/* ============================================================================
   b012_data — engineering journal / warm-dark editorial
   ============================================================================ */

:root {
  /* ---- palette ---- */
  --bg:           #0E0D0B;
  --bg-2:         #141210;
  --ink:          #E8DFC9;          /* primary text on dark */
  --ink-dim:      #A79B82;
  --ink-faint:    #6B6350;
  --paper:        #F4EBD8;
  --paper-ink:    #1B1814;
  --rule:         #26221D;
  --rule-2:       #332D25;

  --accent:       #FF7A1A;          /* signature amber */
  --accent-soft:  #FFB454;
  --accent-deep:  #D15A0A;
  --accent-green: #93B36B;
  --accent-green-deep: #6F8D4F;
  --secondary:    #8AB7B5;          /* distant teal for variety */

  --code-bg:      #0A0907;

  --chevron: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='10' height='6' viewBox='0 0 10 6' fill='none'><path d='M1 1l4 4 4-4' stroke='%23E8DFC9' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/></svg>");

  /* ---- type ---- */
  --serif:   'Newsreader', 'Iowan Old Style', Georgia, serif;
  --display: 'Instrument Serif', 'Newsreader', Georgia, serif;
  --sans:    'Manrope', ui-sans-serif, -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  --mono:    'JetBrains Mono', ui-monospace, 'SFMono-Regular', Menlo, Monaco, Consolas, monospace;

  /* ---- metrics ---- */
  --r-sm: 4px;
  --r:    8px;
  --r-lg: 14px;
  --maxw: 1280px;
  --gutter: clamp(20px, 4vw, 56px);

  --ease: cubic-bezier(.22, .61, .36, 1);
}

:root[data-theme="light"] {
  --bg:           #F5F0E6;
  --bg-2:         #ECE4D6;
  --ink:          #241F17;
  --ink-dim:      #5F5444;
  --ink-faint:    #8C7F6C;
  --paper:        #FFF9EF;
  --paper-ink:    #1C1711;
  --rule:         #D7CBB8;
  --rule-2:       #C7B89F;
  --accent:       #B7601D;
  --accent-soft:  #D98A42;
  --accent-deep:  #8C4513;
  --accent-green: #6E9151;
  --accent-green-deep: #55703D;
  --secondary:    #4E7F7B;
  --code-bg:      #EBE4D5;
  --chevron: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='10' height='6' viewBox='0 0 10 6' fill='none'><path d='M1 1l4 4 4-4' stroke='%23241F17' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/></svg>");
}

:root[data-theme="nature"] {
  --bg:           #0E1711;
  --bg-2:         #132018;
  --ink:          #E2ECD8;
  --ink-dim:      #A8B89A;
  --ink-faint:    #71816D;
  --paper:        #E8F0E0;
  --paper-ink:    #132016;
  --rule:         #233127;
  --rule-2:       #314438;
  --accent:       #8DBE67;
  --accent-soft:  #B2D88A;
  --accent-deep:  #689249;
  --accent-green: #BEE08B;
  --accent-green-deep: #88AE5E;
  --secondary:    #79B6A1;
  --code-bg:      #080D0A;
  --chevron: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='10' height='6' viewBox='0 0 10 6' fill='none'><path d='M1 1l4 4 4-4' stroke='%23E2ECD8' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/></svg>");
}

/* ---------- reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 88px; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.7;
  font-weight: 380;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
img, svg { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; text-underline-offset: 3px; }
a:hover { text-decoration: underline; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
ul, ol { margin: 0; padding: 0; }
h1, h2, h3, h4, h5 { margin: 0; font-weight: 500; letter-spacing: -0.01em; }
p { margin: 0 0 1em; }
code, pre { font-family: var(--mono); font-size: 0.88em; }
code { color: var(--accent-soft); }
pre code { color: var(--ink); }

.skip-link {
  position: absolute; left: -999em; top: 0;
  background: var(--accent); color: #000; padding: 10px 14px; font-family: var(--sans); font-weight: 600;
}
.skip-link:focus { left: 8px; top: 8px; z-index: 100; }

