/*
 * fixrb.dev, one stylesheet.
 *
 * Colours come from the logo. Edges are square and shadows have no blur:
 * a 4px "pixel" sets borders, notches and offsets. Pixelify Sans (SIL Open
 * Font License, see /fonts/OFL.txt) is a display face: it sets large titles,
 * the site name, menus and gem names only, since at small sizes its C reads
 * as an O. Everything else uses the reader's system font.
 *
 * The markup this relies on is described in README.md, under Markup.
 */

@font-face {
  font-family: "Pixelify Sans";
  src: url("/fonts/pixelify-sans.woff2") format("woff2");
  font-weight: 400 700;
  font-style: normal;
  font-display: swap;
  unicode-range: U+0020-007E, U+00A0-00FF, U+2013-2014, U+2018-201A,
    U+201C-201E, U+2022, U+2026, U+2039-203A;
}

:root {
  color-scheme: light dark;

  /* Logo palette */
  --paper: #fffef8;
  --ink: #211630;
  --wine: #510032;
  --bordeaux: #770036;
  --red: #f0013d;
  --pink: #ff496b;

  /* Roles */
  --bg: var(--paper);
  --text: var(--ink);
  --muted: #5b4a5e;
  --surface: #fbf1ee;
  --link: var(--bordeaux);
  --accent: var(--red);
  --frame: var(--ink);
  --shadow: var(--bordeaux);
  --code-bg: var(--ink);
  --code-text: var(--paper);

  /* Ruby tokens: tints of the logo's pinks and purple, at least 5:1 on
     both code backgrounds (#211630 and #0f0916). */
  --token-comment: #a597b3;
  --token-keyword: #ff496b;
  --token-constant: #ffb3c1;
  --token-string: #c9b3ff;
  --token-number: #ff8da2;
  --band: var(--wine);
  --band-text: var(--paper);
  --foot: var(--ink);

  --px: 4px;
  --display: "Pixelify Sans", ui-monospace, monospace;
  --body: system-ui, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --measure: 42rem;
  --wide: 66rem;
  --gutter: max(1rem, (100% - var(--wide)) / 2);
}

@media screen and (prefers-color-scheme: dark) {
  :root {
    --bg: #1a1126;
    --text: var(--paper);
    --muted: #c9b8cc;
    --surface: var(--ink);
    --link: #ff7a92;
    --accent: var(--pink);
    --frame: #960039;
    --shadow: var(--wine);
    --code-bg: #0f0916;
    --foot: #0f0916;
  }
}

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 1.0625rem/1.6 var(--body);
}

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

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

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

/* Site header: a wine band with a pixel fringe below it. */

body > header {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 2rem;
  margin-bottom: calc(2 * var(--px));
  padding: 1rem var(--gutter);
  background: var(--band);
  color: var(--band-text);
}

body > header::after {
  content: "";
  position: absolute;
  inset: 100% 0 auto;
  height: calc(2 * var(--px));
  background: repeating-linear-gradient(
    90deg,
    var(--band) 0 calc(2 * var(--px)),
    transparent 0 calc(4 * var(--px))
  );
}

body > header > a {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  color: inherit;
  font: 700 1.75rem/1 var(--display);
  text-decoration: none;
}

body > header > a:hover {
  background: none;
  color: inherit;
}

body > header > a img {
  width: 2.5rem;
}

nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

body > header nav a {
  display: block;
  padding: 0.375rem 0.75rem;
  color: var(--band-text);
  font: 1.125rem/1 var(--display);
  text-decoration: none;
}

body > header nav a:hover,
body > header nav a[aria-current="page"] {
  background: var(--band-text);
  color: var(--band);
}

/* Forced colours drop backgrounds: mark the current page another way. */
@media (forced-colors: active) {
  body > header nav a[aria-current="page"] {
    text-decoration: underline;
  }
}

