs-small); }
.prose { max-width: var(--prose); }
.prose > :last-child { margin-bottom: 0; }

.eyebrow { font-family: var(--mono); font-size: var(--fs-label); color: var(--fg-3); letter-spacing: 0.02em; margin: 0 0 var(--s-2); }
.eyebrow a { text-decoration-color: var(--line); }
.lede { font-size: var(--fs-lede); color: var(--fg-2); line-height: 1.5; }

:focus-visible { outline: 2px solid var(--fg); outline-offset: 2px; }
.skip-link { position: absolute; left: -999px; top: 0; background: var(--fg); color: var(--bg); padding: 0.5rem 1rem; }
.skip-link:focus { left: 1rem; top: 1rem; z-index: 100; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 1.25rem; }
@media (max-width: 640px) { .container { padding: 0 1rem; } }

/* ------------------------------------------------------------------ buttons */
.btn {
  display: inline-flex; align-items: center; gap: 0.4rem;
  font-family: var(--sans); font-size: 0.95rem; font-weight: 600; line-height: 1;
  color: var(--fg); background: transparent; border: 1px solid var(--fg); border-radius: 8px;
  padding: 0.7rem 1.1rem; cursor: pointer; text-decoration: none; white-space: nowrap;
}
.btn:hover { background: var(--fg); color: var(--bg); }
.btn-primary { background: var(--fg); color: var(--bg); }
.btn-primary:hover { background: var(--fg-2); border-color: var(--fg-2); }
.btn-quiet { border-color: var(--line); color: var(--fg-2); font-weight: 500; }
.btn-quiet:hover { border-color: var(--fg); background: transparent; color: var(--fg); }

/* ------------------------------------------------------------------ nav */
.nav { border-bottom: 1px solid var(--line-2); position: sticky; top: 0; background: var(--bg); z-index: 20; }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; gap: var(--s-2); }
.brand { display: inline-flex; align-items: center; gap: 0.7rem; text-decoration: none; font-family: var(--mono); font-size: 1.3rem; font-weight: 600; }
.brand img, .brand svg { width: 34px; height: 34px; display: block; }
.brand-name { letter-spacing: -0.02em; }
.nav-links { display: flex; align-items: center; gap: 1.4rem; font-family: var(--mono); font-size: 0.88rem; }
.nav-links a { text-decoration: none; color: var(--fg-2); padding: 0.3rem 0; }
.nav-links a:hover, .nav-links a[aria-current] { color: var(--fg); }
.nav-links a[aria-current] { box-shadow: inset 0 -2px 0 var(--fg); }
.theme-toggle { background: none; border: 0; color: var(--fg-3); font-size: 1.1rem; cursor: pointer; padding: 0.2rem 0.3rem; line-height: 1; }
.theme-toggle:hover { color: var(--fg); }

/* the mark is ink on paper, paper on ink; swap by theme */
.mark-dark { display: none; }
@media (prefers-color-scheme: dark) { .mark-light { display: none; } .mark-dark { display: block; } }
html[data-theme="dark"] .mark-light { display: none; }
html[data-theme="dark"] .mark-dark { display: block; }
html[data-theme="light"] .mark-light { display: block; }
html[data-theme="light"] .mark-dark { display: none; }
@media (max-width: 640px) {
  .nav-inner { height: 56px; }
  .nav-links { gap: 1rem; font-size: var(--fs-label); }
  .nav-links a.hide-sm { display: none; }
  .brand img { width: 30px; height: 30px; }
  .brand { font-size: 1.1rem; gap: 0.55rem; }
  /* on a phone the mark stands alone; the link keeps its aria-label */
  .brand-name { display: none; }
}

/* ------------------------------------------------------------------ 1. terminal card */
pre {
  background: var(--code-bg);
  color: var(--code-fg);
  border: 1px solid var(--code-line);
  border-radius: var(--radius);
  padding: 1.1rem 1.3rem;
  margin: 0;
  overflow-x: auto;
  font-size: var(--fs-code);
  line-height: 1.6;
  tab-size: 4;
}
pre code { background: none; padding: 0; font-size: inherit; }
pre .dim { color: var(--code-dim); }
pre .ok { color: var(--code-fg); font-weight: 600; }
.term { position: relative; min-width: 0; display: flex; flex-direction: column; }
.term pre { flex: 1; }
.term-hero pre { font-size: clamp(0.86rem, 0.72rem + 0.45vw, 1rem); padding: 1.35rem 1.6rem; }
/* optional title bar: a label and the copy button, so the button never sits on a command */
.term-head {
  display: flex; align-items: center; justify-content: space-between; gap: var(--s-2);
  background: var(--code-bg); color: var(--code-dim); border: 1px solid var(--code-line); border-bottom: 0;
  border-radius: var(--radius) var(--radius) 0 0; padding: 0.55rem 1.1rem 0.55rem 1.3rem;
  font-family: var(--mono); font-size: var(--fs-label);
}
.term-head + pre { border-radius: 0 0 var(--radius) var(--radius); padding-top: 0.9rem; }
button.copy {
  font-family: var(--mono); font-size: var(--fs-label); color: var(--code-dim); background: var(--code-bg);
  border: 1px solid rgba(154, 163, 173, 0.4); border-radius: 6px; padding: 0.25rem 0.6rem; cursor: pointer;
}
button.copy:hover { color: var(--code-fg); border-color: var(--code-fg); }
button.copy:focus-visible { outline-color: var(--code-fg); }