/* ---------- grain ---------- */
.grain {
  position: fixed; inset: 0; pointer-events: none; z-index: 2;
  opacity: .05; mix-blend-mode: overlay;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 1  0 0 0 0 0.92  0 0 0 0 0.8  0 0 0 0.6 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' /%3E%3C/svg%3E");
}

/* ---------- topbar ---------- */
.topbar {
  position: sticky; top: 0; z-index: 20;
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  border-bottom: 1px solid var(--rule);
}
.topbar__inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 14px var(--gutter);
  display: grid;
  grid-template-columns: auto 1fr auto auto;
  gap: 32px;
  align-items: center;
}
.brand {
  font-family: var(--mono);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.02em;
  color: var(--ink);
  display: inline-flex; align-items: center; gap: 2px;
  text-decoration: none;
}
.brand:hover { text-decoration: none; }
.brand__bracket { color: var(--accent); font-weight: 400; }
.brand__slash   { color: var(--accent); }

.nav {
  display: flex; gap: 28px; justify-self: center;
  font-family: var(--sans);
  font-size: 13px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.nav a {
  color: var(--ink-dim);
  font-weight: 500;
  position: relative;
  padding: 6px 2px;
  transition: color .2s var(--ease);
}
.nav a:hover { color: var(--ink); text-decoration: none; }
.nav a::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -2px; height: 1px;
  background: var(--accent); transform: scaleX(0); transform-origin: left;
  transition: transform .3s var(--ease);
}
.nav a:hover::after { transform: scaleX(1); }

.topbar__actions { display: flex; gap: 10px; align-items: center; }

.topbar__prefs {
  display: flex;
  gap: 8px;
  align-items: center;
}

.topbar__select {
  appearance: none;
  -webkit-appearance: none;
  background-color: transparent;
  background-image: var(--chevron);
  background-repeat: no-repeat;
  background-position: right 8px center;
  border: 1px solid transparent;
  border-radius: var(--r-sm);
  color: var(--ink-dim);
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1.7;
  padding: 10px 26px 10px 10px;
  cursor: pointer;
  transition: color .2s var(--ease), background-color .2s var(--ease);
  outline: none;
}

.topbar__select:hover {
  color: var(--ink);
  background-color: color-mix(in srgb, var(--ink) 5%, transparent);
}

.topbar__select:focus-visible {
  color: var(--ink);
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent);
}

.topbar__select option {
  background: var(--bg-2);
  color: var(--ink);
}
.nav-toggle {
  display: none;
  width: 36px; height: 32px; padding: 0;
  flex-direction: column; justify-content: center; gap: 5px;
}
.nav-toggle span {
  display: block; height: 1.5px; background: var(--ink);
  transition: transform .3s var(--ease), opacity .3s var(--ease);
}
.nav-toggle span:nth-child(1) { width: 22px; margin-left: auto; }
.nav-toggle span:nth-child(2) { width: 16px; margin-left: auto; }
.nav-toggle span:nth-child(3) { width: 22px; margin-left: auto; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 6px;
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
  padding: 10px 16px;
  border-radius: var(--r-sm);
  border: 1px solid transparent;
  transition: all .2s var(--ease);
  white-space: nowrap;
  text-decoration: none !important;
}
.btn--solid {
  background: var(--ink); color: var(--bg);
}
.btn--solid:hover { background: #fff; }

.btn--ghost {
  color: var(--ink);
  border-color: var(--rule-2);
  background: transparent;
}
.btn--ghost:hover { border-color: var(--ink-dim); background: rgba(255,255,255,.02); }

.btn--primary {
  background: var(--accent); color: #110E0A;
  box-shadow: 0 1px 0 #ffffff22 inset, 0 10px 30px -10px var(--accent);
  padding: 14px 22px;
  font-size: 14px;
}
.btn--primary:hover { background: var(--accent-soft); transform: translateY(-1px); }