/* Main column */

main {
  padding: 3rem var(--gutter) 5rem;
}

main :is(p, ul, ol, dl, pre, figure, hgroup, h1, h2, h3, h4) {
  max-width: var(--measure);
}

a {
  color: var(--link);
  text-decoration-thickness: 2px;
  text-underline-offset: 0.2em;
}

a:hover {
  background: var(--link);
  color: var(--bg);
  text-decoration: none;
}

a:hover code {
  background: none;
}

h1,
h2,
h3,
h4 {
  font-weight: 700;
  line-height: 1.2;
  text-wrap: balance;
  overflow-wrap: break-word;
}

h1,
h2 {
  font-family: var(--display);
  line-height: 1.15;
}

h1 {
  margin: 0 0 1rem;
  color: var(--link);
  font-size: clamp(2.25rem, 1.5rem + 3vw, 3.5rem);
}

h2 {
  margin: 3.5rem 0 1rem;
  font-size: 1.875rem;
}

h2::before {
  content: "";
  display: inline-block;
  width: 0.5em;
  height: 0.5em;
  margin-right: 0.5em;
  background: var(--accent);
  box-shadow: var(--px) var(--px) 0 var(--shadow);
}

h3 {
  margin: 2.25rem 0 0.75rem;
  font-size: 1.25rem;
}

hgroup p {
  margin: 0;
  color: var(--muted);
  font-size: 1.25rem;
  line-height: 1.4;
  overflow-wrap: break-word;
}

ul {
  list-style: square;
}

li::marker {
  color: var(--accent);
}

main li + li {
  margin-top: 0.25rem;
}

dl {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 0.375rem 1.5rem;
}

dt {
  color: var(--muted);
  font-weight: 600;
}

dd {
  margin: 0;
}

@media (max-width: 34rem) {
  dl {
    grid-template-columns: 1fr;
    row-gap: 0;
  }

  dd {
    margin-bottom: 0.75rem;
  }
}

/* Code: a dark slab with notched pixel corners. Long lines wrap, so that
   nothing hides behind a scroll bar, on screen or on paper. */

code,
kbd,
samp {
  font-family: var(--mono);
  font-size: 0.875em;
}

:not(pre) > code {
  padding: 0.125em 0.25em;
  background: var(--surface);
}

pre {
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  margin: 1.75rem var(--px);
  padding: 1rem clamp(1rem, 3vw, 1.25rem);
  background: var(--code-bg);
  color: var(--code-text);
  font-size: 0.875rem;
  line-height: 1.55;
  box-shadow:
    0 calc(-1 * var(--px)) 0 var(--code-bg),
    0 var(--px) 0 var(--code-bg),
    calc(-1 * var(--px)) 0 0 var(--code-bg),
    var(--px) 0 0 var(--code-bg);
}

pre code,
pre samp,
pre kbd {
  font-size: inherit;
}

/* In a terminal session, what was typed. */
pre kbd {
  font-weight: 700;
}

/* The only classes of the site: Ruby tokens, written by bin/check --fix. */
pre .comment {
  color: var(--token-comment);
}

pre .keyword {
  color: var(--token-keyword);
}

pre .constant {
  color: var(--token-constant);
}

pre .string {
  color: var(--token-string);
}

pre .number {
  color: var(--token-number);
}

figure {
  margin: 2rem 0;
}

figcaption {
  margin-top: 1rem;
  color: var(--muted);
  font-size: 0.9375rem;
}

[role="note"] {
  padding: 1rem 1.25rem;
  border-left: calc(2 * var(--px)) solid var(--accent);
  background: var(--surface);
}

/* Home: introduction */

#intro {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  gap: 1.5rem 2rem;
}

#intro > img {
  width: clamp(5rem, 4rem + 6vw, 8rem);
}

#intro > hgroup h1 {
  margin-bottom: 0.5rem;
}

#intro > :is(p, figure, ul) {
  grid-column: 1 / -1;
  margin: 0;
}

#intro > ul {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.5rem;
  padding: 0;
  list-style: none;
}

