/* Weight-space programming lab: Blink's light paper theme. One cobalt accent, one lime flash, Geist type.
   Light only: a dark system setting draws the same page. */

@font-face{font-family:"Geist";font-style:normal;font-weight:100 900;font-display:swap;src:url(fonts/geist-latin-ext-wght-normal.woff2) format("woff2");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF}
@font-face{font-family:"Geist";font-style:normal;font-weight:100 900;font-display:swap;src:url(fonts/geist-latin-wght-normal.woff2) format("woff2");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}
@font-face{font-family:"Geist";font-style:italic;font-weight:100 900;font-display:swap;src:url(fonts/geist-latin-ext-wght-italic.woff2) format("woff2");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF}
@font-face{font-family:"Geist";font-style:italic;font-weight:100 900;font-display:swap;src:url(fonts/geist-latin-wght-italic.woff2) format("woff2");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}
@font-face{font-family:"Geist Mono";font-style:normal;font-weight:100 900;font-display:swap;src:url(fonts/geist-mono-latin-ext-wght-normal.woff2) format("woff2");unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF}
@font-face{font-family:"Geist Mono";font-style:normal;font-weight:100 900;font-display:swap;src:url(fonts/geist-mono-latin-wght-normal.woff2) format("woff2");unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}

:root {
  --color-canvas: #f5f5f5;
  --color-paper: #ffffff;
  --color-surface-alt: #fafafa;
  --color-ink: #0a0a0a;
  --color-ink-soft: #171717;
  --color-mid-gray: #737373;
  --color-mid-gray-canvas: #666666;
  --color-hairline: #e5e5e5;
  --color-accent: #2447f5;
  --color-accent-hover: #1c38d0;
  --color-accent-tint: #eef1fe;
  --color-flash: #d4f55c;
  --color-flash-ink: #0a0a0a;

  --canvas: var(--color-canvas);
  --paper: var(--color-paper);
  --alt: var(--color-surface-alt);
  --ink: var(--color-ink);
  --ink-soft: var(--color-ink-soft);
  --mid: var(--color-mid-gray);
  --mid-c: var(--color-mid-gray-canvas);
  --line: var(--color-hairline);
  --line-strong: #d4d4d4;
  --accent: var(--color-accent);
  --accent-ink: var(--color-accent-hover);
  --accent-tint: var(--color-accent-tint);
  --flash: var(--color-flash);

  --font-geist: Geist, Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-geist-mono: "Geist Mono", ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  --text-caption: 12px;
  --text-body: 14px;
  --text-heading-sm: 24px;

  --radius-cards: 24px;
  --radius-pill: 18px;
  --radius-nested: 10px;
  --radius-small: 6px;
  --shadow-subtle: 0 0 0 1px rgba(23, 23, 23, 0.05), 0 1px 3px rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
  --ring: 0 0 0 2px var(--color-paper), 0 0 0 4px var(--color-accent);
  --ease: cubic-bezier(0.22, 0.8, 0.3, 1);

  --gutter: clamp(16px, 4vw, 32px);
  --top-h: 56px;
  color-scheme: only light;
}

/* --- shell --------------------------------------------------------------------------- */

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

html {
  background: var(--canvas);
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-padding-top: calc(var(--top-h) + 16px);
}

body {
  margin: 0;
  /* a column, so a short page still puts the footer at the bottom of the window */
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
  background: var(--canvas);
  color: var(--ink);
  font-family: var(--font-geist);
  font-size: var(--text-body);
  line-height: 1.5;
  font-feature-settings: "ss01" on, "cv11" on;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

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

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

::selection {
  background: var(--accent-tint);
}

.skip {
  position: absolute;
  left: 12px;
  top: -48px;
  z-index: 20;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  background: var(--paper);
  border: 1px solid var(--line);
  color: var(--ink);
  font-weight: 500;
  text-decoration: none;
}

.skip:focus {
  top: 10px;
}

/* --- top bar: frosted over the canvas ----------------------------------------------- */

.top {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(245, 245, 245, 0.82);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}

.top-in {
  max-width: 1280px;
  height: var(--top-h);
  margin: 0 auto;
  padding: 0 var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  color: var(--ink);
  text-decoration: none;
  font-weight: 600;
  font-size: 18px;
  letter-spacing: -0.03em;
  line-height: 1;
  white-space: nowrap;
}

.brand:hover {
  color: var(--ink);
}

.top-links {
  display: flex;
  align-items: center;
  gap: 2px;
}

.top-links a {
  height: 32px;
  display: inline-flex;
  align-items: center;
  padding: 0 12px;
  border-radius: var(--radius-pill);
  color: var(--mid-c);
  font-weight: 500;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 0.15s ease, color 0.15s ease;
}

