/* falcon_mdf site — "research lab" minimalism modelled on rightnowai.co/research:
 * warm near-black paper, JetBrains Mono everywhere, hairline rules, 2px radius,
 * stacked-paper card shadows, uppercase mono buttons, numbered sections,
 * figure captions. Structure notes live in tokens.css; this file is layout.
 */
@import "tokens.css";

* { box-sizing: border-box; }

html { overflow-x: clip; }
body { overflow-x: clip; }

body {
  margin: 0;
  background: var(--color-paper);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.75;
  /* the theme toggle flips these; everything else snaps instantly */
  transition: background-color var(--dur-short) var(--ease-out), color var(--dur-short) var(--ease-out);
}

::selection { background: var(--color-accent-soft); color: var(--color-ink); }

/* --- shared primitives --------------------------------------------------- */

.wrap {
  max-width: var(--content);
  margin-inline: auto;
  padding-inline: clamp(1rem, 4vw, 2.5rem);
}

a { color: var(--color-ink); text-decoration: none; }
a:hover { color: var(--color-accent-bright); text-decoration: underline; text-underline-offset: 3px; }

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

h1, h2, h3 {
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.03em;
  overflow-wrap: anywhere;
  min-width: 0;
}

code, pre { font-variant-numeric: tabular-nums; }

.mono { font-family: var(--font-display); }

/* buttons — uppercase mono, near-square, faint inner bevel like the reference */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  font-family: var(--font-display);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  white-space: nowrap;
  padding: 0 var(--space-lg);
  min-height: 44px;
  border: 1px solid var(--color-rule);
  border-radius: var(--radius);
  background: var(--color-tint);
  color: var(--color-ink);
  box-shadow: inset 1px 1px 0 var(--bevel-hi), inset -1px -1px 0 var(--bevel-lo);
  cursor: pointer;
  transition: background var(--dur-short) var(--ease-out), border-color var(--dur-short) var(--ease-out);
}
.btn:hover {
  text-decoration: none;
  color: var(--color-ink);
  border-color: var(--color-rule-strong);
  background: var(--color-tint-strong);
}
.btn:active { transform: translateY(1px); }

.btn--primary {
  border-color: rgba(0, 0, 0, 0.5);
  background: var(--color-accent);
  color: var(--color-accent-ink);
  box-shadow: inset 1px 1px 0 rgba(255, 255, 255, 0.35), inset -1px -1px 0 rgba(0, 0, 0, 0.25);
}
.btn--primary:hover {
  background: var(--color-accent-bright);
  border-color: rgba(0, 0, 0, 0.6);
  color: var(--color-accent-ink);
}

@media (pointer: coarse) {
  .btn { min-height: 48px; }
}

/* panels — hairline box; the stacked variant drops a hard offset shadow,
   the reference's "printed card" effect */
.panel {
  position: relative;
  isolation: isolate;
  background: var(--color-paper-2);
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
}
.panel--stack::before {
  content: "";
  position: absolute;
  z-index: -1;
  top: 6px;
  left: 6px;
  right: -6px;
  bottom: -6px;
  background: var(--shadow-card-bg);
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
}

/* chips — small mono tags, the reference's vocabulary for capabilities */
.chips {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2xs);
  margin: 0;
  padding: 0;
}
.chips li {
  font-size: var(--text-xs);
  color: var(--color-muted);
  padding: 0.15rem 0.55rem;
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
  background: var(--color-tint);
  white-space: nowrap;
}

/* figures — real captures in hairline frames; captions numbered like a paper */
.figure { margin: 0; min-width: 0; }
.figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
}
figcaption {
  font-size: var(--text-xs);
  color: var(--color-faint);
  padding-top: var(--space-sm);
  letter-spacing: 0.01em;
}
figcaption b { color: var(--color-muted); font-weight: 400; }

/* --- nav ------------------------------------------------------------------- */

.nav {
  border-bottom: 1px solid var(--color-rule-2);
  background: var(--color-paper);
}
.nav__line {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding-block: var(--space-md);
}
.nav__brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-weight: 700;
  font-size: var(--text-base);
  letter-spacing: -0.02em;
  color: var(--color-ink);
}
.nav__brand:hover { color: var(--color-ink); text-decoration: none; }
.nav__brand img { flex: none; }
.nav__links {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-xs) var(--space-lg);
  margin-left: auto;
  font-size: var(--text-sm);
}
.nav__links a { color: var(--color-muted); white-space: nowrap; }
.nav__links a:hover { color: var(--color-accent-bright); text-decoration: none; }
.nav__links .btn { margin-left: var(--space-xs); }

