@font-face {
  font-family: 'Fraunces';
  src: url('fonts/fraunces-latin.woff2') format('woff2');
  font-style: normal;
  font-weight: 350 400;
  font-display: swap;
}

@font-face {
  font-family: 'IBM Plex Mono';
  src: url('fonts/ibm-plex-mono-latin-400.woff2') format('woff2');
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}

@font-face {
  font-family: 'IBM Plex Mono';
  src: url('fonts/ibm-plex-mono-latin-500.woff2') format('woff2');
  font-style: normal;
  font-weight: 500;
  font-display: swap;
}

:root {
  color-scheme: light dark;
  --paper: #f2efe7;
  --surface: #faf8f2;
  --ink: #1a1c1f;
  --muted: #6b6a63;
  --rule: #88847b;
  --rule-strong: #747169;
  --green: #1f3d33;
  --green-hover: #2e5547;
  --success: #3d6b4f;
  --warning: #8c5a22;
  --error: #8a3b2e;
  --maxw: 1080px;
  --prose: 780px;
  --header-offset: 96px;
  --body-serif: Charter, 'Bitstream Charter', 'Iowan Old Style', 'Palatino Linotype', Palatino, Georgia, serif;
  --mono: 'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

[data-theme='dark'] {
  --paper: #16181a;
  --surface: #1d2023;
  --ink: #e8e4da;
  --muted: #96938a;
  --rule: #6f7479;
  --rule-strong: #7f858b;
  --green: #8fb3a4;
  --green-hover: #a8cabb;
  --success: #7fb391;
  --warning: #cf9d5a;
  --error: #d27663;
}

* { box-sizing: border-box; }

html { background: var(--paper); }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--body-serif);
  font-size: 17px;
  line-height: 1.55;
}

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

a:hover { color: var(--green-hover); }

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

.wrap {
  width: min(100%, var(--maxw));
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 32px);
}

.prose { max-width: var(--prose); }

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 100;
  padding: 10px 14px;
  background: var(--green);
  color: var(--paper);
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  transform: translateY(-160%);
}

.skip-link:focus { transform: translateY(0); }

/* Shared site header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: var(--paper);
  backdrop-filter: blur(6px);
}

@supports (background: color-mix(in srgb, white, transparent)) {
  .site-header { background: color-mix(in srgb, var(--paper) 94%, transparent); }
}

.progress-track {
  position: relative;
  height: 12px;
  overflow: hidden;
  border-bottom: 1px solid var(--rule-strong);
}

.progress-track::before {
  content: '';
  position: absolute;
  inset: 6px 0 0;
  background-image: repeating-linear-gradient(
    to right,
    var(--rule) 0,
    var(--rule) 1px,
    transparent 1px,
    transparent 16px
  );
}

.progress-index {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 2px;
  height: 12px;
  background: var(--green);
  transform: translate3d(0, 0, 0);
  will-change: transform;
}

.nav-shell {
  display: flex;
  min-height: 58px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 1px solid var(--rule);
}

.brand-lockup {
  --pl-mark-accent: var(--green);
  --pl-mark-rule: var(--muted);
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-decoration: none;
  text-transform: uppercase;
  white-space: nowrap;
}

.brand-lockup:hover { color: var(--green-hover); }
.brand-mark { flex: 0 0 auto; }

.desktop-nav {
  display: flex;
  align-items: center;
  gap: 20px;
}

.nav-link,
.nav-cta,
.theme-toggle,
.mobile-nav summary {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.nav-link,
.nav-cta {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  color: var(--muted);
  text-decoration: none;
}

.nav-link:hover { color: var(--green-hover); }

.nav-cta {
  border-bottom: 1px solid var(--green);
  color: var(--green);
}

.nav-cta:hover {
  border-color: var(--green-hover);
  color: var(--green-hover);
}

.theme-toggle {
  min-height: 36px;
  padding: 5px 10px;
  border: 1px solid var(--rule-strong);
  border-radius: 0;
  background: var(--paper);
  color: var(--ink);
  cursor: pointer;
}

.theme-toggle:hover {
  border-color: var(--green-hover);
  color: var(--green-hover);
}

.mobile-nav { display: none; }

/* Page structure and typography */
main > section {
  padding-block: 64px;
  border-bottom: 1px solid var(--rule);
}

main > section[id] { scroll-margin-top: var(--header-offset); }

.hero {
  padding-top: clamp(72px, 10vw, 112px);
  padding-bottom: clamp(72px, 9vw, 96px);
}

.section-label {
  display: flex;
  align-items: center;
  gap: 16px;
  margin: 0 0 24px;
  color: var(--green);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}