.top-links a:hover {
  background: rgba(10, 10, 10, 0.05);
  color: var(--ink);
}

/* where you are: the page (or, on a lab, the labs) on paper */
.top-links a[aria-current] {
  background: var(--paper);
  color: var(--ink);
  box-shadow: inset 0 0 0 1px var(--line);
}

/* --- pages: one column on paper, the contents beside it ------------------------------- */

.page {
  max-width: 1120px;
  margin: 0 auto;
  padding: 32px var(--gutter) 24px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 208px;
  gap: 40px;
  align-items: start;
}

/* a page without contents (the results table) gets the width the contents would use; text keeps its measure */
.page.solo {
  grid-template-columns: minmax(0, 1fr);
}

.page.solo .prose > :is(p, ul, ol, blockquote) {
  max-width: 720px;
}

.doc {
  min-width: 0;
}

.prose {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-cards);
  box-shadow: var(--shadow-subtle);
  padding: 40px 48px 44px;
  min-width: 0;
  /* a bare URL as link text would otherwise push a phone screen sideways */
  overflow-wrap: break-word;
}

.toc {
  position: sticky;
  top: calc(var(--top-h) + 32px);
  max-height: calc(100vh - var(--top-h) - 64px);
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
}

.toc-title {
  margin: 4px 0 8px;
  font-size: var(--text-caption);
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--mid-c);
}

.toc ul,
.tocm ul {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 1px solid var(--line);
}

.toc li a,
.tocm li a {
  display: block;
  margin-left: -1px;
  padding: 4px 0 4px 12px;
  border-left: 2px solid transparent;
  color: var(--mid-c);
  font-size: 13px;
  line-height: 1.4;
  text-decoration: none;
}

.toc li.l3 a,
.tocm li.l3 a {
  padding-left: 24px;
  font-size: 12.5px;
}

.toc li a:hover,
.tocm li a:hover {
  color: var(--ink);
}

.toc li a[aria-current="location"] {
  color: var(--ink);
  border-left-color: var(--accent);
}

.toc code,
.tocm code {
  font-family: var(--font-geist-mono);
  font-size: 0.92em;
}

.toc .katex,
.tocm .katex {
  font-size: 1em;
}

.tocm {
  display: none;
}

.tocm > summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 0;
  font-size: 13px;
  font-weight: 500;
  color: var(--ink-soft);
}

.tocm > summary::-webkit-details-marker {
  display: none;
}

.tocm nav {
  padding: 4px 0 12px;
}

/* a lab's neighbours, under the page */
.pager {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 16px;
  margin: 16px 0 0;
}

.pager a {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 14px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: var(--paper);
  box-shadow: var(--shadow-subtle);
  color: var(--ink);
  text-decoration: none;
  transition: border-color 0.15s ease;
}

.pager a:hover {
  border-color: var(--line-strong);
  color: var(--ink);
}

.pager span {
  font-size: var(--text-caption);
  font-weight: 500;
  color: var(--mid-c);
}

.pager b {
  font-size: 14px;
  font-weight: 600;
  line-height: 1.4;
}

.pager .next {
  grid-column: 2;
  text-align: right;
}

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

.prose > :first-child {
  margin-top: 0;
}

.prose h1 {
  margin: 0 0 16px;
  font-size: 36px;
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.04em;
  color: var(--ink);
}

/* a second part of a long page starts with its own title */
.prose * + h1 {
  margin-top: 56px;
  padding-top: 32px;
  border-top: 1px solid var(--line);
  font-size: 30px;
}

.prose h2 {
  margin: 44px 0 12px;
  font-size: var(--text-heading-sm);
  font-weight: 600;
  line-height: 1.33;
  letter-spacing: -0.025em;
  color: var(--ink);
}

.prose h3 {
  margin: 32px 0 8px;
  font-size: 18px;
  font-weight: 600;
  line-height: 1.4;
  letter-spacing: -0.015em;
  color: var(--ink);
}

.prose h4 {
  margin: 24px 0 6px;
  font-size: 15px;
  font-weight: 600;
}

.prose :is(h1, h2, h3, h4) .anchor {
  margin-left: 8px;
  color: var(--line-strong);
  font-weight: 500;
  text-decoration: none;
  opacity: 0;
  transition: opacity 0.15s ease;
}

.prose :is(h1, h2, h3, h4):hover .anchor,
.prose :is(h1, h2, h3, h4) .anchor:focus-visible {
  opacity: 1;
}