/* ---------- hero ---------- */
.hero {
  position: relative;
  padding: clamp(48px, 8vw, 100px) var(--gutter) 0;
  max-width: var(--maxw);
  margin: 0 auto;
  overflow: hidden;
}
.hero__bg {
  position: absolute; inset: 0; pointer-events: none; z-index: 0;
}
.hero__grid {
  position: absolute; inset: -10% -10% 0 -10%;
  background-image:
    linear-gradient(to right, #ffffff08 1px, transparent 1px),
    linear-gradient(to bottom, #ffffff08 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse at 60% 20%, black 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at 60% 20%, black 0%, transparent 70%);
}
.hero__bg::before {
  content: "";
  position: absolute; top: -200px; right: -200px; width: 900px; height: 900px;
  background: radial-gradient(circle, rgba(255,122,26,0.18), transparent 60%);
  filter: blur(40px);
}
.hero__inner {
  position: relative; z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: clamp(32px, 5vw, 72px);
  align-items: start;
}

/* eyebrow */
.eyebrow {
  display: inline-flex;
  gap: 10px; align-items: center;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-dim);
  margin-bottom: 28px;
}
.eyebrow .dot {
  width: 6px; height: 6px; border-radius: 50%; background: var(--accent);
  box-shadow: 0 0 12px var(--accent);
  animation: pulse 2.4s ease-in-out infinite;
}
.eyebrow__sep { color: var(--ink-faint); }
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: .55; transform: scale(.85); }
}

/* hero title */
.hero__title {
  font-family: var(--display);
  font-weight: 400;
  font-size: clamp(44px, 7vw, 96px);
  line-height: 0.98;
  letter-spacing: -0.025em;
  color: var(--ink);
  margin-bottom: 28px;
  text-wrap: balance;
}
.hero__package {
  color: var(--accent-green);
  font-weight: 800;
  text-shadow: 0 0 18px rgba(147, 179, 107, 0.12);
}
.hero__title em {
  font-family: var(--display);
  font-style: italic;
  color: var(--accent);
  display: inline-block;
}

.hero__lede {
  font-family: var(--serif);
  font-size: clamp(17px, 1.2vw, 19px);
  line-height: 1.65;
  color: var(--ink);
  max-width: 58ch;
  margin-bottom: 36px;
}
.hero__lede strong {
  font-weight: 600;
  color: var(--accent-green);
  font-family: var(--sans);
  background: linear-gradient(90deg, transparent, rgba(147, 179, 107, 0.14), transparent);
  padding: 2px 6px;
}

.install {
  border: 1px solid var(--rule-2);
  border-radius: var(--r);
  background: var(--code-bg);
  padding: 14px 18px 16px;
  margin-bottom: 28px;
  max-width: 520px;
}
.install__label {
  display: flex; gap: 10px; align-items: center;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-faint);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 8px;
}
.install__hash { color: var(--accent); font-weight: 700; }
.install__label code { color: var(--ink-dim); font-size: 12px; background: #0000; text-transform: none; letter-spacing: 0; }
.install__cmd {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
}
.install__cmd code {
  font-size: 15px;
  font-weight: 500;
}
.tok-key   { color: var(--ink); }
.tok-punct { color: var(--ink-faint); }
.tok-ver   { color: var(--accent); }

.copy-btn {
  font-family: var(--sans);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-dim);
  padding: 6px 10px;
  border: 1px solid var(--rule-2);
  border-radius: var(--r-sm);
  transition: all .2s var(--ease);
}
.copy-btn:hover { color: var(--ink); border-color: var(--accent); }
.copy-btn.is-copied { color: var(--bg); background: var(--accent); border-color: var(--accent); }

.hero__cta { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 44px; }

.hero__meta {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  list-style: none;
  border-top: 1px solid var(--rule);
  padding-top: 22px;
  max-width: 620px;
}
.hero__meta li {
  display: flex; flex-direction: column; gap: 8px;
  padding-right: 20px;
  font-family: var(--sans);
  font-size: 13px;
  color: var(--ink-dim);
  border-right: 1px solid var(--rule);
}
.hero__meta li:last-child { border-right: 0; }
.hero__meta .num {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.15em;
}

