/* origin — one stylesheet, hand written.
   Order: tokens, fonts, reset, layout, blocks, prose, code, motion. */

/* ---------------------------------------------------------------- tokens */

:root {
  /* paper — drafting paper, not cream */
  --bg:        #E9ECE6;
  --surface:   #F3F5F0;
  --ink:       #171A17;
  --muted:     #565C54;
  --rule:      #C6CCC2;
  --signal:    #8A5A11;
  --signal-ui: #A8701F;

  --font-text: "Public Sans", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-code: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  /* scale from 16px */
  --t-xs:  0.875rem;
  --t-s:   1rem;
  --t-m:   1.125rem;
  --t-l:   1.375rem;
  --t-xl:  1.75rem;
  --t-2xl: 2.25rem;

  --measure: 68ch;
  --rail:    11rem;
  --gutter:  1.25rem;

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4.5rem;
}

/* phosphor — amber terminal on slate. Declared twice on purpose: once for a
   reader who has never chosen, once for a reader who has. */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="paper"]) {
    --bg:        #161B23;
    --surface:   #1D2430;
    --ink:       #DDE3E0;
    --muted:     #98A29B;
    --rule:      #2B333D;
    --signal:    #E0AC4E;
    --signal-ui: #E0AC4E;
  }
}

:root[data-theme="phosphor"] {
  --bg:        #161B23;
  --surface:   #1D2430;
  --ink:       #DDE3E0;
  --muted:     #98A29B;
  --rule:      #2B333D;
  --signal:    #E0AC4E;
  --signal-ui: #E0AC4E;
}

/* ----------------------------------------------------------------- fonts */

@font-face {
  font-family: "Public Sans";
  src: url("/static/fonts/public-sans-var.woff2") format("woff2");
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

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

/* ----------------------------------------------------------------- reset */

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

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

@media (prefers-color-scheme: dark) {
  html:not([data-theme="paper"]) { color-scheme: dark; }
}

html[data-theme="phosphor"] { color-scheme: dark; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-text);
  font-size: var(--t-s);
  line-height: 1.6;
  font-synthesis-weight: none;
  text-rendering: optimizeLegibility;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

h1, h2, h3, h4, p, ul, ol, dl, dd, figure, pre, blockquote { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img { max-width: 100%; height: auto; }

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

a:hover { text-decoration-color: var(--signal); }

:focus-visible {
  outline: 2px solid var(--signal-ui);
  outline-offset: 2px;
  border-radius: 1px;
}

::selection { background: var(--signal-ui); color: var(--bg); }

.skip {
  position: absolute;
  left: -9999px;
  top: var(--space-2);
  padding: var(--space-2) var(--space-3);
  background: var(--surface);
  border: 1px solid var(--rule);
  z-index: 2;
}

.skip:focus { left: var(--space-4); }

/* ---------------------------------------------------------------- layout */

.shell {
  width: min(100% - (var(--gutter) * 2), 46rem);
  margin-inline: auto;
}

main.shell { flex: 1 0 auto; padding-bottom: var(--space-8); }

/* The one grid the whole site uses: metadata in the left margin, content in
   the measure. Everything lines up on the same two verticals. */
.row { display: block; }
.row__rail { display: block; color: var(--muted); font-size: var(--t-xs); }
.row__main { min-width: 0; }

@media (min-width: 48rem) {
  .row {
    display: grid;
    grid-template-columns: var(--rail) minmax(0, var(--measure));
    align-items: baseline;
  }
  .row__rail { padding-right: var(--space-4); }
}

/* -------------------------------------------------------------- masthead */

.masthead { padding-top: var(--space-6); padding-bottom: var(--space-5); }

.masthead__top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-4);
}

.masthead__name {
  font-size: var(--t-m);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.masthead--home .masthead__name { font-size: var(--t-l); }
.masthead__name a { text-decoration: none; }
.masthead__name a:hover { text-decoration: underline; text-decoration-color: var(--signal); }

.nav { margin-top: var(--space-4); }

.nav__list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  font-size: var(--t-xs);
}

.nav__link {
  color: var(--muted);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
}

.nav__link:hover { color: var(--ink); border-bottom-color: var(--rule); }

.nav__link[aria-current="page"] {
  color: var(--ink);
  border-bottom-color: var(--signal);
}

/* The toggle is the whole personality budget, spent in one place. It needs
   JavaScript, so it is not shown to a reader who has none. */
.toggle { display: none; }

