/* =========================================================
   CodeJumbo LLC — site styles
   Design notes: warm paper + ink, a highlighter-marker accent
   borrowed from the way people actually study, and a violet
   used only for things you can interact with.
   ========================================================= */

/* ---------- tokens ---------- */

:root {
  --paper:        #FBF9F4;
  --paper-2:      #F2EEE5;
  --paper-3:      #E7E1D4;
  --ink:          #16150F;
  --ink-2:        #4A4740;
  --ink-3:        #77726A;
  --line:         #DED8CA;
  --marker:       #D8F24B;
  --marker-soft:  #EDF9A8;
  --violet:       #4B31E0;
  --violet-soft:  #EAE6FF;

  --shadow-sm: 0 1px 2px rgba(22, 21, 15, .05), 0 4px 14px -6px rgba(22, 21, 15, .10);
  --shadow-md: 0 2px 4px rgba(22, 21, 15, .05), 0 18px 40px -18px rgba(22, 21, 15, .28);

  --font-sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Inter, Roboto,
               "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas,
               "Liberation Mono", monospace;

  --wrap: 1180px;
  --gutter: clamp(1.25rem, 5vw, 3.5rem);
  --radius: 14px;
  --header-h: 68px;
}

:root[data-theme="dark"] {
  --paper:        #100F0C;
  --paper-2:      #191813;
  --paper-3:      #23211A;
  --ink:          #F4F1E8;
  --ink-2:        #B6B1A4;
  --ink-3:        #8B857A;
  --line:         #2E2B23;
  --marker:       #D8F24B;
  --marker-soft:  #3A4416;
  --violet:       #A392FF;
  --violet-soft:  #24204A;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, .4), 0 4px 14px -6px rgba(0, 0, 0, .6);
  --shadow-md: 0 2px 4px rgba(0, 0, 0, .4), 0 18px 40px -18px rgba(0, 0, 0, .9);
}

/* ---------- reset ---------- */

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

* { margin: 0; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 1.5rem);
}

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  letter-spacing: -0.005em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

img, svg { display: block; max-width: 100%; }
button, input, textarea, select { font: inherit; color: inherit; }
a { color: inherit; }

:focus-visible {
  outline: 2px solid var(--violet);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: var(--marker);
  color: #16150F;
}

/* ---------- primitives ---------- */

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.skip {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 100;
  background: var(--ink);
  color: var(--paper);
  padding: .75rem 1.25rem;
  border-radius: 0 0 8px 0;
}
.skip:focus { left: 0; }

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--ink-3);
  display: flex;
  align-items: center;
  gap: .6rem;
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--ink-3);
  flex: none;
}

h1, h2, h3, h4 {
  line-height: 1.04;
  letter-spacing: -0.035em;
  font-weight: 640;
  text-wrap: balance;
}

h1 { font-size: clamp(2.6rem, 6.4vw, 4.6rem); }
h2 { font-size: clamp(2rem, 4.2vw, 3.1rem); }
h3 { font-size: clamp(1.25rem, 2vw, 1.55rem); letter-spacing: -0.025em; }

p { text-wrap: pretty; }

.lede {
  font-size: clamp(1.05rem, 1.6vw, 1.28rem);
  line-height: 1.55;
  color: var(--ink-2);
  max-width: 46ch;
}

/* the highlighter — drawn behind the text, slightly off-kilter */
.mark {
  position: relative;
  display: inline-block;
  isolation: isolate;
  white-space: nowrap;
}
.mark::after {
  content: "";
  position: absolute;
  z-index: -1;
  left: -.12em;
  right: -.12em;
  bottom: .04em;
  height: .46em;
  background: var(--marker);
  transform: rotate(-.6deg);
  transform-origin: left center;
  border-radius: 2px 8px 4px 6px;
  transition: height .5s cubic-bezier(.2, .8, .2, 1);
}
/* On dark the highlight sits under light text, so it drops to a wash
   instead of a solid stripe — a solid lime would swallow the letters. */
:root[data-theme="dark"] .mark::after {
  background: color-mix(in srgb, var(--marker) 30%, transparent);
  box-shadow: 0 0 0 1px color-mix(in srgb, var(--marker) 22%, transparent);
}