/* hero right -- code panel */
.hero__right { position: relative; z-index: 1; }
.panel {
  border: 1px solid var(--rule-2);
  border-radius: var(--r-lg);
  background: var(--code-bg);
  box-shadow:
    0 1px 0 rgba(255,255,255,0.04) inset,
    0 40px 80px -40px rgba(0,0,0,0.8),
    0 0 0 1px rgba(255,122,26,0.04);
  overflow: hidden;
  transform: perspective(1800px) rotateY(-3deg) rotateX(1deg);
  transition: transform .6s var(--ease);
}
.panel:hover { transform: perspective(1800px) rotateY(-1deg) rotateX(0deg); }

.panel__header {
  display: flex; align-items: center; gap: 14px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--rule);
  background: linear-gradient(180deg, #17130C, #100E09);
}
.panel__dots { display: inline-flex; gap: 7px; }
.panel__dots span {
  width: 10px; height: 10px; border-radius: 50%;
  background: var(--rule-2);
}
.panel__dots span:first-child { background: #3a2a16; }
.panel__file {
  font-family: var(--mono); font-size: 12px; color: var(--ink-dim);
  letter-spacing: 0.04em;
}
.panel__tag {
  margin-left: auto;
  font-family: var(--mono); font-size: 10px;
  color: var(--accent);
  border: 1px solid color-mix(in srgb, var(--accent) 50%, transparent);
  padding: 3px 8px; border-radius: 40px;
  text-transform: uppercase; letter-spacing: 0.15em;
}
.panel__code {
  margin: 0;
  padding: 20px 22px;
  font-family: var(--mono);
  font-size: 12.5px;
  line-height: 1.65;
  overflow-x: auto;
  color: var(--ink);
  background: transparent;
}
.panel__code .code-copy {
  opacity: 1;
}
.panel__footer {
  border-top: 1px dashed var(--rule-2);
  padding: 10px 18px;
  font-family: var(--serif);
  font-style: italic;
  font-size: 13px;
  color: var(--ink-dim);
}

/* marquee */
.marquee {
  margin-top: clamp(48px, 6vw, 80px);
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  padding: 16px 0;
  overflow: hidden;
  position: relative;
  mask-image: linear-gradient(90deg, transparent, black 10%, black 90%, transparent);
}
.marquee__track {
  display: inline-flex; align-items: center; gap: 42px;
  animation: marquee 38s linear infinite;
  white-space: nowrap;
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.3em;
  color: var(--ink-dim);
  text-transform: uppercase;
}
.marquee__track > span:not(.dot-sep) { padding-right: 0; }
.dot-sep {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--accent); display: inline-block; flex-shrink: 0;
}
@keyframes marquee {
  from { transform: translateX(0); }
  to   { transform: translateX(-50%); }
}

/* ---------- section primitives ---------- */
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(60px, 9vw, 120px) var(--gutter);
}
.section__head {
  max-width: 780px;
  margin-bottom: clamp(32px, 4vw, 56px);
}
.section__head--center {
  margin-left: auto; margin-right: auto;
  text-align: center;
}
.section__kicker {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--accent);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 16px;
}
.section__title {
  font-family: var(--display);
  font-weight: 400;
  font-size: clamp(32px, 4.4vw, 56px);
  line-height: 1.05;
  letter-spacing: -0.015em;
  color: var(--ink);
  margin-bottom: 18px;
  text-wrap: balance;
}
.section__sub {
  font-family: var(--serif);
  font-size: clamp(16px, 1.1vw, 18px);
  color: var(--ink-dim);
  max-width: 62ch;
  line-height: 1.65;
}
.section__head--center .section__sub { margin-left: auto; margin-right: auto; }

/* ---------- features ---------- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 0;
  border-top: 1px solid var(--rule);
  border-left: 1px solid var(--rule);
}
.feature {
  padding: 32px 28px;
  border-right: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  position: relative;
  transition: background .3s var(--ease);
}
.feature:hover { background: rgba(255,122,26,0.04); }
.feature::before {
  content: ""; position: absolute; top: 0; left: 0; width: 0; height: 2px;
  background: var(--accent); transition: width .4s var(--ease);
}
.feature:hover::before { width: 100%; }
.feature header { display: flex; gap: 12px; align-items: baseline; margin-bottom: 14px; }
.feature__num {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--accent);
  letter-spacing: 0.1em;
}
.feature h3 {
  font-family: var(--sans);
  font-size: 19px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--ink);
}
.feature p {
  font-family: var(--serif);
  font-size: 15.5px;
  color: var(--ink-dim);
  line-height: 1.6;
  margin-bottom: 16px;
}
.feature__meta {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--ink-faint);
}

