/* Trigon: a static page. No build step, no fonts or scripts from any other host. */

/* ---------------------------------------------------------------------------------------------
   Tokens. Neutrals are a cool slate (hue near 215). Blue is the structural colour, as it is for
   the CLI's labels; cyan marks data; green, yellow and red belong to the outcomes and to nothing
   else, as in crates/trigon/src/style.rs.
   --------------------------------------------------------------------------------------------- */
:root {
  color-scheme: light dark;

  --bg: #f4f6f9;
  --panel: #e8ecf1;
  --panel-bar: #dde3ea;
  --ink: #111923;
  --ink-2: #36414e;
  --muted: #55616e;
  --rule: #cfd6df;
  --rule-strong: #77838f;
  --accent: #1c4ea3;
  --accent-hover: #163f86;
  --accent-ink: #ffffff;
  --ident: #0a6273;
  --ok: #17703a;
  --warn: #7f5200;
  --bad: #b3261e;
  --focus: #1c4ea3;

  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", "Noto Sans",
    "Liberation Sans", Arial, sans-serif;
  --mono: ui-monospace, "SFMono-Regular", "SF Mono", "Cascadia Mono", "Segoe UI Mono",
    "DejaVu Sans Mono", Menlo, Consolas, "Liberation Mono", monospace;

  /* One scale, ratio 1.25 from a 17px body. Nothing sets a size outside it. */
  --fs-xs: 0.8125rem;
  --fs-sm: 0.875rem;
  --fs-0: 1.0625rem;
  --fs-1: 1.3125rem;
  --fs-2: 1.625rem;
  --fs-3: 2.0625rem;
  --fs-4: clamp(2.5625rem, 2rem + 2.4vw, 3.25rem);

  --measure: 65ch;
  --gutter: clamp(16px, 4vw, 40px);
  --radius: 6px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0e1319;
    --panel: #151c25;
    --panel-bar: #1b2430;
    --ink: #e4e9ef;
    --ink-2: #bdc6d1;
    --muted: #919daa;
    --rule: #334155;
    --rule-strong: #5c6c80;
    --accent: #8cb2fb;
    --accent-hover: #b0cafd;
    --accent-ink: #0b1320;
    --ident: #6ad0e0;
    --ok: #5fcd88;
    --warn: #e2b54a;
    --bad: #f5857b;
    --focus: #8cb2fb;
  }
}

/* ---------------------------------------------------------------------------------------------
   Base
   --------------------------------------------------------------------------------------------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: var(--fs-0);
  line-height: 1.6;
  overflow-wrap: break-word;
}

h1,
h2,
h3 {
  line-height: 1.2;
  text-wrap: balance;
  margin: 0;
}

h2 {
  font-size: var(--fs-2);
  font-weight: 700;
  letter-spacing: -0.01em;
}

h3 {
  font-size: var(--fs-1);
  font-weight: 650;
  letter-spacing: -0.005em;
}

p {
  margin: 0;
  text-wrap: pretty;
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--accent-hover);
  text-decoration-thickness: 2px;
}

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

code,
pre,
kbd,
samp {
  font-family: var(--mono);
}

/* Inline code in prose: the monospace carries it, with no chip behind it. */
p code,
li code,
td code,
th code,
dd code,
figcaption code {
  font-size: 0.92em;
  color: var(--ink);
}

ul {
  margin: 0;
  padding-left: 1.2em;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

.skip {
  position: absolute;
  left: var(--gutter);
  top: -3rem;
  padding: 0.5rem 0.8rem;
  background: var(--accent);
  color: var(--accent-ink);
  border-radius: var(--radius);
  z-index: 10;
}

.skip:focus {
  top: 0.75rem;
}

.wrap {
  max-width: 76rem;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* ---------------------------------------------------------------------------------------------
   Header
   --------------------------------------------------------------------------------------------- */
.site-head {
  border-bottom: 1px solid var(--rule);
}

.site-head .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 2rem;
  padding-block: 0.9rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--ink);
  font-weight: 700;
  font-size: var(--fs-1);
  letter-spacing: -0.01em;
  text-decoration: none;
}

.brand:hover {
  color: var(--ink);
}

.brand svg {
  width: 1.5rem;
  height: 1.5rem;
  flex: none;
  color: var(--accent);
}

.site-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1.25rem;
  list-style: none;
  padding: 0;
  font-size: var(--fs-sm);
}

.site-nav a {
  display: inline-block;
  padding-block: 0.25rem;
  color: var(--ink-2);
  text-decoration: none;
}

.site-nav a:hover {
  color: var(--accent);
  text-decoration: underline;
}

/* ---------------------------------------------------------------------------------------------
   Hero: sized to what it holds.
   --------------------------------------------------------------------------------------------- */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  align-items: center;
  gap: 2rem 4rem;
  padding-block: 3.5rem 3rem;
}

