/* opty — hand-crafted minimal, Hundred Rabbits-flavored */

:root {
  /* light — parchment */
  --bg: #f1ede4;
  --bg-shade: #e8e2d3;
  --ink: #181717;
  --ink-soft: #5a5a58;
  --rule: #c8c1b0;
  --dither-opacity: 0.12;
  --grain-opacity: 0.55;
  --pre-bg: #e8e2d3;

  --serif: "Iowan Old Style", "Sitka Text", "Palatino", "Book Antiqua", "Georgia", serif;
  --sans: "Inter", "Helvetica Neue", "Helvetica", "Arial", sans-serif;
  --mono: "JetBrains Mono", "SF Mono", "Menlo", "Consolas", monospace;

  --measure: 640px;
  --unit: 5px;
}

[data-theme="dark"] {
  /* dark — midnight logbook */
  --bg: #17160f;
  --bg-shade: #1f1e17;
  --ink: #e8e2d3;
  --ink-soft: #8e8676;
  --rule: #3a382f;
  --dither-opacity: 0.18;
  --grain-opacity: 0.35;
  --pre-bg: #1f1e17;
}

/* reset */
*,*::before,*::after { box-sizing: border-box; }
html { text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--serif);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.55;
  font-size: 16px;
  transition: background 0.25s ease, color 0.25s ease;
}

/* dithered background — SVG Bayer pattern */
.dither {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  color: var(--ink);
  opacity: var(--dither-opacity);
  mix-blend-mode: multiply;
}
[data-theme="dark"] .dither {
  mix-blend-mode: screen;
}

/* paper grain overlay */
.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: var(--grain-opacity);
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='140' height='140' viewBox='0 0 140 140'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 0.09  0 0 0 0 0.09  0 0 0 0 0.09  0 0 0 0.06 0'/></filter><rect width='140' height='140' filter='url(%23n)'/></svg>");
}
[data-theme="dark"] .grain {
  mix-blend-mode: screen;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='140' height='140' viewBox='0 0 140 140'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 0.92  0 0 0 0 0.89  0 0 0 0 0.83  0 0 0 0.05 0'/></filter><rect width='140' height='140' filter='url(%23n)'/></svg>");
}

main {
  position: relative;
  z-index: 2;
  max-width: var(--measure);
  margin: 0 auto;
  padding: calc(var(--unit) * 10) calc(var(--unit) * 4) calc(var(--unit) * 16);
}

/* theme toggle */
.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 10;
  width: 36px;
  height: 36px;
  padding: 7px;
  background: transparent;
  border: 1px solid var(--ink);
  color: var(--ink);
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
  border-radius: 0;
}
.theme-toggle:hover {
  background: var(--ink);
  color: var(--bg);
}
.theme-toggle svg {
  width: 100%;
  height: 100%;
  display: block;
}
.theme-toggle .icon-moon { display: none; }
[data-theme="dark"] .theme-toggle .icon-sun { display: none; }
[data-theme="dark"] .theme-toggle .icon-moon { display: block; }

/* header */
header {
  text-align: center;
  margin-bottom: calc(var(--unit) * 8);
}
.crest {
  width: 72px;
  height: 72px;
  color: var(--ink);
  display: block;
  margin: 0 auto calc(var(--unit) * 3);
}
h1 {
  font-family: var(--serif);
  font-size: 44px;
  font-weight: 400;
  letter-spacing: -0.01em;
  margin: 0 0 calc(var(--unit) * 2);
  font-variant: small-caps;
}
.tagline {
  margin: 0;
  font-size: 15px;
  color: var(--ink-soft);
  font-style: italic;
  letter-spacing: 0.01em;
}

/* section icons — hand-drawn 1-bit */
.sec-icon {
  width: 22px;
  height: 22px;
  display: inline-block;
  vertical-align: middle;
  margin-right: 8px;
  color: var(--ink);
  opacity: 0.82;
  flex-shrink: 0;
}

/* headings */
h2 {
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 600;
  font-variant: small-caps;
  letter-spacing: 0.04em;
  margin: 0 0 calc(var(--unit) * 4);
  border-bottom: 1px solid var(--ink);
  padding-bottom: calc(var(--unit) * 1);
  display: flex;
  align-items: center;
}
h3 {
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 600;
  font-style: italic;
  margin: calc(var(--unit) * 6) 0 calc(var(--unit) * 3);
  color: var(--ink);
}

/* sections */
section {
  margin: calc(var(--unit) * 8) 0;
}

/* paragraphs */
p {
  margin: 0 0 calc(var(--unit) * 3);
}

/* quickstart block */
.quickstart {
  text-align: center;
  margin: calc(var(--unit) * 6) 0;
}
.quickstart pre {
  display: inline-block;
  margin: 0;
}