/* ---------- rule divider ---------- */
.rule {
  position: relative;
  text-align: center;
  padding: 40px 0;
  max-width: var(--maxw);
  margin: 0 auto;
}
.rule::before {
  content: ""; position: absolute; top: 50%; left: var(--gutter); right: var(--gutter); height: 1px;
  background: var(--rule);
}
.rule span {
  position: relative;
  display: inline-block;
  background: var(--bg);
  padding: 0 20px;
  font-family: var(--display);
  font-style: italic;
  color: var(--accent);
  font-size: 22px;
}

/* ---------- layout w/ TOC ---------- */
.layout {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--gutter);
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: clamp(32px, 5vw, 72px);
  align-items: start;
}
.toc {
  position: sticky;
  top: 100px;
  font-family: var(--sans);
  font-size: 13.5px;
}
.toc__prefs {
  margin-bottom: 22px;
  padding: 16px;
  border: 1px solid var(--rule);
  border-radius: var(--r);
  background: color-mix(in srgb, var(--bg-2) 82%, transparent);
}
.toc__prefs-head {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 14px;
}
.prefs__field {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.prefs__field + .prefs__field {
  margin-top: 14px;
}
.prefs__label {
  color: var(--ink-dim);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.prefs__select {
  width: 100%;
  appearance: none;
  border: 1px solid var(--rule-2);
  border-radius: var(--r-sm);
  background: var(--bg);
  color: var(--ink);
  padding: 10px 12px;
  font-family: var(--sans);
  font-size: 13px;
  transition: border-color .2s var(--ease), box-shadow .2s var(--ease);
}
.prefs__select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent);
}
.toc__label {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 18px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--rule);
}
.toc__list { list-style: none; counter-reset: none; }
.toc__list li { margin-bottom: 6px; }
.toc__list a {
  display: block;
  color: var(--ink-dim);
  padding: 5px 0 5px 12px;
  border-left: 1px solid var(--rule);
  transition: all .2s var(--ease);
  font-weight: 500;
}
.toc__list a:hover { color: var(--ink); border-color: var(--ink-dim); text-decoration: none; }
.toc__list a.is-active { color: var(--accent); border-color: var(--accent); }
.toc__list ol {
  list-style: none;
  padding-left: 12px;
  margin-top: 4px;
  font-size: 13px;
}
.toc__list ol a { border-color: var(--rule); color: var(--ink-faint); }

.docs { min-width: 0; }
.doc-section + .doc-section { border-top: 1px solid var(--rule); }
.doc-section { padding: clamp(50px, 7vw, 90px) 0; }

.prose {
  font-family: var(--serif);
  font-size: 17px;
  color: var(--ink);
  max-width: 72ch;
}
.prose p { color: var(--ink); }
.prose em { color: var(--ink-dim); font-style: italic; }
.prose code {
  color: var(--accent-soft);
  background: rgba(255,180,84,0.08);
  padding: 1px 6px;
  border-radius: 3px;
  font-size: 0.84em;
}

/* ---------- steps ---------- */
.steps {
  list-style: none;
  counter-reset: steps;
  display: flex; flex-direction: column;
  gap: 28px;
  max-width: 72ch;
}
.steps li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 22px;
  align-items: start;
}
.steps__num {
  font-family: var(--mono);
  font-size: 14px;
  color: var(--accent);
  width: 36px; height: 36px;
  border: 1px solid color-mix(in srgb, var(--accent) 50%, transparent);
  border-radius: 50%;
  display: grid; place-items: center;
  font-weight: 600;
  background: rgba(255,122,26,0.04);
}
.steps h4 {
  font-family: var(--sans);
  font-size: 17px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 8px;
  display: flex; align-items: baseline; gap: 10px;
  flex-wrap: wrap;
}
.steps h4 code {
  font-size: 0.86em;
  background: none;
  color: var(--accent-soft);
  padding: 0;
}
.steps p {
  font-size: 16px;
  color: var(--ink-dim);
  margin-bottom: 14px;
}
.steps__flag {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--bg);
  background: var(--accent);
  padding: 2px 8px;
  border-radius: 2px;
  font-weight: 600;
}
.steps__flag--soft {
  background: transparent;
  color: var(--ink-faint);
  border: 1px solid var(--rule-2);
}

