/* Layout and type modeled on mechanize.work: narrow column, no decoration. Font and colors modeled on metr.org. */

/* ===== Colors: light mode =====
   Every color on the site comes from these variables, so anything you add
   (paragraphs, lists, links, quotes, tables, code) switches with the theme. */
:root {
  color-scheme: light;
  --bg: #FFFFFF;
  --text: #4D5561;
  --heading: #1F2328;
  --link: #1F2328;                   /* links: same near-black as headings */
  --rule: rgba(0, 0, 0, 0.12);       /* <hr>, table and quote borders */
  --code-bg: #F3F5F9;

  /* Post page header band */
  --header-bg: rgba(20, 27, 45, 0.85); /* dark ink at 85% */
  --header-text: #D3D9E5;    /* page links, date, share buttons */
  --header-heading: #FFFFFF; /* Rotifer + post title */
  --header-label: #9AA6BC;   /* LAST UPDATED / SHARE */

  /* Citation popup */
  --popup-bg: #FFFFFF;
  --popup-heading: #222A34;
  --button: #2B4C8C;
}

/* ===== Colors: dark mode =====
   Used when the toggle is set to dark, or when the visitor's system is dark
   and they haven't picked. Keep the two blocks below identical. */
:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #1B1E24;
  --text: #BFC6D2;
  --heading: #EEF1F6;
  --link: #EEF1F6;
  --rule: rgba(255, 255, 255, 0.14);
  --code-bg: #262A33;
  --header-bg: rgba(20, 27, 45, 0.25); /* dark ink at 25% */
  --popup-bg: #232731;
  --popup-heading: #EEF1F6;
  --button: #3A64B5;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #1B1E24;
    --text: #BFC6D2;
    --heading: #EEF1F6;
    --link: #EEF1F6;
    --rule: rgba(255, 255, 255, 0.14);
    --code-bg: #262A33;
    --header-bg: rgba(20, 27, 45, 0.25);
    --popup-bg: #232731;
    --popup-heading: #EEF1F6;
    --button: #3A64B5;
  }
}

html {
  scrollbar-gutter: stable;
  background: var(--bg);
}

body {
  font-family: "Instrument Sans", -apple-system, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  font-size: 16px;
  padding: 0 10px;
  margin: 50px auto;
  max-width: 650px;
}

main {
  max-width: 42em;
  margin: 70px auto 15px;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--heading);
}

/* Links stay one color: no change after visiting, hovering or clicking */
a,
a:visited,
a:hover,
a:active {
  color: var(--link);
}

hr {
  border: none;
  border-top: 1px solid var(--rule);
}

blockquote {
  margin: 1em 0;
  padding-left: 1em;
  border-left: 3px solid var(--rule);
}

table {
  border-collapse: collapse;
}

th, td {
  border: 1px solid var(--rule);
  padding: 0.35em 0.6em;
}

pre, code {
  font-family: "Fira Code", Monaco, Consolas, monospace;
  font-size: 0.875em;
}

pre, :not(pre) > code {
  background: var(--code-bg);
  border-radius: 4px;
}

pre {
  padding: 1rem;
  overflow-x: auto;
}

:not(pre) > code {
  padding: 0.1em 0.3em;
}

.site-title {
  margin-bottom: 0.3em;
}

.site-nav {
  margin-bottom: 1.5em;
}

.tagline {
  margin-top: 0;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 20px auto;
}

a.plain-link {
  color: inherit;
  text-decoration: none;
}

a.plain-link:hover {
  text-decoration: underline;
}

/* ===== Light/dark toggle (sits at the end of the page links) ===== */
.theme-toggle {
  background: none;
  border: none;
  padding: 0;
  margin-left: 0.4em;
  font: inherit;
  color: inherit;
  cursor: pointer;
  vertical-align: -0.15em;
  opacity: 0.75;
  transition: opacity 0.2s ease;
}