.hero h1 {
  font-size: var(--fs-4);
  font-weight: 800;
  letter-spacing: -0.03em;
}

.question {
  font-size: var(--fs-3);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-top: 0.75rem;
  max-width: 20ch;
  text-wrap: balance;
}

.hero-text > p:not(.question) {
  max-width: 52ch;
  margin-top: 1.25rem;
  color: var(--ink-2);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.75rem;
}

.btn {
  display: inline-block;
  padding: 0.65rem 1.1rem;
  border-radius: var(--radius);
  font-weight: 650;
  font-size: var(--fs-0);
  text-decoration: none;
  line-height: 1.3;
}

.btn-primary {
  background: var(--accent);
  color: var(--accent-ink);
  border: 1px solid var(--accent);
}

.btn-primary:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
  color: var(--accent-ink);
}

.btn-secondary {
  color: var(--ink);
  border: 1px solid var(--rule-strong);
}

.btn-secondary:hover {
  color: var(--ink);
  border-color: var(--ink);
}

.hero-figure {
  margin: 0;
}

.hero-figure figcaption {
  font-size: var(--fs-sm);
  color: var(--muted);
  margin-top: 0.5rem;
  max-width: 44ch;
}

/* The trigon. Lines are currentColor; the page's tokens decide which colour that is. */
.tri {
  display: block;
  width: 100%;
  height: auto;
  color: var(--ink);
  font-family: var(--sans);
}

.tri .claim {
  color: var(--muted);
}

.tri .vertex {
  fill: var(--bg);
  stroke: currentColor;
  stroke-width: 2.5;
}

.tri .name {
  fill: var(--ink);
  font-size: 24px;
  font-weight: 700;
}

.tri .sub {
  fill: var(--muted);
  font-size: 18px;
}

.tri .edge-label {
  fill: var(--ink-2);
  font-size: 19px;
}

.tri .claim-label {
  fill: var(--muted);
  font-style: italic;
}

.tri .meet-label {
  fill: var(--ink);
  font-size: 18px;
  font-weight: 600;
}

.tri .eq-bg {
  fill: var(--bg);
}

.tri .eq {
  fill: var(--ink);
  font-family: var(--mono);
  font-size: 30px;
  font-weight: 700;
}

/* ---------------------------------------------------------------------------------------------
   Sections: the heading holds a narrow left column, and the content the rest.
   --------------------------------------------------------------------------------------------- */
.sec {
  display: grid;
  grid-template-columns: minmax(0, 14rem) minmax(0, 1fr);
  gap: 1.25rem 3.5rem;
  padding-block: 3.75rem;
  border-top: 1px solid var(--rule);
}

.sec-head {
  align-self: start;
  position: sticky;
  top: 1.5rem;
}

.sec-head p {
  margin-top: 0.6rem;
  font-size: var(--fs-sm);
  color: var(--muted);
}

.sec-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2.25rem;
  min-width: 0;
}

.prose {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1rem;
  max-width: var(--measure);
}

.prose h3:not(:first-child) {
  margin-top: 1rem;
}

.lede {
  font-size: var(--fs-1);
  line-height: 1.45;
  color: var(--ink);
}

.muted {
  color: var(--muted);
}

/* A plain statement set apart by a rule, for the things a reader must not miss. */
.aside {
  border-left: 3px solid var(--ink);
  padding: 0.1rem 0 0.1rem 1.1rem;
  max-width: var(--measure);
  display: grid;
  gap: 0.75rem;
}

.aside h3 {
  font-size: var(--fs-0);
}

/* ---------------------------------------------------------------------------------------------
   The five ideas
   --------------------------------------------------------------------------------------------- */
.ideas {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2rem;
}

.idea {
  min-width: 0;
  border-top: 2px solid var(--ink);
  padding-top: 0.9rem;
  display: grid;
  gap: 0.6rem;
  align-content: start;
}

.idea > p {
  max-width: var(--measure);
}

/* ---------------------------------------------------------------------------------------------
   Outcomes, in the CLI's glyphs and colours
   --------------------------------------------------------------------------------------------- */
.ok {
  color: var(--ok);
}

.warn {
  color: var(--warn);
}

.bad {
  color: var(--bad);
}

.outcomes {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--fs-0);
}

.outcomes th,
.outcomes td {
  text-align: left;
  vertical-align: top;
  padding: 0.7rem 1rem 0.7rem 0;
  border-bottom: 1px solid var(--rule);
}

.outcomes thead th {
  font-size: var(--fs-xs);
  font-family: var(--mono);
  font-weight: 400;
  color: var(--muted);
  padding-top: 0;
}