/* theme toggle — a quiet square beside the nav links; the active theme's
   icon is hidden so the button always shows where a click will take you */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  min-height: 44px;
  margin-left: var(--space-xs);
  border: 1px solid var(--color-rule);
  border-radius: var(--radius);
  background: var(--color-tint);
  color: var(--color-muted);
  box-shadow: inset 1px 1px 0 var(--bevel-hi), inset -1px -1px 0 var(--bevel-lo);
  cursor: pointer;
  transition: background var(--dur-short) var(--ease-out), border-color var(--dur-short) var(--ease-out), color var(--dur-short) var(--ease-out);
}
.theme-toggle:hover {
  color: var(--color-ink);
  border-color: var(--color-rule-strong);
  background: var(--color-tint-strong);
}
.theme-toggle:active { transform: translateY(1px); }
.theme-toggle .icon-sun { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
:root[data-theme="dark"] .theme-toggle .icon-moon { display: none; }
@media (pointer: coarse) {
  .theme-toggle { width: 48px; min-height: 48px; }
}

/* --- hero: centred title, abstract panel, two CTAs --------------------------- */

.hero { padding-block: var(--space-3xl) var(--space-2xl); }
.hero__in {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}
/* The wordmark has a light and a dark variant; the site's own toggle picks
   one, so the swap follows data-theme rather than prefers-color-scheme. */
.hero__logo {
  width: min(560px, 100%);
  height: auto;
  margin: 0 0 var(--space-xl);
}
.hero__logo--dark { display: none; }
:root[data-theme="dark"] .hero__logo--light { display: none; }
:root[data-theme="dark"] .hero__logo--dark { display: block; }
.hero__kicker {
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
  color: var(--color-muted);
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
  background: var(--color-tint);
  padding: 0.3rem 0.8rem;
  margin: 0 0 var(--space-xl);
}
.hero h1 {
  font-size: var(--text-display);
  margin: 0 0 var(--space-md);
  max-width: 24ch;
}
.hero__sub {
  color: var(--color-muted);
  max-width: 58ch;
  margin: 0 0 var(--space-xl);
  font-size: var(--text-md);
  line-height: 1.65;
}
.hero__sub b { color: var(--color-ink); font-weight: 600; }

/* the abstract — the page's thesis, set like a paper's */
.abstract {
  width: 100%;
  max-width: 46rem;
  text-align: left;
  background: var(--color-paper-2);
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
  padding: var(--space-lg);
  margin: 0 0 var(--space-xl);
}
.abstract__label {
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-faint);
  margin: 0 0 var(--space-sm);
}
.abstract > p {
  margin: 0;
  color: var(--color-muted);
  font-size: var(--text-sm);
  line-height: 1.8;
}
.abstract b { color: var(--color-ink); font-weight: 600; }

.hero__cta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-md);
}
.hero__note {
  font-size: var(--text-xs);
  color: var(--color-faint);
  margin: var(--space-lg) 0 0;
}

/* figure 1 — the hero capture, full measure */
.hero-fig { padding-bottom: var(--space-2xl); }

/* --- sections: numbered, hairline-separated ---------------------------------- */

.sec { padding-block: var(--space-2xl); border-top: 1px solid var(--color-rule-2); }
.sec__head { margin: 0 0 var(--space-xl); max-width: 62ch; }
.sec__head h2 {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  font-size: var(--text-display-s);
  margin: 0 0 var(--space-sm);
}
.sec__n {
  flex: none;
  display: inline-grid;
  place-items: center;
  width: 2.3rem;
  height: 2.3rem;
  font-size: var(--text-base);
  font-weight: 600;
  letter-spacing: 0;
  color: var(--color-accent-text);
  background: var(--color-paper-2);
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
}
.sec__head > p { color: var(--color-muted); margin: 0; }
.sec__head b { color: var(--color-ink); font-weight: 600; }

/* --- 1 · the playground: stacked tour cards ---------------------------------- */

.shot { margin: 0 0 var(--space-sm); }
/* clear the card's 6px offset shadow before the caption starts */
.figcap {
  font-size: var(--text-xs);
  color: var(--color-faint);
  margin: 1rem 0 var(--space-2xl);
}
.figcap b { color: var(--color-muted); font-weight: 400; }
.shot + .figcap:last-child { margin-bottom: 0; }
.shot > .figure img { border: 0; border-bottom: 1px solid var(--color-rule-2); border-radius: var(--radius) var(--radius) 0 0; }
.shot__body { padding: var(--space-lg); }
.shot__body h3 { font-size: var(--text-lg); margin: 0 0 var(--space-sm); }
.shot__body > p { margin: 0 0 var(--space-md); color: var(--color-muted); max-width: 72ch; }
.shot__row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
}
.shot__link {
  font-size: var(--text-sm);
  color: var(--color-accent-text);
  white-space: nowrap;
}
.shot__link:hover { color: var(--color-accent-bright); }