/* ------------------------------------------------------------------ 2. data table */
.tbl-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; margin: var(--s-2) 0 var(--s-3); max-width: 100%; }
/* a wide table may leave the prose column on large screens, centred, so ten columns fit without scrolling */
@media (min-width: 1160px) {
  .tbl-scroll.wide { width: min(1320px, calc(100vw - 3rem)); max-width: none; position: relative; left: 50%; transform: translateX(-50%); }
}
table.tbl, table.lb-table { width: 100%; border-collapse: collapse; font-size: 0.95rem; line-height: 1.4; }
table.tbl th, table.lb-table th {
  font-family: var(--mono); font-weight: 500; font-size: var(--fs-label); color: var(--fg-3);
  text-align: left; padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--line); white-space: nowrap; vertical-align: bottom;
}
table.tbl td, table.lb-table td { padding: 0.7rem 0.9rem; border-bottom: 1px solid var(--line-2); vertical-align: top; }
table.tbl td:first-child, table.lb-table td:first-child { font-weight: 500; }
table.is-num td:first-child, table.lb-table td:first-child { white-space: nowrap; }
table.tbl td code, table.lb-table td code { white-space: nowrap; }
/* numeric tables: every column but the first (and any .txt column) is a number, right-aligned, tabular */
table.is-num th:not(:first-child):not(.txt), table.is-num td:not(:first-child):not(.txt),
table.lb-table th:not(:first-child):not(.txt), table.lb-table td:not(:first-child):not(.txt) {
  text-align: right; font-family: var(--mono); font-size: 0.88rem; font-variant-numeric: tabular-nums; white-space: nowrap;
}
table.is-num th:not(:first-child):not(.txt), table.lb-table th:not(:first-child):not(.txt) { font-size: var(--fs-label); }
table td.txt, table th.txt { text-align: left; }
.rp-num { text-decoration: none; }
.rp-num:hover { text-decoration: underline; }
.lb-none { color: var(--fg-3); }

/* ------------------------------------------------------------------ 3. proof card */
.proof { border: 1px solid var(--line); border-radius: var(--radius); padding: var(--s-3); background: var(--panel); min-width: 0; }
.proof h3 { margin: 0 0 var(--s-1); }
.proof p, .proof li { color: var(--fg-2); }
.proof p:last-child, .proof ul:last-child { margin-bottom: 0; }
.proof pre { margin-top: var(--s-2); font-size: 0.86rem; }
.proof pre:last-child { margin-bottom: 0; }
.proof-grid { display: grid; gap: var(--s-3); grid-template-columns: repeat(auto-fit, minmax(min(100%, 300px), 1fr)); }

/* ------------------------------------------------------------------ sections and screens */
.section, .screen { padding: var(--s-6) 0; border-top: 1px solid var(--line-2); }
.section:first-of-type { border-top: 0; }
.section-head { max-width: var(--prose); margin-bottom: var(--s-4); }
.section-head > :last-child { margin-bottom: 0; }
.section-head p.muted { margin-bottom: 0; }
.section .section-head h1 { margin-bottom: var(--s-2); }
.grid { display: grid; gap: var(--s-3); }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 300px), 1fr)); }

/* one idea per screen: text left, the command right */
.screen-grid { display: grid; gap: var(--s-4); grid-template-columns: minmax(0, 1fr); align-items: start; }
@media (min-width: 900px) { .screen-grid { grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: var(--s-5); } }
.screen-text > :last-child { margin-bottom: 0; }
.screen-text .actions { display: flex; flex-wrap: wrap; gap: var(--s-1) var(--s-2); margin-top: var(--s-3); align-items: center; }
.screen-more { margin-top: var(--s-4); }
@media (max-width: 640px) { .section, .screen { padding: var(--s-5) 0; } }