.outcomes tbody th {
  padding-top: 0.85rem;
}

.outcomes .oc {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  font-family: var(--mono);
  font-weight: 700;
  font-size: var(--fs-sm);
}

.outcomes .glyph {
  flex: none;
  width: 1.2em;
  font-size: var(--fs-1);
  line-height: 1;
  text-align: center;
}

.outcomes tr.void th,
.outcomes tr.void td {
  border-top: 2px solid var(--rule-strong);
}

/* ---------------------------------------------------------------------------------------------
   The two halves
   --------------------------------------------------------------------------------------------- */
.halves {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border: 1px solid var(--rule);
  border-radius: var(--radius);
}

.half {
  padding: 1.25rem 1.4rem 1.4rem;
  display: grid;
  gap: 0.75rem;
  align-content: start;
}

.half + .half {
  border-left: 1px solid var(--rule);
}

.half-judgement {
  box-shadow: inset 3px 0 0 var(--ink);
}

.half-label {
  font-family: var(--mono);
  font-size: var(--fs-xs);
  color: var(--muted);
}

.half h4 {
  margin: 0;
  font-size: var(--fs-1);
  line-height: 1.2;
  text-wrap: balance;
}

.half ul:not(.crates) {
  display: grid;
  gap: 0.3rem;
}

.crates {
  list-style: none;
  padding: 0;
  font-family: var(--mono);
  font-size: var(--fs-xs);
  color: var(--ident);
  line-height: 1.7;
}

/* Each crate name stays whole; the line breaks only between names, after the separator. */
.crates li {
  display: inline;
  white-space: nowrap;
}

.crates li:not(:last-child)::after {
  content: " ·";
  content: " ·" / "";
}

/* ---------------------------------------------------------------------------------------------
   Terminal panels: real output, scrolled inside their own box.
   --------------------------------------------------------------------------------------------- */
.term {
  margin: 0;
  min-width: 0;
}

.term-box {
  background: var(--panel);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  min-width: 0;
}

.term-bar {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.25rem 1rem;
  padding: 0.45rem 1rem;
  background: var(--panel-bar);
  border-bottom: 1px solid var(--rule);
  border-radius: var(--radius) var(--radius) 0 0;
  font-family: var(--mono);
  font-size: var(--fs-xs);
  color: var(--muted);
}

.term pre {
  margin: 0;
  scrollbar-color: var(--rule-strong) var(--panel);
  padding: 0.9rem 1rem 1rem;
  overflow-x: auto;
  font-size: var(--fs-xs);
  line-height: 1.55;
  color: var(--ink);
  tab-size: 4;
}

.term pre:focus-visible {
  outline-offset: -3px;
}

.term figcaption {
  margin-top: 0.6rem;
  font-size: var(--fs-sm);
  color: var(--muted);
  max-width: var(--measure);
}

/* The CLI's palette (style.rs), mapped to the page tokens. */
.t-b {
  font-weight: 700;
}

.t-hd {
  font-weight: 700;
  color: var(--ink);
}

.t-lbl {
  font-weight: 700;
  color: var(--accent);
}

.t-id {
  color: var(--ident);
}

.t-mut,
.t-prompt {
  color: var(--muted);
}

.t-ok {
  color: var(--ok);
}

.t-warn {
  color: var(--warn);
}

.t-bad {
  color: var(--bad);
}

.t-cmd {
  font-weight: 700;
  color: var(--ink);
}

.t-note {
  color: var(--muted);
  font-style: italic;
}

/* A panel beside its notes on wide screens. */
.annotated {
  display: grid;
  grid-template-columns: minmax(0, 37rem) minmax(0, 1fr);
  gap: 1.5rem 2.25rem;
  align-items: start;
}

.notes {
  margin: 0;
  display: grid;
  gap: 0.9rem;
  font-size: var(--fs-sm);
}

.notes dt {
  font-family: var(--mono);
  font-weight: 700;
}

.notes dd {
  margin: 0.15rem 0 0;
  color: var(--ink-2);
}

/* Exit codes: the number in the monospace column, its meaning beside it. */
.codes {
  margin: 0;
  display: grid;
  gap: 0.35rem;
}

.codes > div {
  display: grid;
  grid-template-columns: 1.5rem minmax(0, 1fr);
  gap: 0.75rem;
}

.codes dt {
  font-family: var(--mono);
  font-weight: 700;
}

.codes dd {
  margin: 0;
}

/* ---------------------------------------------------------------------------------------------
   Plain data tables
   --------------------------------------------------------------------------------------------- */
.table-scroll {
  overflow-x: auto;
  min-width: 0;
  scrollbar-color: var(--rule-strong) var(--bg);
}