[data-js] .toggle {
  display: inline-flex;
  align-items: baseline;
  gap: var(--space-1);
  background: none;
  border: 0;
  padding: var(--space-1) 0;
  margin: 0;
  color: var(--muted);
  font: inherit;
  font-size: var(--t-xs);
  cursor: pointer;
  white-space: nowrap;
}

.toggle__slash { color: var(--rule); }
.toggle__option[data-current] { color: var(--signal); }
.toggle:hover .toggle__option:not([data-current]) { color: var(--ink); }

/* ----------------------------------------------------------------- intro */

.intro {
  max-width: var(--measure);
  margin-bottom: var(--space-7);
  color: var(--muted);
  font-size: var(--t-m);
  text-wrap: pretty;
}

.intro p + p { margin-top: var(--space-1); }

/* ------------------------------------------------------------------- log */

.log__year + .log__year { margin-top: var(--space-6); }

.log__label,
.list__label {
  font-size: var(--t-xs);
  font-weight: 500;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
  padding-bottom: var(--space-2);
  border-bottom: 1px solid var(--rule);
  margin-bottom: var(--space-4);
}

.log__item,
.list__item {
  padding-block: var(--space-2);
}

.log__item + .log__item,
.list__item + .list__item { margin-top: var(--space-1); }

.list--spaced .list__item + .list__item,
.list--grid .list__item + .list__item { margin-top: var(--space-4); }

.log__date,
.list__date {
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

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

.log__item .row__rail {
  display: flex;
  gap: var(--space-2);
}

@media (min-width: 48rem) {
  .log__item .row__rail {
    display: grid;
    grid-template-columns: 4.5rem minmax(0, 1fr);
    column-gap: var(--space-2);
  }
}

.log__title,
.list__title {
  display: inline-block;
  text-decoration: none;
  text-wrap: pretty;
}

.log__title:hover,
.list__title:hover {
  text-decoration: underline;
  text-decoration-color: var(--signal);
}

.log__note,
.list__note,
.list__summary {
  display: block;
  color: var(--muted);
  font-size: var(--t-xs);
}

.list__summary { text-wrap: pretty; margin-top: var(--space-1); }
.list__note { margin-top: var(--space-1); }
.log__note { margin-top: 0; }

/* --------------------------------------------------------------- listings */

.list__group + .list__group { margin-top: var(--space-6); }
.list--dense .list__group + .list__group { margin-top: var(--space-5); }

.status {
  display: inline-block;
  color: var(--muted);
}

.status--live { color: var(--ink); }

.stack {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-3);
  margin-top: var(--space-2);
}

.stack__item {
  font-family: var(--font-code);
  font-size: var(--t-xs);
  color: var(--muted);
}

/* ------------------------------------------------------------------ rail */

.row--entry { margin-top: var(--space-5); align-items: start; }

.rail__list { font-size: var(--t-xs); color: var(--muted); }

.rail__pair + .rail__pair { margin-top: var(--space-3); }

.rail__pair dt {
  color: var(--muted);
  opacity: 0.75;
}

.rail__pair dd { margin: 0; color: var(--ink); }
.rail__pair dd time { font-variant-numeric: tabular-nums; }

.rail__stack { display: flex; flex-wrap: wrap; gap: var(--space-1) var(--space-2); }
.rail__stack code { font-family: var(--font-code); font-size: 0.8125rem; }

@media (max-width: 47.99rem) {
  .rail__list {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2) var(--space-4);
  }
  .rail__pair { display: flex; gap: var(--space-2); }
  .rail__pair + .rail__pair { margin-top: 0; }
}

/* ----------------------------------------------------------------- entry */

.entry__title {
  font-size: var(--t-xl);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.015em;
  text-wrap: balance;
  max-width: var(--measure);
}

.entry__summary {
  margin-top: var(--space-3);
  color: var(--muted);
  font-size: var(--t-m);
  max-width: var(--measure);
  text-wrap: pretty;
}

/* ----------------------------------------------------------------- prose */

.prose {
  margin-top: var(--space-6);
  max-width: var(--measure);
  text-wrap: pretty;
}

.prose > * + * { margin-top: var(--space-4); }

.prose h2 {
  font-size: var(--t-m);
  font-weight: 600;
  margin-top: var(--space-7);
  letter-spacing: -0.005em;
}

.prose h3 {
  font-size: var(--t-s);
  font-weight: 600;
  margin-top: var(--space-6);
}

