/* adamgayoso.com */

:root {
  --bg:     #fffff8;
  --text:   #111111;
  --muted:  #6f6759;
  --accent: #a46f0d;
  --rule:   #e2ded0;
  --surface: #faf8ec;
  --chip:    #f2efe1;
  --err:     #b3402b;

  --serif: Charter, "Bitstream Charter", "Sitka Text", Cambria, Georgia, serif;
  --mono: ui-monospace, "SF Mono", "IBM Plex Mono", Menlo, Consolas, monospace;

  --measure: 38rem;
  --margin-col: 15rem;
  --gutter: 2rem;
}

/* Three states: no attribute follows the OS, [data-theme] wins either way.
   The dark palette is written twice on purpose -- plain CSS has no way to
   share a declaration block between a media query and an attribute
   selector. */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg:     #14120e;
    --text:   #e9e4d8;
    --muted:  #9a9284;
    --accent: #d9a748;
    --rule:   #302b22;
    --surface: #1c1915;
    --chip:    #26221a;
    --err:     #e08163;
  }
}

:root[data-theme="dark"] {
  --bg:     #14120e;
  --text:   #e9e4d8;
  --muted:  #9a9284;
  --accent: #d9a748;
  --rule:   #302b22;
  --surface: #1c1915;
  --chip:    #26221a;
  --err:     #e08163;
}

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--serif);
  font-size: 1.25rem;
  line-height: 1.55;
  font-kerning: normal;
  font-variant-ligatures: common-ligatures;
  text-rendering: optimizeLegibility;
  /* Old-style figures: numerals sit in the line rather than above it. Charter
     and Georgia both have them; code and chips opt back out below. */
  font-variant-numeric: oldstyle-nums;
}

code, kbd, samp, pre, .aux, .cell-input, .cell-output, .cell-html {
  font-variant-numeric: normal;
}

/* Tufte uses italics and small caps rather than bold for emphasis. */
h1, h2, h3 {
  font-weight: 400;
  line-height: 1.2;
  letter-spacing: -0.005em;
}

h1 {
  font-size: 2.1rem;
  margin: 0 0 1.6rem;
}

h2 {
  font-style: italic;
  font-size: 1.45rem;
  margin: 2.8rem 0 0.8rem;
}

h3 {
  font-style: italic;
  font-size: 1.15rem;
  margin: 2rem 0 0.6rem;
}

p, li {
  /* Avoids a single word orphaned on the last line. Ignored where
     unsupported, so there is nothing to fall back to. */
  text-wrap: pretty;
}

p { margin: 0 0 1.2rem; }

a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid color-mix(in srgb, var(--accent) 35%, transparent);
}

a:hover {
  border-bottom-color: var(--accent);
}

/* Body copy keeps its text colour and marks links with an amber rule only.
   At this link density, amber text everywhere speckles the paragraph. The
   :not(.aux) keeps the code/docs chips out of it. */
.prose a:not(.aux), article a:not(.aux) {
  color: inherit;
  border-bottom: 1px solid var(--accent);
}

.prose a:not(.aux):hover, article a:not(.aux):hover {
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 10%, transparent);
}

strong { font-weight: 600; }

hr {
  border: 0;
  border-top: 1px solid var(--rule);
  margin: 2.5rem 0;
}

sup { line-height: 0; }

code, kbd, samp {
  font-family: var(--mono);
  font-size: 0.84em;
}

blockquote {
  margin: 1.5rem 0;
  padding-left: 1.2rem;
  border-left: 2px solid var(--rule);
  font-style: italic;
  color: var(--muted);
}

ul, ol { margin: 0 0 1.2rem; padding-left: 1.4rem; }
li { margin-bottom: 0.35rem; }

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

main { padding: 4.5rem 1.5rem 0; }

body.home main {
  max-width: calc(var(--measure) + 3rem);
  margin: 0 auto;
}

/* Posts use the asymmetric Tufte measure: text left, notes and wide figures
   in the right margin. */
body.post main {
  max-width: calc(var(--measure) + var(--gutter) + var(--margin-col) + 3rem);
  margin: 0 auto;
}

body.post article > * {
  max-width: var(--measure);
}

.prose > :last-child, article > :last-child { margin-bottom: 0; }

.back {
  font-size: 0.85rem;
  font-style: italic;
  margin-bottom: 2rem;
}

.back a { color: var(--muted); border-bottom-color: transparent; }
.back a:hover { color: var(--accent); }

.byline {
  color: var(--muted);
  font-style: italic;
  font-size: 0.95rem;
  margin: -1rem 0 2.2rem;
}

