/* ==========================================================================
   base.css — reset, typography, the 12-column grid, header and primitives.
   ========================================================================== */

*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 24px);
}
body {
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: var(--fs-base);
  font-weight: var(--fw-book);
  line-height: var(--lh-body);
  letter-spacing: var(--tracking-body);
  font-kerning: normal;
  font-synthesis: none; /* never fake a bold or italic Avenir face */
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}
img, svg, canvas { display: block; max-width: 100%; }
ul, ol { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
button, input { font: inherit; color: inherit; }
button { cursor: pointer; background: none; border: 0; padding: 0; }
h1, h2, h3 { font-weight: var(--fw-heavy); letter-spacing: var(--tracking-heading); text-wrap: balance; }
p, li, dd { text-wrap: pretty; }
::selection { background: var(--accent); color: var(--accent-ink); }

/* ---- Utilities --------------------------------------------------------- */
.sr-only {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0);
  white-space: nowrap; border: 0;
}
.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
/* Technical micro-labels: Avenir Medium, lightly tracked, tabular figures. */
.mono {
  font-family: var(--font-label);
  font-size: var(--fs-xs);
  font-weight: var(--fw-medium);
  letter-spacing: var(--tracking-label);
  font-variant-numeric: tabular-nums;
}
.muted { color: var(--muted); }
.label { color: var(--muted); }
html:not(.js) [data-js-only] { display: none !important; }

kbd {
  display: inline-grid;
  place-items: center;
  min-width: 1.6em;
  padding: 0.05em 0.4em;
  border: var(--hairline) solid var(--line-strong);
  border-bottom-width: 2px;
  border-radius: var(--radius-xs);
  font-family: var(--font-mono);
  font-size: 0.85em;
  font-weight: var(--fw-book);
  letter-spacing: 0;
  line-height: 1.5;
  color: var(--ink-2);
  background: var(--bg-elev);
}

/* ---- Focus: visible, consistent, never removed ------------------------- */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

.skip-link {
  position: fixed;
  top: 10px; left: 10px;
  z-index: 100;
  padding: 0.6rem 1rem;
  background: var(--ink);
  color: var(--bg);
  border-radius: var(--radius-sm);
  font-size: var(--fs-sm);
  transform: translateY(-160%);
  transition: transform var(--dur-2) var(--ease-out);
}
.skip-link:focus-visible { transform: none; }

/* ---- Icons -------------------------------------------------------------- */
.icon {
  width: 1.25em;
  height: 1.25em;
  flex: none;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
  overflow: visible;
}

/* ---- Layout ------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: calc(var(--container) + 2 * var(--gutter));
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.grid {
  display: grid;
  grid-template-columns: repeat(var(--cols), minmax(0, 1fr));
  column-gap: var(--col-gap);
}
.grid > * { grid-column: 1 / -1; }

.section {
  position: relative;
  padding-block: var(--space-section) 0;
}
.section-head {
  margin-bottom: var(--space-block);
  padding-top: var(--s-5);
  border-top: var(--hairline) solid var(--line);
  position: relative;
}
/* Registration tick on the section rule, like a drawing sheet. */
.section-head::before {
  content: "";
  position: absolute;
  top: -4px; left: 0;
  width: 7px; height: 7px;
  border: var(--hairline) solid var(--line-strong);
  background: var(--bg);
  transform: rotate(45deg);
}
.section-num {
  color: var(--muted);
  margin-bottom: var(--s-4);
}
.section-num span { color: var(--accent); }
.section-title {
  font-family: var(--font-display);
  font-size: var(--fs-2xl);
  font-weight: var(--fw-heavy);
  line-height: var(--lh-tight);
  letter-spacing: var(--tracking-display);
  max-width: 20ch;
}
/* Accent words switch from Heavy to Light instead of a faux italic. */
.section-title em, .hero-name-italic { font-style: normal; font-weight: var(--fw-light); color: var(--ink-2); }
.section-note {
  margin-top: var(--s-4);
  max-width: 56ch;
  color: var(--ink-2);
  font-size: var(--fs-sm);
}
@media (min-width: 900px) {
  .section-head {
    display: grid;
    grid-template-columns: subgrid;
    grid-column: 1 / -1;
    align-items: end;
  }
  .section-num { grid-column: 1 / 4; align-self: start; }
  .section-title { grid-column: 4 / 11; }
  .section-note { grid-column: 4 / 11; }
}

.prose p + p { margin-top: var(--s-4); }
.prose { color: var(--ink-2); }
.lead {
  font-size: var(--fs-lg);
  line-height: 1.5;
  color: var(--ink);
}

/* ---- Header ------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  -webkit-backdrop-filter: saturate(1.4) blur(14px);
  backdrop-filter: saturate(1.4) blur(14px);
  border-bottom: var(--hairline) solid var(--line);
}
.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  gap: var(--s-5);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  margin-right: auto;
}
.brand-mark {
  width: 28px; height: 28px;
  padding: 4px;
  border: var(--hairline) solid var(--line-strong);
  border-radius: var(--radius-xs);
  color: var(--accent);
  stroke-width: 1.75;
}
.brand-text { color: var(--ink-2); }