/* ---------- subsection ---------- */
.subsection {
  margin-top: 56px;
  padding-top: 36px;
  border-top: 1px dashed var(--rule-2);
}
.subsection:first-of-type { margin-top: 56px; }
.subsection__label {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 10px;
}
.subsection h3 {
  font-family: var(--display);
  font-weight: 400;
  font-style: italic;
  font-size: clamp(24px, 2.6vw, 32px);
  color: var(--ink);
  margin-bottom: 14px;
  max-width: 48ch;
  line-height: 1.15;
  text-wrap: balance;
}
.subsection h3 code {
  font-family: var(--mono);
  font-style: normal;
  font-size: 0.7em;
  color: var(--accent-soft);
  background: rgba(255,180,84,0.06);
  padding: 2px 8px;
  border-radius: 3px;
}
.subsection p {
  font-family: var(--serif);
  font-size: 16.5px;
  color: var(--ink-dim);
  max-width: 72ch;
  margin-bottom: 18px;
}
.subsection p code {
  font-size: 0.86em;
  color: var(--accent-soft);
  background: rgba(255,180,84,0.08);
  padding: 1px 6px;
  border-radius: 3px;
}

.muted-h {
  font-family: var(--mono) !important;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-size: 12px !important;
  color: var(--ink-faint) !important;
  border-top: 1px solid var(--rule);
  padding-top: 18px;
  margin-top: 24px !important;
}

/* ---------- code blocks ---------- */
pre {
  margin: 20px 0;
  padding: 0;
  background: var(--code-bg);
  border: 1px solid var(--rule-2);
  border-radius: var(--r);
  overflow: hidden;
  position: relative;
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.7;
}
pre code {
  display: block;
  padding: 22px 24px;
  overflow-x: auto;
  background: transparent !important;
  color: var(--ink);
  font-family: var(--mono);
  font-size: 13.5px;
  line-height: 1.7;
}
pre[class*="language-"] { text-shadow: none; }

/* scrollbar */
pre code::-webkit-scrollbar { height: 8px; }
pre code::-webkit-scrollbar-track { background: transparent; }
pre code::-webkit-scrollbar-thumb { background: var(--rule-2); border-radius: 4px; }

/* copy button on code */
.code-copy {
  position: absolute; top: 10px; right: 10px;
  font-family: var(--sans);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--rule-2);
  border-radius: 3px;
  padding: 5px 9px;
  opacity: 0;
  transition: all .2s var(--ease);
}
pre:hover .code-copy { opacity: 1; }
.code-copy:hover { color: var(--accent); border-color: var(--accent); }
.code-copy.is-copied { color: var(--bg); background: var(--accent); border-color: var(--accent); opacity: 1; }

.copy-inline {
  position: relative;
  margin-top: 14px;
  padding: 16px 52px 16px 16px;
  background: var(--code-bg);
  border: 1px solid var(--rule-2);
  border-radius: var(--r-sm);
}
.copy-inline .files__run {
  display: block;
  margin: 0;
  padding: 0;
  background: transparent;
  border: 0;
  color: var(--ink);
}
.code-copy--inline {
  opacity: 1;
  top: 12px;
  right: 12px;
}

/* ---------- Prism override (warm theme) ---------- */
code[class*="language-"], pre[class*="language-"] {
  color: var(--ink);
  background: var(--code-bg);
  text-shadow: none;
  font-family: var(--mono);
}
.token.comment, .token.prolog, .token.doctype, .token.cdata {
  color: #5C5342; font-style: italic;
}
.token.punctuation { color: var(--ink-faint); }
.token.keyword, .token.selector, .token.important, .token.atrule {
  color: var(--accent); font-weight: 500;
}
.token.function, .token.class-name, .token.builtin {
  color: #E8C88A;
}
.token.string, .token.char, .token.attr-value, .token.regex {
  color: #B8D4A8;
}
.token.number, .token.boolean { color: #FFB454; }
.token.operator, .token.entity, .token.url, .token.variable {
  color: var(--ink-dim);
}
.token.property, .token.tag, .token.constant, .token.symbol, .token.deleted {
  color: #FF9B6B;
}