/* code blocks */
pre, code {
  font-family: var(--mono);
  font-size: 13px;
}
p > code, li > code, dd > code, td > code {
  background: var(--bg-shade);
  padding: 1px 5px;
  border: 1px solid var(--rule);
  font-size: 12.5px;
}
pre {
  background: var(--pre-bg);
  border: 1px solid var(--ink);
  padding: calc(var(--unit) * 3) calc(var(--unit) * 4);
  overflow-x: auto;
  line-height: 1.45;
  margin: calc(var(--unit) * 4) 0;
}
pre code {
  background: transparent;
  border: 0;
  padding: 0;
  font-size: 13px;
  color: var(--ink);
}
pre.report {
  font-size: 11.5px;
  line-height: 1.5;
}

/* logbook tables */
table.logbook {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--mono);
  font-size: 12.5px;
  margin: calc(var(--unit) * 4) 0;
}
table.logbook th,
table.logbook td {
  text-align: left;
  padding: calc(var(--unit) * 1.2) calc(var(--unit) * 2);
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  vertical-align: top;
}
table.logbook thead th {
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
  font-weight: 600;
  font-family: var(--serif);
  font-variant: small-caps;
  letter-spacing: 0.05em;
  font-size: 12px;
}
table.logbook tbody tr:last-child td {
  border-bottom: 2px solid var(--ink);
}
table.logbook td.num {
  text-align: right;
  width: 3em;
  color: var(--ink-soft);
}
table.logbook.small td,
table.logbook.small th {
  padding: calc(var(--unit) * 0.8) calc(var(--unit) * 2);
}

/* commands list */
dl.commands {
  margin: calc(var(--unit) * 4) 0;
  font-size: 15px;
}
dl.commands dt {
  margin-top: calc(var(--unit) * 3);
  font-family: var(--mono);
  font-size: 13px;
}
dl.commands dt code {
  background: transparent;
  border: 0;
  padding: 0;
  color: var(--ink);
  font-weight: 600;
}
dl.commands dd {
  margin: calc(var(--unit) * 1) 0 0 calc(var(--unit) * 4);
  color: var(--ink);
  font-style: italic;
}

/* plain lists */
ul.plain {
  list-style: none;
  padding-left: 0;
  margin: calc(var(--unit) * 3) 0;
}
ul.plain li {
  padding-left: calc(var(--unit) * 4);
  position: relative;
  margin-bottom: calc(var(--unit) * 1);
}
ul.plain li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--ink-soft);
}

/* dividers */
hr.divider-dots,
hr.divider-rule {
  border: 0;
  margin: calc(var(--unit) * 8) 0;
  text-align: center;
}
hr.divider-dots {
  height: 3px;
  background-image: radial-gradient(circle, var(--ink) 1px, transparent 1.2px);
  background-size: 16px 3px;
  background-repeat: repeat-x;
  background-position: center;
  opacity: 0.65;
}
hr.divider-rule {
  height: 1px;
  background: var(--ink);
  opacity: 0.35;
}

/* links */
a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}
a:hover {
  background: var(--ink);
  color: var(--bg);
  text-decoration: none;
}

/* footer */
footer {
  margin-top: calc(var(--unit) * 16);
  text-align: center;
  font-size: 13px;
  color: var(--ink-soft);
  font-family: var(--sans);
}
footer p { margin: calc(var(--unit) * 2) 0; }
footer .faint { font-style: italic; color: var(--ink-soft); opacity: 0.75; }
footer a { display: inline-block; padding: 6px 4px; }

/* responsive */
@media (max-width: 640px) {
  main { padding: calc(var(--unit) * 6) calc(var(--unit) * 3) calc(var(--unit) * 10); }
  h1 { font-size: 34px; }
  h2 { font-size: 19px; }
  .sec-icon { width: 18px; height: 18px; margin-right: 6px; }
  table.logbook { font-size: 12.5px; }
  dl.commands dd { margin-left: calc(var(--unit) * 2); }
  pre { font-size: 12px; padding: calc(var(--unit) * 2) calc(var(--unit) * 2.5); }
  .theme-toggle { top: 12px; right: 12px; width: 32px; height: 32px; padding: 6px; }
}

/* print — actually usable on paper */
@media print {
  .grain, .dither, .theme-toggle { display: none !important; }
  body { background: white; color: black; }
  main { max-width: 100%; padding: 0; }
  a { color: black; text-decoration: underline; }
}

/* reduced motion */
@media (prefers-reduced-motion: reduce) {
  body, .theme-toggle { transition: none !important; }
}