/* hero */
.hero { padding: var(--s-6) 0 var(--s-5); }
.hero h1 { max-width: 20ch; }
.hero .lede { max-width: 60ch; margin-top: var(--s-2); }
.hero .term { margin-top: var(--s-4); max-width: 920px; }
.hero-meta { margin: var(--s-3) 0 0; font-family: var(--mono); font-size: var(--fs-label); line-height: 1.7; color: var(--fg-3); }
@media (max-width: 640px) {
  .hero { padding: var(--s-5) 0 var(--s-4); }
  pre { font-size: 0.82rem; padding: 0.9rem 1rem; }
  .term-hero pre { padding: 1rem 1.1rem; }
  .term-head { padding-left: 1rem; padding-right: 0.8rem; }
}

/* install strip: four short terminals */
.strip { display: grid; gap: var(--s-2); grid-template-columns: repeat(auto-fit, minmax(min(100%, 400px), 1fr)); }
.strip pre { font-size: 0.86rem; padding: 0.9rem 1.3rem 1rem; }

/* ------------------------------------------------------------------ footer */
.footer { border-top: 1px solid var(--line); padding: var(--s-4) 0 var(--s-5); color: var(--fg-3); font-size: var(--fs-small); }
.foot-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--s-2); }
.foot-bottom p { margin: 0; }
.foot-bottom .foot-note { flex-basis: 100%; color: var(--fg-3); }
.facts { list-style: none; padding: 0; margin: var(--s-3) 0; }
.facts li { padding: var(--s-2) 0; border-top: 1px solid var(--line); line-height: 1.55; }
.facts li:last-child { border-bottom: 1px solid var(--line); }
.facts .check { display: block; margin-top: 0.4rem; font-size: var(--fs-small); color: var(--fg-3); }
.facts [data-fact] { font-variant-numeric: tabular-nums; }

/* ------------------------------------------------------------------ article (method) */
.article { max-width: var(--prose); margin: 0 auto; padding: var(--s-5) 1.25rem var(--s-6); }
.article h1 { margin-bottom: var(--s-1); }
.article h2 { margin-top: var(--s-5); }
.article h2 .no { font-family: var(--mono); font-weight: 500; font-size: 0.8em; color: var(--fg-3); margin-right: 0.5rem; }
.article pre { margin: var(--s-2) 0 var(--s-3); }
.article .proof-grid { margin: var(--s-3) 0; grid-template-columns: 1fr; }
.article .version { color: var(--fg-3); font-size: var(--fs-small); margin-bottom: var(--s-4); }
@media (max-width: 640px) { .article { padding: var(--s-4) 1rem var(--s-5); } }

/* ------------------------------------------------------------------ report pages (scripts/survival_report.py) */
.rp-meta { font-size: var(--fs-small); color: var(--fg-3); }
.rp-meta a, .rp-doi { color: var(--fg-2); }
.rp-doi { font-family: var(--mono); font-size: 0.85em; border: 1px solid var(--line); border-radius: 4px; padding: 0.1rem 0.45rem; text-decoration: none; }
.rp-latest { margin: 0 0 var(--s-3); font-size: var(--fs-lede); color: var(--fg-2); max-width: var(--prose); }
.rp-strip { display: grid; gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; margin: 0 0 var(--s-4); grid-template-columns: repeat(2, 1fr); }
@media (min-width: 700px) { .rp-strip { grid-template-columns: repeat(3, 1fr); } }
.rp-stat { display: block; background: var(--bg); padding: var(--s-2) 1.1rem; text-decoration: none; min-width: 0; }
.rp-stat:hover { background: var(--panel); }
.rp-stat .n { display: block; font-family: var(--mono); font-size: clamp(1.4rem, 1rem + 1vw, 1.8rem); font-weight: 500; letter-spacing: -0.02em; line-height: 1.1; font-variant-numeric: tabular-nums; }
.rp-stat .l { display: block; font-size: var(--fs-small); color: var(--fg-3); margin-top: 0.4rem; line-height: 1.35; }
.rp-card { display: block; width: 100%; height: auto; border: 1px solid var(--line); border-radius: var(--radius); margin: 0 0 var(--s-4); }
.rp-section { margin-top: var(--s-4); }
.rp-section > p.muted { max-width: var(--prose); }
.rp-list li { margin: 0.4rem 0; }
.rp-cite { margin-top: var(--s-4); font-size: var(--fs-small); color: var(--fg-3); }
.rp-positioning { margin-top: var(--s-5); }
.rp-positioning p { max-width: var(--prose); }
/* repository pages (/r/): a one-colour sparkline in the text colour, badges at their natural 20 px */
.spark { display: block; width: 160px; max-width: 100%; height: 36px; color: var(--fg); margin: 0 0 var(--s-1); }
.rp-badges { display: flex; flex-wrap: wrap; gap: var(--s-1) var(--s-2); align-items: center; margin: 0 0 var(--s-2); }
.rp-badges img { height: 20px; width: auto; max-width: 100%; }
.section-head h1 a { text-decoration-thickness: 1px; text-underline-offset: 6px; }