.theme-toggle:hover {
  opacity: 1;
}

.theme-toggle svg {
  width: 1em;
  height: 1em;
  display: block;
}

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

/* ===== Post pages (work.html) =====
   Header layout modeled on metr.org. Colors are set at the top of this file. */

html {
  overflow-x: clip; /* lets the header band span the full window */
}

/* Band starts at the very top of the window on post pages */
body.post-page {
  margin-top: 0;
}

.post-header {
  /* Break out of the 650px column so the band spans the full window */
  margin: 0 calc(50% - 50vw);
  padding: 70px 20px 0;
  background: linear-gradient(to bottom,
    var(--header-bg) 0%,
    var(--header-bg) calc(100% - 40px),
    color-mix(in srgb, var(--header-bg), black 25%) 100%);
  color: var(--header-text);
}

.post-header .site-title,
.post-header .post-title {
  color: var(--header-heading);
}

.post-header .site-nav a {
  color: var(--header-text);
  transition: color 0.3s ease;
}

/* Title + page links sit in the same 650px column as the home page */
.post-header-top {
  max-width: 650px;
  margin: 0 auto 60px;
}

.post-header-top .site-title {
  margin-top: 0;
}

.post-title {
  text-align: center;
  font-size: 44px;
  font-weight: 500;
  letter-spacing: -1.2px;
  line-height: 1.15;
  margin: 0 auto 50px;
  max-width: 650px;
  text-wrap: balance;
}

.post-meta {
  max-width: 650px;
  margin: 0 auto;
  padding: 1rem 0.5rem 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem 2rem;
}

.post-meta h5 {
  color: var(--header-label);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.7px;
  margin: 0 0 0.2rem;
}

.post-share {
  margin-left: auto;
}

.post-share-items {
  display: flex;
  gap: 1rem;
  position: relative;
}

.post-share-items a,
.post-share-items button {
  white-space: nowrap;
}

.post-share-items a {
  color: inherit;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  transition: color 0.3s ease;
}

.post-share-items .copy-link-btn,
.post-share-items .citation-popup-trigger {
  background: none;
  border: none;
  padding: 0;
  font: inherit;
  color: inherit;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  transition: color 0.3s ease;
}

.post-header + main {
  margin-top: 2.5rem;
}

/* Citation popup */
.citation-popup {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  z-index: 1000;
  justify-content: center;
  align-items: center;
}

.citation-popup.active {
  display: flex;
}

.citation-popup-content {
  background: var(--popup-bg);
  border-radius: 8px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
  max-width: 600px;
  width: 90%;
  max-height: 90vh;
  overflow: auto;
  white-space: normal;
  color: var(--text); /* reset: popup sits inside the header band */
}

.citation-popup-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--rule);
  font-weight: 600;
  color: var(--popup-heading);
}

.citation-popup-close {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text);
  line-height: 1;
  padding: 0;
}

.citation-popup-close:hover {
  color: var(--popup-heading);
}

.citation-popup-body {
  padding: 1.25rem;
}

.citation-popup-body pre {
  background: var(--code-bg);
  border-radius: 4px;
  padding: 1rem;
  overflow-x: auto;
  margin: 0 0 1rem;
  font-size: 0.875rem;
  line-height: 1.5;
  min-height: 1.5em;
}

.citation-popup-body code {
  font-family: "Fira Code", Monaco, Consolas, monospace;
  white-space: pre;
}

.citation-copy-btn {
  background: var(--button);
  color: #fff;
  border: none;
  border-radius: 4px;
  padding: 0.5rem 1rem;
  cursor: pointer;
  font: inherit;
  font-size: 0.875rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: background 0.2s ease;
}

.citation-copy-btn:hover {
  background: color-mix(in srgb, var(--button), black 15%);
}

.citation-copy-btn.copied {
  background: #198754;
}

@media (max-width: 520px) {
  .post-title {
    font-size: 34px;
  }
  .post-share {
    margin-left: 0;
  }
}