.data {
  border-collapse: collapse;
  font-size: var(--fs-sm);
  width: 100%;
}

.data-compact {
  width: auto;
  min-width: min(100%, 30rem);
}

.data caption {
  text-align: left;
  font-weight: 650;
  font-size: var(--fs-0);
  padding-bottom: 0.5rem;
}

.data th,
.data td {
  text-align: left;
  vertical-align: top;
  padding: 0.5rem 1rem 0.5rem 0;
  border-bottom: 1px solid var(--rule);
}

.data thead th {
  font-family: var(--mono);
  font-size: var(--fs-xs);
  font-weight: 400;
  color: var(--muted);
  white-space: nowrap;
}

.data tbody th {
  font-weight: 600;
}

.data .num {
  text-align: right;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.data .strong {
  font-weight: 700;
}

.pair {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 20rem), 1fr));
  gap: 1.5rem 2.5rem;
}

.state {
  font-family: var(--mono);
  font-size: var(--fs-xs);
  white-space: nowrap;
}

/* ---------------------------------------------------------------------------------------------
   Not built yet
   --------------------------------------------------------------------------------------------- */
.planned {
  border: 1px solid var(--rule-strong);
  border-radius: var(--radius);
  padding: 1.25rem 1.4rem 1.4rem;
  display: grid;
  gap: 0.9rem;
  max-width: var(--measure);
}

.planned ul {
  display: grid;
  gap: 0.7rem;
}

/* ---------------------------------------------------------------------------------------------
   Get started
   --------------------------------------------------------------------------------------------- */
.steps {
  display: grid;
  gap: 2rem;
}

.step {
  display: grid;
  gap: 0.6rem;
}

.step > p {
  max-width: var(--measure);
}

/* ---------------------------------------------------------------------------------------------
   Footer
   --------------------------------------------------------------------------------------------- */
.site-foot {
  border-top: 1px solid var(--rule);
  padding-block: 2.5rem 3rem;
  font-size: var(--fs-sm);
  color: var(--ink-2);
}

.foot-grid {
  display: grid;
  grid-template-columns: minmax(0, 14rem) repeat(auto-fit, minmax(min(100%, 13rem), 1fr));
  gap: 1.75rem 3.5rem;
}

.site-foot h2 {
  font-size: var(--fs-sm);
  font-family: var(--mono);
  font-weight: 400;
  color: var(--muted);
  margin-bottom: 0.6rem;
}

.site-foot ul {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 0.1rem;
}

.site-foot li a {
  display: inline-block;
  padding-block: 0.25rem;
}

.site-foot .brand {
  font-size: var(--fs-0);
}

.site-foot .brand svg {
  width: 1.25rem;
  height: 1.25rem;
}

.foot-line {
  margin-top: 0.75rem;
  color: var(--muted);
}

/* ---------------------------------------------------------------------------------------------
   Narrow screens
   --------------------------------------------------------------------------------------------- */
@media (max-width: 960px) {
  .annotated {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 860px) {
  .hero {
    grid-template-columns: minmax(0, 1fr);
    padding-block: 2.5rem 2rem;
  }

  .hero-figure {
    max-width: 30rem;
  }

  .sec {
    grid-template-columns: minmax(0, 1fr);
    padding-block: 2.75rem;
  }

  .sec-head {
    position: static;
  }

  .halves {
    grid-template-columns: minmax(0, 1fr);
  }

  .half + .half {
    border-left: 0;
    border-top: 1px solid var(--rule);
  }

  .foot-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 520px) {
  /* The diagram scales to about 0.6 here; larger labels keep it readable. */
  .tri .name {
    font-size: 28px;
  }

  .tri .sub,
  .tri .meet-label,
  .tri .edge-label {
    font-size: 23px;
  }

  .data th,
  .data td {
    padding-right: 0.6rem;
  }

  .outcomes th,
  .outcomes td {
    padding-right: 0.6rem;
  }
}

/* An identifier never breaks at its hyphens. Below 360px a long one may wrap rather than overflow. */
@media (min-width: 360px) {
  :is(p, li, dd, td, th, figcaption) code {
    white-space: nowrap;
  }
}

/* A long command that may break only where the markup allows it, between .nw runs. */
code.breakable {
  white-space: normal;
}

.nw {
  white-space: nowrap;
}

@media (forced-colors: active) {
  .tri text {
    fill: CanvasText;
  }

  .tri .vertex,
  .tri .eq-bg {
    fill: Canvas;
  }
}

@media (prefers-reduced-motion: no-preference) {
  html {
    scroll-behavior: smooth;
  }

  a,
  .btn {
    transition: color 120ms ease, background-color 120ms ease, border-color 120ms ease;
  }
}