/* ------------------------------------------------------------------ verify page: the verdict is text; no colour carries meaning */
.vf-grid { display: grid; gap: var(--s-3); grid-template-columns: minmax(0, 1fr); align-items: start; margin-top: var(--s-4); }
@media (min-width: 900px) { .vf-grid { grid-template-columns: minmax(0, 3fr) minmax(0, 2fr); } }
.vf-drop { border: 2px dashed var(--line); border-radius: 16px; padding: var(--s-3); background: var(--panel); min-width: 0; }
.vf-drop.is-over { border-style: solid; border-color: var(--fg); }
.vf-drop .vf-label { display: block; font-size: 1rem; color: var(--fg-2); margin-bottom: var(--s-2); }
.vf-drop textarea {
  display: block; width: 100%; min-height: 280px; resize: vertical; font-family: var(--mono); font-size: 0.85rem; line-height: 1.5;
  color: var(--fg); background: var(--bg); border: 1px solid var(--line); border-radius: 10px; padding: 0.85rem 1rem;
}
.vf-drop textarea::placeholder { color: var(--fg-3); }
.vf-drop textarea:focus { outline: 2px solid var(--fg); outline-offset: 1px; }
.vf-actions { display: flex; flex-wrap: wrap; align-items: center; gap: var(--s-1) var(--s-2); margin-top: var(--s-2); }
@media (max-width: 640px) {
  .vf-drop { padding: var(--s-2); }
  .vf-actions .btn { padding: 0.65rem 0.85rem; font-size: 0.9rem; }
}
.vf-actions input[type="file"] { position: absolute; width: 1px; height: 1px; opacity: 0; overflow: hidden; }
.vf-actions input[type="file"]:focus-visible + label { outline: 2px solid var(--fg); outline-offset: 2px; }
.vf-filename { font-size: var(--fs-small); color: var(--fg-3); overflow-wrap: anywhere; }
.vf-sample { margin-top: var(--s-3); padding-top: var(--s-2); border-top: 1px dashed var(--line); }
.vf-sample .vf-hint { flex-basis: 100%; margin: 0; font-size: var(--fs-small); color: var(--fg-3); }
.vf-result { min-width: 0; }
.vf-result .vf-empty { margin: 0; }
.vf-result .vf-empty ol { margin: var(--s-2) 0 0; padding-left: 1.3rem; }
.vf-result.has-result .vf-empty { display: none; }
.vf-result:not(.has-result) .vf-verdict { display: none; }
.vf-verdict { font-family: var(--sans); font-size: 1.35rem; font-weight: 600; line-height: 1.3; margin: 0 0 var(--s-2); overflow-wrap: anywhere; color: var(--fg); }
.vf-verdict[data-valid="false"] { text-decoration: underline; text-decoration-color: var(--mist); text-decoration-thickness: 2px; }
.vf-states { display: grid; grid-template-columns: max-content minmax(0, 1fr); gap: 0.4rem 1rem; font-size: 0.95rem; margin: 0 0 var(--s-2); }
.vf-states dt { font-family: var(--mono); color: var(--fg-3); font-size: var(--fs-label); padding-top: 0.2em; }
.vf-states dd { margin: 0; overflow-wrap: anywhere; color: var(--fg); }
.vf-states dd code { font-size: 0.85em; }
@media (max-width: 480px) { .vf-states { grid-template-columns: 1fr; gap: 0.1rem 0; } .vf-states dd { margin-bottom: 0.5rem; } }
.vf-result .tbl-scroll { margin: var(--s-2) 0; }
.vf-result .tbl-scroll:has(> table[hidden]) { display: none; }
#vf-means { font-size: var(--fs-small); color: var(--fg-2); }
.vf-steps { list-style: none; padding: 0; margin: var(--s-2) 0 0; font-family: var(--mono); font-size: var(--fs-label); border-top: 1px solid var(--line-2); }
.vf-steps:empty { display: none; }
.vf-steps li { display: grid; grid-template-columns: 1.4em minmax(0, 1fr); gap: 0.5rem; padding: 0.4rem 0; border-bottom: 1px solid var(--line-2); }
.vf-steps li.hdr { color: var(--fg-3); padding-top: 0.85rem; }
.vf-steps li.fail { font-weight: 600; }
.vf-steps .det { color: var(--fg-3); display: block; overflow-wrap: anywhere; font-weight: 400; }
.vf-unsupported[hidden] { display: none; }
.vf-unsupported { margin-top: var(--s-3); }