.prose :is(h1, h2, h3, h4) .anchor:hover {
  color: var(--accent);
}

.prose p,
.prose li {
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.prose p {
  margin: 0 0 14px;
}

.prose :is(ul, ol) {
  margin: 0 0 14px;
  padding-left: 22px;
}

.prose li {
  margin: 4px 0;
}

.prose li > :is(ul, ol) {
  margin: 4px 0 0;
}

.prose li > p {
  margin: 0 0 6px;
}

.prose li::marker {
  color: var(--mid);
}

.prose strong {
  font-weight: 600;
  color: var(--ink);
}

.prose hr {
  border: 0;
  height: 1px;
  background: var(--line);
  margin: 32px 0;
}

.prose blockquote {
  margin: 0 0 14px;
  padding: 2px 0 2px 16px;
  border-left: 2px solid var(--line-strong);
}

.prose blockquote p {
  color: var(--mid-c);
}

.prose :not(pre) > code {
  font-family: var(--font-geist-mono);
  font-size: 0.86em;
  padding: 1px 6px;
  border-radius: var(--radius-small);
  background: var(--canvas);
  color: var(--ink);
  overflow-wrap: anywhere;
}

.prose img {
  display: block;
  max-width: 100%;
  height: auto;
  margin: 8px 0 20px;
  border-radius: var(--radius-nested);
  border: 1px solid var(--line);
}

/* math: KaTeX, set a little smaller than its default so it sits with Geist */
.prose .katex {
  font-size: 1.1em;
}

.math-display {
  display: block;
  margin: 0 0 14px;
  overflow-x: auto;
  overflow-y: hidden;
  scrollbar-width: thin;
}

.math-display .katex-display {
  margin: 0;
  padding: 6px 0;
}

/* diagrams: drawn by Mermaid when the site was built, on a hairline card; a wide one scrolls rather than
   shrink its labels past reading */
.prose .mermaid-svg {
  margin: 4px 0 20px;
  padding: 16px;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: var(--paper);
  scrollbar-width: thin;
}

.prose .mermaid-svg svg {
  display: block;
  margin: 0 auto;
  width: 100%;
  height: auto;
  min-width: var(--mw, 0);
}

.prose .mermaid-svg p {
  margin: 0;
  font-size: inherit;
  line-height: inherit;
  color: inherit;
}

/* code: a hairline card with its language named and, with scripts on, a copy pill */
.code {
  margin: 0 0 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: var(--alt);
  overflow: hidden;
}

.code-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 36px;
  padding: 4px 6px 4px 16px;
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}

.code-lang {
  font-family: var(--font-geist-mono);
  font-size: 11.5px;
  color: var(--mid);
}

.copy {
  height: 26px;
  padding: 0 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: var(--paper);
  color: var(--ink-soft);
  font-family: var(--font-geist);
  font-size: 12px;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.15s ease, border-color 0.15s ease;
}

.copy:hover {
  background: var(--alt);
  border-color: var(--line-strong);
}

.copy.done {
  background: var(--flash);
  border-color: transparent;
  color: var(--color-flash-ink);
}

.code pre {
  margin: 0;
  padding: 14px 16px;
  overflow-x: auto;
  font-family: var(--font-geist-mono);
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--ink-soft);
  tab-size: 4;
}

.code code {
  font-family: inherit;
}

/* code in a list sits with the item's text */
.prose li > .code {
  margin: 8px 0 10px;
}

/* tables: a hairline card that scrolls sideways when the table is wider than the page */
.table-wrap {
  margin: 0 0 18px;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: var(--paper);
  scrollbar-width: thin;
}

/* a box that scrolls sideways shows a soft shadow on the side with more to see */
.table-wrap,
.prose .mermaid-svg {
  background:
    linear-gradient(90deg, var(--paper) 30%, rgba(255, 255, 255, 0)) 0 0 / 40px 100% no-repeat local,
    linear-gradient(270deg, var(--paper) 30%, rgba(255, 255, 255, 0)) 100% 0 / 40px 100% no-repeat local,
    radial-gradient(farthest-side at 0 50%, rgba(0, 0, 0, 0.13), rgba(0, 0, 0, 0)) 0 0 / 12px 100% no-repeat,
    radial-gradient(farthest-side at 100% 50%, rgba(0, 0, 0, 0.13), rgba(0, 0, 0, 0)) 100% 0 / 12px 100% no-repeat,
    var(--paper);
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  font-variant-numeric: tabular-nums;
}

.prose th,
.prose td {
  padding: 8px 14px;
  border: 0;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
  line-height: 1.5;
}