.site-nav ul { display: flex; gap: clamp(0.75rem, 1.6vw, 1.6rem); }
.site-nav a {
  display: inline-flex;
  align-items: baseline;
  gap: 0.35rem;
  padding-block: 0.4rem;
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  color: var(--ink-2);
  transition: color var(--dur-1) var(--ease-out);
}
.site-nav a .mono { font-size: var(--fs-2xs); color: var(--muted); }
.site-nav a:hover, .site-nav a[aria-current] { color: var(--ink); }
.site-nav a[aria-current] .mono { color: var(--accent); }

.header-actions { display: flex; align-items: center; gap: 0.5rem; }
.palette-trigger, .theme-toggle, .nav-menu summary {
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  border: var(--hairline) solid var(--line-strong);
  border-radius: var(--radius-sm);
  color: var(--ink-2);
  background: var(--bg-elev);
  transition: border-color var(--dur-1) var(--ease-out), color var(--dur-1) var(--ease-out);
}
.palette-trigger { padding-inline: 0.55rem 0.4rem; }
.palette-trigger kbd { border: 0; background: var(--bg-sunk); font-size: var(--fs-2xs); }
.theme-toggle { width: 36px; }
.palette-trigger:hover, .theme-toggle:hover, .nav-menu summary:hover { border-color: var(--ink-2); color: var(--ink); }

/* Mobile menu: a <details> element, so it works with or without JS. */
.nav-menu { position: relative; display: none; }
.nav-menu summary { width: 36px; list-style: none; }
.nav-menu summary::-webkit-details-marker { display: none; }
.nav-menu-bars { display: grid; gap: 5px; width: 16px; }
.nav-menu-bars i {
  display: block; height: 1.5px; border-radius: 2px;
  background: currentColor;
  transition: transform var(--dur-2) var(--ease-out);
}
.nav-menu[open] .nav-menu-bars i:first-child { transform: translateY(3.25px) rotate(45deg); }
.nav-menu[open] .nav-menu-bars i:last-child { transform: translateY(-3.25px) rotate(-45deg); }
.nav-menu-list {
  position: absolute;
  right: 0; top: calc(100% + 10px);
  min-width: 220px;
  padding: 0.4rem;
  background: var(--bg-elev);
  border: var(--hairline) solid var(--line-strong);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.nav-menu-list a {
  display: flex; gap: 0.75rem; align-items: baseline;
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius-xs);
}
.nav-menu-list a:hover { background: var(--bg-sunk); }
.nav-menu-list .mono { color: var(--muted); }

@media (max-width: 1100px) {
  .site-nav { display: none; }
  .nav-menu { display: block; }
}
@media (max-width: 420px) {
  .brand-text { display: none; }
  .palette-trigger kbd { display: none; }
  .palette-trigger { width: 36px; padding: 0; }
}

/* ---- Buttons ------------------------------------------------------------ */
.btn {
  --btn-h: 48px;
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  height: var(--btn-h);
  padding-inline: 1.25rem;
  border-radius: var(--radius-pill);
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  letter-spacing: 0.01em;
  border: var(--hairline) solid transparent;
  transition:
    background-color var(--dur-2) var(--ease-out),
    border-color var(--dur-2) var(--ease-out),
    color var(--dur-2) var(--ease-out);
  will-change: transform;
}
.btn-primary { background: var(--ink); color: var(--bg); }
.btn-primary:hover { background: var(--accent); color: var(--accent-ink); }
.btn-ghost { border-color: var(--line-strong); color: var(--ink); }
.btn-ghost:hover { border-color: var(--ink); }
.btn .icon { transition: transform var(--dur-2) var(--ease-spring); }
.btn-ghost:hover .icon { transform: translateX(3px); }
.btn-primary:hover .icon { transform: translateY(2px); }
/* Compact size for secondary actions (e.g. copy email): same shape, smaller. */
.btn-sm { --btn-h: 36px; padding-inline: 0.8rem 0.95rem; gap: 0.45rem; font-size: var(--fs-xs); }

/* ---- Cards -------------------------------------------------------------- */
.card {
  position: relative;
  background: var(--bg-elev);
  border: var(--hairline) solid var(--line);
  border-radius: var(--radius-lg);
  isolation: isolate;
}

/* ---- Tags: one pill shape for chips, status pills and badges ---------- */
.chips { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.chips > *, .pill, .badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.2rem 0.65rem;
  border: var(--hairline) solid var(--line-strong);
  border-radius: var(--radius-pill);
  font-family: var(--font-label);
  font-size: var(--fs-2xs);
  font-weight: var(--fw-medium);
  letter-spacing: var(--tracking-label);
  line-height: 1.5;
  color: var(--ink-2);
  background: var(--bg);
  white-space: nowrap;
}
.pill { border-color: color-mix(in srgb, var(--ok) 50%, transparent); color: var(--ok); }
.pill-muted { border-color: var(--line-strong); color: var(--muted); }
.badge { border-color: color-mix(in srgb, var(--accent) 25%, transparent); background: var(--accent-soft); white-space: normal; }
.badge .icon { color: var(--accent); }