.section-label .section-num {
  color: var(--muted);
  font-weight: 400;
}

.section-label::after {
  content: '';
  flex: 1;
  max-width: 360px;
  height: 1px;
  background: var(--rule);
}

h1,
h2,
h3 {
  margin: 0 0 18px;
  color: var(--ink);
  font-family: 'Fraunces', Charter, Georgia, serif;
  font-weight: 350;
  letter-spacing: -0.01em;
  text-wrap: balance;
}

h1 {
  max-width: 17ch;
  font-size: clamp(40px, 6vw, 64px);
  font-variation-settings: 'opsz' 96;
  line-height: 1.05;
}

h2 {
  max-width: 24ch;
  font-size: clamp(28px, 4vw, 40px);
  font-variation-settings: 'opsz' 60;
  line-height: 1.15;
}

h3 {
  font-size: 21px;
  font-weight: 400;
  line-height: 1.3;
}

p { margin: 0 0 16px; }

.lead {
  max-width: 64ch;
  color: var(--muted);
  font-size: 20px;
  line-height: 1.5;
}

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

.content-note {
  max-width: 64ch;
  margin-top: 24px;
  color: var(--muted);
}

.meta {
  margin-bottom: 12px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 28px;
}

.btn {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  padding: 12px 22px;
  border: 1px solid var(--green);
  border-radius: 0;
  background: var(--green);
  color: var(--paper);
  cursor: pointer;
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-decoration: none;
  text-transform: uppercase;
}

.btn:hover {
  border-color: var(--green-hover);
  background: var(--green-hover);
  color: var(--paper);
}

.btn.secondary,
.btn.ghost {
  background: transparent;
  color: var(--green);
}

.btn.secondary:hover,
.btn.ghost:hover {
  border-color: var(--green-hover);
  color: var(--green-hover);
}

.btn.ghost {
  padding-inline: 0;
  border-color: transparent;
}

.btn.ghost::after { content: ' →'; }

/* Homepage patterns */
.checks-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 48px;
  margin-top: 28px;
}

ul.checks {
  padding: 0;
  margin: 0;
  list-style: none;
}

ul.checks li {
  position: relative;
  margin-bottom: 14px;
  padding-left: 26px;
  color: var(--muted);
}

ul.checks li::before {
  content: '';
  position: absolute;
  top: 0.72em;
  left: 0;
  width: 12px;
  height: 2px;
  background: var(--green);
}

ul.checks li strong { color: var(--ink); font-weight: 600; }

.shift,
.process-list,
.ledger-list {
  margin-top: 28px;
  border-top: 1px solid var(--rule-strong);
}

.shift-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 8px 48px;
  padding-block: 17px;
  border-bottom: 1px solid var(--rule);
}

.shift-head {
  padding-block: 10px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.shift-row p { margin: 0; }
.shift-row .today { color: var(--muted); }
.shift-row .after { color: var(--ink); }

.cell-label { display: none; }

.process-step {
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  gap: 24px 48px;
  padding-block: 24px;
  border-bottom: 1px solid var(--rule);
}

.process-step .step {
  margin: 0;
  color: var(--green);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.process-step h3 { margin-bottom: 8px; }
.process-step p { max-width: 64ch; margin: 0; color: var(--muted); }

.ledger-row {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 16px 32px;
  padding-block: 20px;
  border-bottom: 1px solid var(--rule);
}

.ledger-row h3,
.ledger-row p { margin: 0; }
.ledger-row p { color: var(--muted); }

.note-date {
  display: block;
  margin-top: 8px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* Article patterns */
.article-page .hero h1 { max-width: 19ch; font-size: clamp(38px, 6vw, 58px); }
.article-page .prose > p { max-width: 62ch; }

.quote {
  max-width: 34ch;
  margin: 28px 0;
  padding: 4px 0 4px 20px;
  border-left: 3px solid var(--rule-strong);
  font-family: 'Fraunces', Charter, Georgia, serif;
  font-size: 22px;
  font-weight: 350;
  line-height: 1.35;
}

.tech {
  max-width: 66ch;
  margin: 24px 0;
  padding: 20px 22px;
  border: 1px solid var(--rule-strong);
  border-left: 3px solid var(--green);
  background: var(--surface);
}

.tech .tag {
  margin: 0 0 10px;
  color: var(--green);
  font-family: var(--mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.tech p,
.tech li { color: var(--muted); font-size: 15px; }
.tech p:last-child { margin-bottom: 0; }
.tech ul { margin: 0; padding-left: 20px; }
.tech li { margin-bottom: 8px; }
.tech li:last-child { margin-bottom: 0; }

code {
  padding: 1px 4px;
  border: 1px solid var(--rule);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--mono);
  font-size: 0.88em;
}

figure.diagram { margin: 36px 0; }
figure.diagram svg { display: block; width: 100%; height: auto; }
figure.diagram .tall { display: none; }
figure.diagram figcaption {
  margin-top: 14px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.5;
}