/* ---------- callouts ---------- */
.callout {
  margin: 24px 0;
  padding: 18px 22px 4px 22px;
  border-left: 3px solid var(--accent);
  background: rgba(255,122,26,0.04);
  border-radius: 0 var(--r) var(--r) 0;
  font-family: var(--serif);
  font-size: 16px;
  color: var(--ink);
}
.callout__label {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 6px;
}
.callout p { color: var(--ink); }
.callout--warn { border-left-color: #E8C88A; background: rgba(232,200,138,0.05); }
.callout--warn .callout__label { color: #E8C88A; }
.callout pre { margin-top: 12px; }

/* ---------- notes ---------- */
.notes {
  display: grid;
  gap: 24px;
  max-width: 72ch;
}
.note {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 20px;
  padding: 24px 0;
  border-top: 1px solid var(--rule);
}
.note:last-child { border-bottom: 1px solid var(--rule); }
.note__num {
  font-family: var(--display);
  font-style: italic;
  font-size: 44px;
  color: var(--accent);
  line-height: 1;
}
.note__body h4 {
  font-family: var(--sans);
  font-size: 17px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 8px;
}
.note__body p {
  font-size: 16px;
  color: var(--ink-dim);
  margin: 0;
}

/* ---------- files list ---------- */
.files {
  list-style: none;
  display: grid;
  gap: 14px;
  max-width: 72ch;
}
.files li {
  padding: 20px 24px;
  border: 1px solid var(--rule);
  border-radius: var(--r);
  background: transparent;
  transition: border-color .25s var(--ease);
}
.files li:hover {
  border-color: var(--accent-deep);
}
.files__head {
  display: flex; justify-content: space-between; align-items: center;
  gap: 14px;
  margin-bottom: 8px;
  flex-wrap: wrap;
}
.files__path {
  font-family: var(--mono);
  font-size: 14px;
  color: var(--ink);
  font-weight: 500;
}
.ext-link::after {
  content: " ↗";
  color: var(--accent);
  font-size: 0.9em;
  white-space: nowrap;
}
.files__pill {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  border: 1px solid color-mix(in srgb, var(--accent) 40%, transparent);
  padding: 3px 10px;
  border-radius: 30px;
}
.files p {
  font-family: var(--serif);
  font-size: 15px;
  color: var(--ink-dim);
  margin: 0 0 10px;
}
.files__run {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12.5px;
  color: var(--accent-soft);
  background: rgba(255,180,84,0.06);
  padding: 6px 10px;
  border-radius: 3px;
  border: 1px dashed var(--rule-2);
}

/* ---------- platforms ---------- */
.plat-grid {
  max-width: 960px; margin: 0 auto;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 1px;
  background: var(--rule);
  border: 1px solid var(--rule);
}
.plat-grid li {
  background: var(--bg);
  padding: 34px 20px;
  display: flex; flex-direction: column; gap: 14px; align-items: center; text-align: center;
  transition: background .25s var(--ease);
  position: relative;
}
.plat-grid li:hover { background: #16130E; }
.plat-grid li:hover .plat__name { color: var(--accent); }
.plat__num {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-faint);
  letter-spacing: 0.2em;
}
.plat__name {
  font-family: var(--display);
  font-style: italic;
  font-size: 26px;
  color: var(--ink);
  transition: color .25s var(--ease);
}
.plat__engine {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-dim);
  letter-spacing: 0.06em;
}