/* Secondary links -- code, docs -- next to a primary citation link. A filled
   chip, kept in the typographic register by small mono type and a 3px radius
   rather than a pill shape. Contrast checked in both themes (4.8:1 light,
   5.1:1 dark). */
.aux {
  font-family: var(--mono);
  font-size: 0.68em;
  letter-spacing: 0.03em;
  color: var(--muted);
  background: var(--chip);
  border: 0;
  border-bottom: 0;
  border-radius: 3px;
  padding: 0.2em 0.5em;
  margin-left: 0.25em;
  white-space: nowrap;
  vertical-align: 0.1em;
}

.aux:hover {
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 12%, var(--chip));
}

/* .prose zeroes its last child's margin, so a listing following an intro
   paragraph needs its own gap. */
.prose + .listing { margin-top: 2rem; }

/* ----------------------------------------------------------------- listing */

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

.listing li {
  margin: 0 0 1.5rem;
  display: flex;
  flex-direction: column;
}

.listing li > a { border-bottom-color: transparent; }
.listing li > a:hover { border-bottom-color: var(--accent); }

.listing .date {
  order: -1;
  font-size: 0.8rem;
  color: var(--muted);
  letter-spacing: 0.02em;
}

.listing .summary {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.45;
  margin-top: 0.15rem;
}

/* --------------------------------------------------------------- sidenotes */

/* Written as ordinary [^1] markdown footnotes; build.py relocates them. */
.sidenote-number {
  counter-increment: sidenote;
  display: inline;
}

.sidenote-number::after {
  content: counter(sidenote);
  font-size: 0.7rem;
  vertical-align: super;
  line-height: 0;
  color: var(--accent);
  cursor: pointer;
  padding-left: 0.1em;
}

body { counter-reset: sidenote; }

.sidenote {
  float: right;
  clear: right;
  width: var(--margin-col);
  margin-right: calc(-1 * (var(--margin-col) + var(--gutter)));
  margin-top: 0.35rem;
  margin-bottom: 1rem;
  font-size: 0.88rem;
  line-height: 1.4;
  color: var(--muted);
  position: relative;
}

.sidenote::before {
  content: counter(sidenote) " ";
  font-size: 0.7rem;
  vertical-align: super;
  line-height: 0;
  color: var(--accent);
}

/* The checkbox only does anything at narrow widths. */
input.margin-toggle { display: none; }

/* ----------------------------------------------------------------- figures */

figure {
  margin: 2rem 0;
  max-width: var(--measure);
}

figure img { max-width: 100%; height: auto; display: block; }

figcaption {
  font-size: 0.85rem;
  line-height: 1.4;
  color: var(--muted);
  margin-top: 0.5rem;
}

figure.fullwidth {
  max-width: calc(var(--measure) + var(--gutter) + var(--margin-col));
}

figure.margin-figure {
  float: right;
  clear: right;
  width: var(--margin-col);
  max-width: var(--margin-col);
  margin-right: calc(-1 * (var(--margin-col) + var(--gutter)));
  margin-top: 0.35rem;
}

/* Video. Until it is clicked this is a thumbnail and a play button, so the
   page loads nothing from YouTube; the button swaps in the real player. */
.video {
  position: relative;
  margin: 1.8rem 0;
  aspect-ratio: 16 / 9;
  background: var(--chip);
  overflow: hidden;
  border-radius: 3px;
}

.video-play {
  display: block;
  width: 100%;
  height: 100%;
  padding: 0;
  border: 0;
  background: none;
  cursor: pointer;
}

.video-play img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.video-icon {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 3.4rem;
  height: 3.4rem;
  margin: -1.7rem 0 0 -1.7rem;
  border-radius: 50%;
  background: color-mix(in srgb, var(--accent) 92%, black);
  box-shadow: 0 1px 10px rgb(0 0 0 / 0.3);
}

/* The play triangle, drawn with borders so there is no icon to download. */
.video-icon::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  margin: -0.6rem 0 0 -0.35rem;
  border-style: solid;
  border-width: 0.6rem 0 0.6rem 1rem;
  border-color: transparent transparent transparent #fffff8;
}

.video-play:hover .video-icon { background: var(--accent); }
.video-play:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

article iframe {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  border: 0;
  margin: 1.8rem 0;
  background: var(--chip);
}

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

.cell { margin: 1.6rem 0; }

.cell-input, pre.cell-text, pre.cell-stderr, .highlight pre {
  font-family: var(--mono);
  font-size: 0.8rem;
  line-height: 1.5;
  overflow-x: auto;
}

.cell-input {
  border-left: 2px solid var(--accent);
  background: var(--surface);
}

.cell-input .highlight, .cell-input pre {
  margin: 0;
  padding: 0.7rem 0.9rem;
  background: transparent !important;
}