#intro > ul li {
  margin: 0;
}

#intro > ul a {
  display: inline-block;
  padding: 0.625rem 1rem;
  /* Invisible, except in forced colours, where backgrounds are dropped. */
  border: 2px solid transparent;
  background: var(--link);
  color: var(--bg);
  font: 1.125rem/1 var(--display);
  text-decoration: none;
  box-shadow: var(--px) var(--px) 0 var(--frame);
}

#intro > ul a:hover {
  background: var(--text);
  color: var(--bg);
}

#intro > ul a:active {
  translate: var(--px) var(--px);
  box-shadow: none;
}

@media (min-width: 62rem) {
  #intro {
    grid-template-columns: auto minmax(0, 1fr) minmax(0, 27rem);
    grid-template-rows: auto auto auto 1fr;
    align-items: start;
    column-gap: 3rem;
  }

  #intro > :is(img, hgroup) {
    align-self: center;
  }

  #intro > :is(p, ul) {
    grid-column: 1 / 3;
  }

  #intro > figure {
    grid-column: 3;
    grid-row: 1 / -1;
  }
}

/* Cards: the gem list and the post lists */

#stack > ul,
#others > ul {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 18rem), 1fr));
  gap: 2rem 1.75rem;
  max-width: none;
  padding: 0;
  list-style: none;
}

#stack > ul > li,
#others > ul > li {
  display: flex;
  flex-direction: column;
  margin: 0 calc(3 * var(--px)) calc(3 * var(--px)) var(--px);
  padding: 1.25rem 1.25rem 1rem;
  background: var(--surface);
  box-shadow:
    0 calc(-1 * var(--px)) 0 var(--frame),
    0 var(--px) 0 var(--frame),
    calc(-1 * var(--px)) 0 0 var(--frame),
    var(--px) 0 0 var(--frame),
    calc(3 * var(--px)) calc(3 * var(--px)) 0 var(--shadow);
}

#stack h4,
#others h4 {
  margin: 0 0 0.5rem;
  font-family: var(--display);
  font-size: 1.5rem;
}

#stack li p,
#others li p {
  margin: 0;
}

#stack li p:has(> small) {
  margin-top: auto;
  padding-top: 0.75rem;
}

li small {
  color: var(--link);
  font-size: 0.9375rem;
  font-weight: 600;
}

li > article h2,
li > article h3 {
  margin: 0;
  font-family: var(--body);
  font-size: 1.25rem;
}

li > article h2::before {
  content: none;
}

li > article p {
  margin: 0.25rem 0 0;
}

li > article p:first-of-type {
  color: var(--muted);
}

main ul:has(> li > article) {
  padding: 0;
  list-style: none;
}

main ul:has(> li > article) > li + li {
  margin-top: 1.75rem;
}

/* Articles */

article > header p {
  margin: 0;
  color: var(--muted);
}

article > footer {
  margin-top: 3.5rem;
  padding-top: 1.5rem;
  border-top: var(--px) dashed var(--muted);
  color: var(--muted);
}

/* Site footer */

body > footer {
  position: relative;
  margin-top: calc(2 * var(--px));
  padding: 2rem var(--gutter);
  background: var(--foot);
  color: var(--paper);
  font-size: 0.9375rem;
}

body > footer::before {
  content: "";
  position: absolute;
  inset: auto 0 100%;
  height: calc(2 * var(--px));
  background: repeating-linear-gradient(
    90deg,
    var(--foot) 0 calc(2 * var(--px)),
    transparent 0 calc(4 * var(--px))
  );
}

body > footer p {
  margin: 0 0 1rem;
}

body > footer ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--display);
}

body > footer li {
  margin: 0;
}

body > footer a {
  color: var(--paper);
}

body > footer a:hover {
  background: var(--paper);
  color: var(--ink);
}

/* Paper: the light theme, with its dark slabs and bands kept. */
@media print {
  html {
    -webkit-print-color-adjust: exact;
    print-color-adjust: exact;
  }
}