/* --- 2 · measured numbers ------------------------------------------------------ */

.stats__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
  background: var(--color-paper-2);
}
.stat { padding: var(--space-lg); }
.stat + .stat { border-left: 1px solid var(--color-rule-2); }
.stat__n {
  font-size: var(--text-2xl);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin: 0;
  font-variant-numeric: tabular-nums;
}
.stat__n small { font-size: 0.55em; color: var(--color-accent-text); font-weight: 600; }
.stat__q {
  margin: var(--space-sm) 0 0;
  font-size: var(--text-xs);
  color: var(--color-muted);
  line-height: 1.6;
}
.stats__foot {
  margin: var(--space-lg) 0 0;
  font-size: var(--text-xs);
  color: var(--color-faint);
  max-width: 72ch;
}
.stats__foot a { color: var(--color-muted); text-decoration: underline; text-underline-offset: 3px; }
.stats__foot a:hover { color: var(--color-accent-bright); }

/* --- 3 · what is mdf: a short primer --------------------------------------------- */

.mdf-primer { max-width: 72ch; }
.mdf-primer > p { margin: 0 0 var(--space-md); color: var(--color-muted); }
.mdf-primer > p:last-child { margin-bottom: 0; }
.mdf-primer b { color: var(--color-ink); font-weight: 600; }
.mdf-primer__refs {
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-rule-2);
  font-size: var(--text-sm);
}
.mdf-primer a { text-decoration: underline; text-underline-offset: 3px; }

/* --- 4 · what it reads: the spec sheet ------------------------------------------ */

.spec__row {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
  gap: var(--space-sm) var(--space-xl);
  padding-block: var(--space-md);
  border-top: 1px solid var(--color-rule-2);
}
.spec__row:last-child { border-bottom: 1px solid var(--color-rule-2); }
.spec__k {
  font-size: var(--text-sm);
  color: var(--color-faint);
  margin: 0;
}
.spec__v { margin: 0; color: var(--color-muted); }
.spec__v b { color: var(--color-ink); font-weight: 600; }

/* --- 5 · add it to your project --------------------------------------------------- */

.code__grid {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: var(--space-2xl);
  align-items: start;
}
.code__head { max-width: 46ch; }
.code__head h2 {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  font-size: var(--text-display-s);
  margin: 0 0 var(--space-md);
}
.code__head > p { color: var(--color-muted); margin: 0 0 var(--space-lg); }
.install {
  display: flex;
  align-items: stretch;
  gap: var(--space-sm);
  font-size: var(--text-sm);
}
.install pre {
  margin: 0;
  padding: 0 var(--space-md);
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  background: var(--color-paper-2);
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
  overflow-x: auto;
}
.install .prompt { color: var(--color-faint); user-select: none; }
.copy {
  border: 1px solid var(--color-rule);
  background: var(--color-tint);
  color: var(--color-muted);
  font-family: var(--font-display);
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 0 var(--space-md);
  min-height: 44px;
  min-width: 44px;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background var(--dur-short) var(--ease-out), border-color var(--dur-short) var(--ease-out);
}
.copy:hover { border-color: var(--color-rule-strong); color: var(--color-ink); background: var(--color-tint-strong); }
.copy:active { transform: translateY(1px); }
.btn:disabled, .copy:disabled { opacity: 0.45; cursor: not-allowed; }

.codeblock { padding: var(--space-lg); }
.codeblock__label {
  font-size: var(--text-xs);
  color: var(--color-faint);
  margin: 0 0 var(--space-md);
  letter-spacing: 0.05em;
}
.codeblock pre {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.7;
  overflow-x: auto;
  color: var(--color-ink);
}
.codeblock .kw { color: var(--color-accent-text); }
.codeblock .str { color: var(--color-syntax-str); }
.codeblock .fn { color: var(--color-syntax-fn); }
.codeblock .cm { color: var(--color-faint); }

/* --- 6 · what it refuses ------------------------------------------------------------ */