.prose th {
  font-size: var(--text-caption);
  font-weight: 500;
  color: var(--mid);
  background: var(--alt);
  /* headers wrap, as on GitHub: long ones ("cut answers ending in repetition %") would set the table's width */
}

.prose td {
  color: var(--ink-soft);
}

/* code in a cell wraps only at a space or before a '/' (build.py marks those); a token never splits, and the table
   scrolls sideways instead */
.prose code.cell {
  overflow-wrap: normal;
  word-break: normal;
  -webkit-box-decoration-break: clone;
  box-decoration-break: clone;
}

.prose code.cell > span {
  white-space: nowrap;
}

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

/* progressive disclosure: a thin chevron that turns */
.prose details {
  margin: 0 0 14px;
  border-bottom: 1px solid var(--line);
}

.prose details > summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 0;
  font-size: var(--text-body);
  font-weight: 500;
  color: var(--ink-soft);
  transition: color 0.15s ease;
}

.prose details > summary::-webkit-details-marker {
  display: none;
}

.prose details > summary::before,
.tocm > summary::before {
  content: "";
  width: 6px;
  height: 6px;
  flex: none;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(-45deg);
  transition: transform 0.2s var(--ease);
}

.prose details[open] > summary::before,
.tocm[open] > summary::before {
  transform: rotate(45deg);
}

.prose details > summary:hover {
  color: var(--ink);
}

.prose details[open] > summary {
  margin-bottom: 4px;
}

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

body > .top + * {
  width: 100%;
  margin-bottom: 48px;
}

.foot {
  border-top: 1px solid var(--line);
  margin-top: auto;
}

.foot-in {
  max-width: 1280px;
  margin: 0 auto;
  padding: 20px var(--gutter) 40px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px 32px;
}

.foot-note {
  margin: 0;
  max-width: 72ch;
  font-size: var(--text-caption);
  line-height: 1.6;
  color: var(--mid-c);
}

.foot-note a {
  color: var(--mid-c);
}

.foot-note a:hover {
  color: var(--ink);
}

.foot-links {
  margin: 0;
  display: flex;
  gap: 16px;
  font-size: var(--text-caption);
  line-height: 1.6;
}

.foot-links a {
  color: var(--mid-c);
}

.foot-links a:hover {
  color: var(--ink);
}

/* --- narrower screens ---------------------------------------------------------------------- */

@media (max-width: 1080px) {
  .page {
    grid-template-columns: minmax(0, 1fr);
    max-width: 884px;
  }

  .toc {
    display: none;
  }

  .tocm {
    display: block;
    margin: 0 0 24px;
    padding: 4px 16px;
    border: 1px solid var(--line);
    border-radius: var(--radius-pill);
    background: var(--alt);
  }
}

@media (max-width: 860px) {
  .prose {
    padding: 28px 24px 32px;
  }
}

/* the name above, the links in a row below it that scrolls sideways when it must */
@media (max-width: 760px) {
  :root {
    --top-h: 88px;
  }

  .top-in {
    height: auto;
    padding-top: 10px;
    padding-bottom: 6px;
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
  }

  .brand {
    font-size: 17px;
  }

  .top-links {
    margin: 0 calc(-1 * var(--gutter));
    padding: 0 var(--gutter);
    overflow-x: auto;
    scrollbar-width: none;
  }

  .top-links::-webkit-scrollbar {
    display: none;
  }
}

@media (max-width: 720px) {
  .top-links a {
    padding: 0 9px;
  }

  .page {
    padding-top: 16px;
  }

  .prose {
    padding: 22px 18px 26px;
    border-radius: 20px;
  }

  .prose h1 {
    font-size: 30px;
  }

  .prose * + h1 {
    font-size: 26px;
  }

  .prose h2 {
    font-size: 21px;
    margin-top: 36px;
  }

  .prose h3 {
    font-size: 17px;
  }

  .prose p,
  .prose li {
    font-size: 15px;
    line-height: 1.65;
  }

  .prose th,
  .prose td {
    padding: 7px 10px;
  }

  .prose .mermaid-svg {
    padding: 12px;
  }

  .pager {
    grid-template-columns: minmax(0, 1fr);
  }

  .pager .next {
    grid-column: auto;
  }

  .foot-links {
    flex-wrap: wrap;
  }
}

/* a phone: all six links in one row (narrower screens scroll it sideways) */
@media (max-width: 430px) {
  .top-links {
    justify-content: space-between;
  }

  .top-links a {
    padding: 0 6px;
    font-size: 13px;
  }
}

/* everything lands in its final state at once */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-delay: 0ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}