.prose h2 + *, .prose h3 + * { margin-top: var(--space-3); }

.prose a { text-decoration-color: var(--muted); }

.prose ul, .prose ol {
  padding-left: var(--space-5);
  list-style: disc;
}

.prose ol { list-style: decimal; }
.prose li + li { margin-top: var(--space-2); }
.prose li::marker { color: var(--muted); }

.prose blockquote {
  padding-left: var(--space-4);
  border-left: 2px solid var(--rule);
  color: var(--muted);
}

.prose hr {
  border: 0;
  border-top: 1px solid var(--rule);
  margin-block: var(--space-6);
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--t-xs);
}

.prose th, .prose td {
  text-align: left;
  padding: var(--space-2) var(--space-3) var(--space-2) 0;
  border-bottom: 1px solid var(--rule);
}

.prose th { font-weight: 600; }

/* ------------------------------------------------------------------ code */

.prose code {
  font-family: var(--font-code);
  font-size: 0.875em;
  background: var(--surface);
  padding: 0.1em 0.3em;
  border-radius: 2px;
}

.prose pre {
  overflow-x: auto;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 3px;
  padding: var(--space-4);
  font-family: var(--font-code);
  font-size: var(--t-xs);
  line-height: 1.55;
  tab-size: 4;
}

.prose pre code {
  background: none;
  padding: 0;
  font-size: inherit;
}

/* Highlighting is monochrome. Colour on this site means one thing, and code
   is not it. Weight and italic carry the structure instead. */
.chroma .c, .chroma .ch, .chroma .cm, .chroma .c1, .chroma .cs, .chroma .cp, .chroma .cpf {
  color: var(--muted);
  font-style: italic;
}

.chroma .k, .chroma .kc, .chroma .kd, .chroma .kn, .chroma .kp, .chroma .kr, .chroma .kt {
  font-weight: 600;
}

.chroma .s, .chroma .sa, .chroma .sb, .chroma .sc, .chroma .dl, .chroma .sd, .chroma .s2,
.chroma .se, .chroma .sh, .chroma .si, .chroma .sx, .chroma .sr, .chroma .s1, .chroma .ss,
.chroma .m, .chroma .mb, .chroma .mf, .chroma .mh, .chroma .mi, .chroma .il, .chroma .mo {
  color: var(--muted);
}

.chroma .nf, .chroma .nc, .chroma .nb { font-weight: 500; }
.chroma .err { color: inherit; background: none; }

/* --------------------------------------------------------------- pointer */

.pointer--prev-next {
  display: grid;
  gap: var(--space-4);
  margin-top: var(--space-8);
  font-size: var(--t-xs);
}

@media (min-width: 40rem) {
  .pointer--prev-next { grid-template-columns: 1fr 1fr; gap: var(--space-5); }
  .pointer__side--end { text-align: right; }
}

.pointer__label {
  display: block;
  color: var(--muted);
  margin-bottom: var(--space-1);
}

.pointer__side a { text-wrap: pretty; }

.pointer__list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  font-size: var(--t-xs);
}

.pointer__list a { color: var(--muted); text-decoration: none; }
.pointer__list a:hover { color: var(--ink); text-decoration: underline; text-decoration-color: var(--signal); }
.pointer__list a[aria-current="page"] { color: var(--ink); }

/* ---------------------------------------------------------------- notice */

.notice {
  max-width: var(--measure);
  padding: var(--space-5) 0;
}

.notice__title {
  font-family: var(--font-code);
  font-size: var(--t-xs);
  color: var(--muted);
  margin-bottom: var(--space-2);
}

.notice__body { font-size: var(--t-m); }

/* ---------------------------------------------------------------- footer */

.footer {
  margin-top: auto;
  padding-block: var(--space-5) var(--space-7);
  border-top: 1px solid var(--rule);
  font-size: var(--t-xs);
}

.colophon {
  margin-top: var(--space-4);
  max-width: var(--measure);
  color: var(--muted);
  text-wrap: pretty;
}

.colophon a { color: var(--muted); }
.colophon a:hover { color: var(--ink); }

.contact { margin-top: var(--space-2); }
.footer .contact { color: var(--muted); }
.footer .contact a { color: var(--muted); }
.footer .contact a:hover { color: var(--ink); }

.row__main > .contact {
  margin-top: var(--space-6);
  font-size: var(--t-s);
}

/* ---------------------------------------------------------------- motion */

/* Motion answers actions. There is one animation on this site and this is it. */
@media (prefers-reduced-motion: no-preference) {
  body { transition: background-color 120ms linear, color 120ms linear; }
  .toggle__option, .nav__link, a { transition: color 120ms linear; }
}