.cell-output { margin-top: 0.5rem; }

pre.cell-text, pre.cell-stderr {
  margin: 0;
  padding: 0.7rem 0.9rem;
  color: var(--muted);
  white-space: pre-wrap;
  word-break: break-word;
}

pre.cell-stderr { color: var(--err); }

.cell-image { max-width: 100%; height: auto; }

.cell-html { overflow-x: auto; font-size: 0.85rem; }

.cell-html table {
  border-collapse: collapse;
  font-family: var(--mono);
  font-size: 0.75rem;
}

.cell-html th, .cell-html td {
  padding: 0.2rem 0.6rem 0.2rem 0;
  text-align: left;
  border: 0;
}

.cell-html thead th { border-bottom: 1px solid var(--rule); }

/* ------------------------------------------------------------------- notes */

aside.note {
  margin: 1.8rem 0;
  padding: 0.9rem 1.1rem;
  background: var(--surface);
  border-left: 2px solid var(--rule);
  font-size: 0.95rem;
}

aside.note > :last-child { margin-bottom: 0; }

aside.note .aside-title {
  font-style: italic;
  color: var(--muted);
  margin-bottom: 0.4rem;
}

/* -------------------------------------------------------------------- math */

.math-block { overflow-x: auto; margin: 1.5rem 0; }

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

footer {
  max-width: calc(var(--measure) + 3rem);
  margin: 5rem auto 0;
  padding: 1.4rem 1.5rem 3rem;
  border-top: 1px solid var(--rule);
  font-size: 0.85rem;
  color: var(--muted);
}

body.post footer {
  max-width: calc(var(--measure) + var(--gutter) + var(--margin-col) + 3rem);
}


footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0 1.3rem;
  margin-bottom: 0.5rem;
}

footer nav a, footer .contact {
  color: var(--muted);
  border-bottom-color: transparent;
}

footer nav a:hover { color: var(--accent); }

footer .contact { margin: 0; }
footer .contact span { opacity: 0.55; }

/* ------------------------------------------------------------------ narrow */

@media (max-width: 1000px) {
  /* Not enough room for a margin column: sidenotes and margin figures fold
     back into the text, revealed by tapping their number. Collapsed notes are
     hidden visually rather than with display:none, so a screen reader still
     reads each one in place after its reference. */
  .sidenote, figure.margin-figure {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
  }

  .margin-toggle:checked + .sidenote,
  .margin-toggle:checked + figure.margin-figure {
    position: static;
    width: auto;
    height: auto;
    overflow: visible;
    clip-path: none;
    white-space: normal;
    float: none;
    max-width: 100%;
    margin: 1rem 0;
    padding: 0.8rem 1rem;
    background: var(--surface);
    border-left: 2px solid var(--rule);
  }

  /* A superscript digit is too small to hit with a thumb, so on touch widths
     the number becomes a small inline-block pill instead. */
  .sidenote-number::after {
    display: inline-block;
    min-width: 1.5rem;
    padding: 0.4rem 0;
    margin: -0.4rem 0;
    font-size: 0.8rem;
    line-height: 1;
    text-align: center;
    vertical-align: baseline;
  }

  /* With no margin column, the post container narrows and centres like the
     homepage -- otherwise the measure would stretch to ~75ch on an iPad held
     in portrait. */
  body.post main { max-width: calc(var(--measure) + 3rem); }
  figure.fullwidth { max-width: 100%; }
  body.post article > * { max-width: 100%; }
}

@media (max-width: 700px) {
  body { font-size: 1.15rem; }
  main { padding: 3rem 1.25rem 0; }
  h1 { font-size: 1.8rem; }
  footer { padding-left: 1.25rem; padding-right: 1.25rem; }
}

/* ------------------------------------------------------------------ theme */

#theme-toggle {
  position: fixed;
  top: 1.1rem;
  right: 1.1rem;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.1rem;
  height: 2.1rem;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

#theme-toggle:hover {
  color: var(--accent);
  background: var(--chip);
}

#theme-toggle:focus-visible {
  outline: 1px solid var(--accent);
  outline-offset: 2px;
}

#theme-toggle svg {
  width: 1.05rem;
  height: 1.05rem;
  display: block;
}

/* Show the icon for the theme you would switch TO. Same three states as the
   palette: bare :root is light, the media query covers "following the OS",
   and [data-theme] overrides both. */
#theme-toggle .icon-sun { display: none; }
#theme-toggle .icon-moon { display: block; }

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) #theme-toggle .icon-moon { display: none; }
  :root:not([data-theme="light"]) #theme-toggle .icon-sun { display: block; }
}

:root[data-theme="dark"] #theme-toggle .icon-moon { display: none; }
:root[data-theme="dark"] #theme-toggle .icon-sun { display: block; }
:root[data-theme="light"] #theme-toggle .icon-moon { display: block; }
:root[data-theme="light"] #theme-toggle .icon-sun { display: none; }

@media (max-width: 700px) {
  #theme-toggle { top: 0.6rem; right: 0.6rem; }
}