.limits ul { list-style: none; margin: 0; padding: 0; }
.limits li {
  padding-block: var(--space-md);
  border-top: 1px solid var(--color-rule-2);
  color: var(--color-muted);
}
.limits li:last-child { border-bottom: 1px solid var(--color-rule-2); }
.limits li b { color: var(--color-ink); font-weight: 600; }

/* --- 7 · the live embed --------------------------------------------------------------- */

.play__head {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  gap: var(--space-xl);
  align-items: end;
  margin-bottom: var(--space-xl);
}
.play__head h2 {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  font-size: var(--text-display-s);
  margin: 0 0 var(--space-sm);
}
.play__head p { color: var(--color-muted); margin: 0; max-width: 52ch; }
.play__launch { text-align: right; }
.play__stage {
  min-height: 320px;
  display: grid;
  place-items: center;
  padding: var(--space-xl);
}
/* once the viewer is live, the stage chrome steps aside — the iframe owns
   the full width and carries its own surface */
.play__stage.is-live {
  background: transparent;
  border: 0;
  min-height: 0;
  padding: 0;
  display: block;
}
.play__stage.is-live::before { display: none; }
.play__gate { text-align: center; max-width: 48ch; }
.play__gate p {
  font-size: var(--text-sm);
  color: var(--color-muted);
  margin: 0 0 var(--space-lg);
}
.play__frame { display: none; }
.play__frame.is-live { display: block; width: 100%; }
.play__frame iframe {
  display: block;
  width: 100%;
  min-width: 0;
  height: min(78vh, 860px);
  border: 1px solid var(--color-rule-2);
  border-radius: var(--radius);
  background: var(--color-paper);
}
.play__facts {
  margin: var(--space-lg) 0 0;
  font-size: var(--text-xs);
  color: var(--color-faint);
}

/* --- colophon --------------------------------------------------------------------------- */

.colophon {
  border-top: 1px solid var(--color-rule-2);
  padding-block: var(--space-2xl) var(--space-xl);
  background: var(--color-paper);
}
.colophon__grid {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  gap: var(--space-xl);
  font-size: var(--text-sm);
  line-height: 1.8;
  color: var(--color-muted);
}
.colophon__mark {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: var(--text-lg);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-ink);
  margin-bottom: var(--space-sm);
}
.colophon__mark img { flex: none; }
.colophon p { margin: 0 0 var(--space-md); }
.colophon__cols {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-lg);
}
.colophon ul { list-style: none; margin: 0; padding: 0; }
.colophon li { margin-bottom: var(--space-2xs); }
.colophon a { color: var(--color-muted); }
.colophon a:hover { color: var(--color-accent-bright); }
.colophon__fine {
  margin: var(--space-xl) 0 0;
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-rule-2);
  font-size: var(--text-xs);
  color: var(--color-faint);
  max-width: 88ch;
}

/* --- responsive -------------------------------------------------------------------------- */

@media (max-width: 60rem) {
  .stats__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stat:nth-child(3) { border-left: 0; }
  .stat:nth-child(n+3) { border-top: 1px solid var(--color-rule-2); }
  .code__grid { grid-template-columns: minmax(0, 1fr); gap: var(--space-xl); }
  .play__head { grid-template-columns: minmax(0, 1fr); gap: var(--space-md); }
  .play__launch { text-align: left; }
  .colophon__grid { grid-template-columns: minmax(0, 1fr); }
  .spec__row { grid-template-columns: minmax(0, 1fr); gap: var(--space-2xs); }
  .panel--stack::before { top: 4px; left: 4px; right: -4px; bottom: -4px; }
}

@media (max-width: 40rem) {
  .hero { padding-block: var(--space-2xl); }
  .hero h1 { font-size: var(--text-display-s); }
  .hero__sub { font-size: var(--text-base); }
  .stats__grid { grid-template-columns: minmax(0, 1fr); }
  .stat + .stat { border-left: 0; border-top: 1px solid var(--color-rule-2); }
  .stat:nth-child(3) { border-left: 0; }
  .stat:nth-child(n+3) { border-top: 1px solid var(--color-rule-2); }
  .nav__line { flex-wrap: wrap; row-gap: var(--space-xs); }
  .nav__links { margin-left: 0; }
  .sec__head h2, .code__head h2, .play__head h2 { font-size: var(--text-lg); }
  .sec__n { width: 1.9rem; height: 1.9rem; }
  .abstract { padding: var(--space-md); }
  .codeblock { padding: var(--space-md); }
  .codeblock pre { font-size: var(--text-xs); }
  .panel--stack::before { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition-duration: 0ms !important; }
}