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: .55rem;
  padding: .8rem 1.35rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: .95rem;
  font-weight: 560;
  letter-spacing: -0.01em;
  text-decoration: none;
  cursor: pointer;
  transition: transform .18s cubic-bezier(.2, .8, .2, 1),
              background-color .18s ease, border-color .18s ease, color .18s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--ink);
  color: var(--paper);
}
.btn--primary:hover { background: var(--violet); color: #fff; }
:root[data-theme="dark"] .btn--primary:hover { color: #100F0C; }

.btn--ghost {
  border-color: var(--line);
  background: transparent;
  color: var(--ink);
}
.btn--ghost:hover { border-color: var(--ink); background: var(--paper-2); }

.btn .arrow { transition: transform .22s cubic-bezier(.2, .8, .2, 1); }
.btn:hover .arrow { transform: translateX(3px); }

/* ---------- header ---------- */

.header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  display: flex;
  align-items: center;
  background: color-mix(in srgb, var(--paper) 82%, transparent);
  backdrop-filter: saturate(1.6) blur(14px);
  -webkit-backdrop-filter: saturate(1.6) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s ease, background-color .25s ease;
}
.header.is-stuck { border-bottom-color: var(--line); }

.header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: .6rem;
  text-decoration: none;
  font-weight: 640;
  letter-spacing: -0.03em;
  font-size: 1.08rem;
}
.brand svg { flex: none; }
.brand .llc {
  font-family: var(--font-mono);
  font-size: .625rem;
  letter-spacing: .12em;
  color: var(--ink-3);
  align-self: flex-start;
  margin-top: .18rem;
}

.nav {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 2.4vw, 2rem);
}
.nav a {
  text-decoration: none;
  font-size: .93rem;
  color: var(--ink-2);
  position: relative;
  padding: .25rem 0;
  transition: color .18s ease;
}
.nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--marker);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .25s cubic-bezier(.2, .8, .2, 1);
}
.nav a:hover { color: var(--ink); }
.nav a:hover::after { transform: scaleX(1); }

.header-actions {
  display: flex;
  align-items: center;
  gap: .6rem;
}

.icon-btn {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: transparent;
  cursor: pointer;
  transition: background-color .18s ease, border-color .18s ease;
}
.icon-btn:hover { background: var(--paper-2); border-color: var(--ink-3); }
.icon-btn .moon { display: none; }
:root[data-theme="dark"] .icon-btn .sun { display: none; }
:root[data-theme="dark"] .icon-btn .moon { display: block; }

.nav-toggle { display: none; }

/* ---------- hero ---------- */

.hero {
  padding-top: clamp(3.5rem, 9vw, 6.5rem);
  padding-bottom: clamp(3rem, 7vw, 5rem);
  position: relative;
  overflow: hidden;
}

/* faint ruled-paper grid, fading out downward */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line) 1px, transparent 1px);
  background-size: 64px 64px;
  opacity: .5;
  -webkit-mask-image: radial-gradient(120% 90% at 15% 0%, #000 0%, transparent 72%);
          mask-image: radial-gradient(120% 90% at 15% 0%, #000 0%, transparent 72%);
  pointer-events: none;
}

.hero .wrap {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  align-items: center;
}

.hero h1 { margin: 1.4rem 0 1.5rem; }
.hero .lede { margin-bottom: 2.25rem; }

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
  align-items: center;
}

.hero-note {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: .76rem;
  letter-spacing: .04em;
  color: var(--ink-3);
  display: flex;
  flex-wrap: wrap;
  gap: .5rem 1.4rem;
}
.hero-note span { display: inline-flex; align-items: center; gap: .45rem; }
.hero-note span::before {
  content: "";
  width: 5px;
  height: 5px;
  border-radius: 999px;
  background: var(--marker);
}