/* ---------- cta ---------- */
.cta {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(40px, 6vw, 80px) var(--gutter) clamp(60px, 8vw, 120px);
}
.cta__card {
  border: 1px solid var(--rule-2);
  border-radius: var(--r-lg);
  padding: clamp(32px, 5vw, 60px);
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
  gap: clamp(32px, 5vw, 72px);
  align-items: center;
  background:
    radial-gradient(ellipse at 0% 100%, rgba(255,122,26,0.08), transparent 60%),
    var(--bg-2);
}
.cta__left h2 { margin: 10px 0 14px; }
.cta__left p {
  font-family: var(--serif);
  font-size: 17px;
  color: var(--ink-dim);
  max-width: 52ch;
  margin-bottom: 24px;
}
.cta__buttons { display: flex; gap: 12px; flex-wrap: wrap; }
.ascii {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--accent-soft);
  background: var(--code-bg);
  border: 1px solid var(--rule-2);
  border-radius: var(--r-sm);
  padding: 18px 22px;
  line-height: 1.5;
  white-space: pre;
  overflow-x: auto;
}
.ascii pre { border: 0; padding: 0; margin: 0; background: transparent; font-size: 11px; color: inherit; }

/* ---------- footer ---------- */
.foot {
  border-top: 1px solid var(--rule);
  background: var(--bg-2);
}
.foot__inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 56px var(--gutter) 32px;
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 2fr);
  gap: 48px;
}
.foot__brand p {
  margin-top: 14px;
  font-family: var(--serif);
  font-size: 15px;
  color: var(--ink-dim);
  max-width: 40ch;
}
.foot__brand a { color: var(--ink); text-decoration: underline; text-underline-offset: 3px; }
.foot__nav {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}
.foot__nav h5 {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}
.foot__nav a {
  display: block;
  font-family: var(--sans);
  font-size: 14px;
  color: var(--ink-dim);
  padding: 4px 0;
  transition: color .2s var(--ease);
  text-decoration: none;
}
.foot__nav a:hover { color: var(--ink); }
.foot__rule {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 22px var(--gutter);
  border-top: 1px solid var(--rule);
  display: flex; justify-content: space-between; gap: 18px;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-faint);
  letter-spacing: 0.06em;
  flex-wrap: wrap;
}
.foot__mark { font-style: italic; font-family: var(--serif); letter-spacing: 0; }

/* ---------- reveal animation ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
}
[data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- responsive ---------- */
@media (max-width: 1080px) {
  .hero__inner { grid-template-columns: minmax(0, 1fr); }
  .panel { transform: none; }
  .hero__right { order: -1; max-width: 640px; }
  .layout { grid-template-columns: 1fr; }
  .toc { position: static; border-bottom: 1px solid var(--rule); padding-bottom: 20px; margin-bottom: 20px; }
  .toc__prefs { max-width: 420px; }
}
@media (max-width: 900px) {
  .nav, .topbar__actions .btn--ghost, .topbar__prefs { display: none; }
  .topbar__inner { grid-template-columns: auto 1fr auto; gap: 12px; }
  .nav-toggle { display: flex; }
  .topbar.is-open .nav {
    display: flex; flex-direction: column; position: absolute; top: 100%; left: 0; right: 0;
    background: var(--bg); padding: 24px var(--gutter); border-bottom: 1px solid var(--rule);
    gap: 16px;
  }
  .cta__card { grid-template-columns: 1fr; }
  .cta__right { display: none; }
  .plat-grid { grid-template-columns: repeat(2, 1fr); }
  .foot__inner { grid-template-columns: 1fr; }
  .foot__nav { grid-template-columns: repeat(3, 1fr); gap: 20px; }
  .foot__rule { justify-content: flex-start; }
  .hero__meta { grid-template-columns: 1fr; gap: 12px; }
  .hero__meta li { border-right: 0; border-bottom: 1px solid var(--rule); padding-bottom: 12px; }
  .hero__meta li:last-child { border-bottom: 0; }
}
@media (max-width: 560px) {
  .plat-grid { grid-template-columns: 1fr; }
  .foot__nav { grid-template-columns: 1fr 1fr; }
  .note { grid-template-columns: 40px 1fr; gap: 14px; }
  .note__num { font-size: 32px; }
  .panel__code { font-size: 11.5px; padding: 14px 14px; }
  .rule span { font-size: 18px; padding: 0 12px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .marquee__track { animation: none !important; }
}