.d-node { fill: var(--surface); stroke: var(--rule-strong); stroke-width: 1.5; }
.d-node-fail { fill: var(--paper); stroke: var(--rule-strong); stroke-width: 1.5; stroke-dasharray: 4 4; }
.d-node-pass { fill: var(--green); }
.d-node-future { fill: transparent; stroke: var(--green); stroke-width: 1.5; stroke-dasharray: 4 4; }
.d-title,
.d-sub,
.d-item { font-family: Charter, Georgia, serif; }
.d-label { font-family: var(--mono); }
.d-title { fill: var(--ink); font-size: 15px; font-weight: 600; }
.d-sub,
.d-item { fill: var(--muted); font-size: 12.5px; }
.d-title-pass { fill: var(--paper); }
.d-sub-pass { fill: var(--paper); opacity: 0.84; }
.d-title-future { fill: var(--green); }
.d-label { fill: var(--muted); font-size: 11px; font-weight: 500; letter-spacing: 0.06em; }
.d-label-pass { fill: var(--green); }
.d-line { fill: none; stroke: var(--muted); stroke-width: 1.25; }
.d-dash { stroke-dasharray: 3 4; }
.d-tick,
.d-gate { fill: var(--green); }

.table-scroll {
  max-width: 100%;
  margin: 24px 0;
  overflow-x: auto;
  border-block: 1px solid var(--rule-strong);
  overscroll-behavior-inline: contain;
}

table.ladder {
  width: 100%;
  min-width: 660px;
  border-collapse: collapse;
}

table.ladder th {
  padding: 10px 16px 10px 0;
  border-bottom: 1px solid var(--rule-strong);
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-align: left;
  text-transform: uppercase;
}

table.ladder td {
  padding: 14px 16px 14px 0;
  border-bottom: 1px solid var(--rule);
  color: var(--muted);
  vertical-align: top;
}

table.ladder tbody tr:last-child td { border-bottom: 0; }

table.ladder td:first-child {
  color: var(--green);
  font-family: var(--mono);
  font-size: 14px;
  white-space: nowrap;
}

/* Contact and footer */
.contact-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.7fr);
  gap: 32px 64px;
  align-items: end;
}

.contact-layout h2,
.contact-layout p { margin-bottom: 0; }
.contact-actions { justify-self: end; }

.site-footer { padding-block: 36px 52px; }

.footer-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 14px 24px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.03em;
}

.footer-row a { text-decoration: none; }

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

  body,
  .site-header,
  .nav-shell,
  .theme-toggle,
  main > section,
  .section-label::after,
  .btn,
  .shift-row,
  .process-step,
  .ledger-row,
  .tech,
  .table-scroll,
  table.ladder th,
  table.ladder td,
  .brand-mark rect,
  figure.diagram * {
    transition: background-color 200ms ease, border-color 200ms ease, color 200ms ease, fill 200ms ease, stroke 200ms ease;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation: none !important;
    transition: none !important;
  }

  .progress-index { display: none; }
}

@media (max-width: 820px) {
  :root { --header-offset: 88px; }
  .desktop-nav { display: none; }
  .mobile-nav { display: block; margin-left: auto; }

  .mobile-nav summary {
    display: flex;
    min-width: 64px;
    min-height: 44px;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--rule-strong);
    color: var(--ink);
    cursor: pointer;
    list-style: none;
  }

  .mobile-nav summary::-webkit-details-marker { display: none; }
  .mobile-nav[open] summary { border-color: var(--green); color: var(--green); }

  .mobile-nav-panel {
    position: absolute;
    top: 70px;
    right: 0;
    left: 0;
    display: grid;
    padding: 8px clamp(20px, 4vw, 32px) 16px;
    border-bottom: 1px solid var(--rule-strong);
    background: var(--paper);
  }

  .mobile-nav-panel .nav-link,
  .mobile-nav-panel .nav-cta {
    min-height: 44px;
    border-bottom: 1px solid var(--rule);
    color: var(--ink);
  }

  .mobile-nav-panel .theme-toggle {
    width: 100%;
    min-height: 44px;
    margin-top: 12px;
  }
}

@media (max-width: 720px) {
  main > section { padding-block: 48px; }
  .hero { padding-block: 64px; }
  .checks-grid { grid-template-columns: 1fr; gap: 0; }
  .shift-row { grid-template-columns: 1fr; gap: 10px; }
  .shift-head { display: none; }
  .cell-label {
    display: block;
    margin-bottom: 3px;
    color: var(--muted);
    font-family: var(--mono);
    font-size: 11px;
    letter-spacing: 0.07em;
    text-transform: uppercase;
  }
  .process-step,
  .ledger-row { grid-template-columns: 1fr; gap: 10px; }
  .contact-layout { grid-template-columns: 1fr; align-items: start; }
  .contact-actions { justify-self: start; }

  figure.diagram .wide { display: none; }
  figure.diagram .tall { display: block; max-width: 340px; margin-inline: auto; }
}

@media (max-width: 420px) {
  .brand-lockup { gap: 8px; font-size: 11.5px; letter-spacing: 0.08em; }
  .actions { align-items: stretch; flex-direction: column; }
  .actions .btn { width: 100%; }
}