/* ---------- hero demo card ---------- */

.demo {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: var(--shadow-md);
  padding: 1.4rem;
  position: relative;
  transform: rotate(.5deg);
}
/* the stacked "deck" behind the card */
.demo::before,
.demo::after {
  content: "";
  position: absolute;
  inset: 0;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--paper);
  z-index: -1;
}
.demo::before { transform: rotate(-2.2deg) translateY(6px); }
.demo::after  { transform: rotate(-4.4deg) translateY(12px); opacity: .6; }

.demo-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1rem;
}
.demo-streak {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  color: var(--ink-2);
}
.demo-streak b {
  font-family: var(--font-sans);
  font-size: .85rem;
  letter-spacing: -0.01em;
}

.demo-progress {
  height: 6px;
  border-radius: 999px;
  background: var(--paper-3);
  overflow: hidden;
  margin-bottom: 1.35rem;
}
.demo-progress i {
  display: block;
  height: 100%;
  width: 20%;
  border-radius: 999px;
  background: var(--marker);
  transition: width .7s cubic-bezier(.2, .8, .2, 1);
}

.demo-q {
  font-size: 1.12rem;
  font-weight: 560;
  letter-spacing: -0.02em;
  line-height: 1.35;
  margin-bottom: 1.1rem;
  min-height: 3em;
}

.demo-opts {
  display: grid;
  gap: .5rem;
  list-style: none;
  padding: 0;
}
.demo-opts li {
  display: flex;
  align-items: center;
  gap: .7rem;
  padding: .68rem .85rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  font-size: .95rem;
  color: var(--ink-2);
  transition: background-color .3s ease, border-color .3s ease, color .3s ease;
}
.demo-opts li .key {
  font-family: var(--font-mono);
  font-size: .7rem;
  width: 22px;
  height: 22px;
  flex: none;
  display: grid;
  place-items: center;
  border-radius: 6px;
  background: var(--paper-2);
  color: var(--ink-3);
  transition: background-color .3s ease, color .3s ease;
}
.demo-opts li.is-picked {
  border-color: var(--ink-3);
  background: var(--paper-2);
  color: var(--ink);
}
.demo-opts li.is-right {
  border-color: color-mix(in srgb, var(--marker) 70%, var(--ink) 30%);
  background: var(--marker-soft);
  color: var(--ink);
}
.demo-opts li.is-right .key {
  background: var(--marker);
  color: #16150F;
}

.demo-foot {
  margin-top: 1.15rem;
  padding-top: .9rem;
  border-top: 1px dashed var(--line);
  font-family: var(--font-mono);
  font-size: .72rem;
  color: var(--ink-3);
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}
.demo-foot .tag {
  color: var(--violet);
}

/* ---------- marquee ---------- */

.marquee {
  border-block: 1px solid var(--line);
  background: var(--paper-2);
  overflow: hidden;
  padding: .85rem 0;
  --speed: 42s;
}
.marquee-track {
  display: flex;
  width: max-content;
  animation: slide var(--speed) linear infinite;
}
.marquee:hover .marquee-track { animation-play-state: paused; }
.marquee-track span {
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--ink-2);
  padding-inline: 1.6rem;
  display: inline-flex;
  align-items: center;
  gap: 1.6rem;
  white-space: nowrap;
}
.marquee-track span::after {
  content: "";
  width: 6px;
  height: 6px;
  background: var(--marker);
  transform: rotate(45deg);
}
@keyframes slide {
  from { transform: translateX(0); }
  to   { transform: translateX(-50%); }
}

/* ---------- sections ---------- */

.section {
  padding-block: clamp(4rem, 9vw, 7.5rem);
  border-bottom: 1px solid var(--line);
}
.section--flat { border-bottom: 0; }
.section--tint { background: var(--paper-2); }

.section-head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, .8fr);
  gap: clamp(1.5rem, 4vw, 4rem);
  align-items: end;
  margin-bottom: clamp(2.5rem, 5vw, 4rem);
}
.section-head h2 { margin-top: 1rem; }
.section-head p { color: var(--ink-2); }

/* numbered capability rows — deliberately asymmetric, not a card grid */
.rows { border-top: 1px solid var(--line); }

.row {
  display: grid;
  grid-template-columns: 4.5rem minmax(0, 1fr) minmax(0, 1.15fr);
  gap: clamp(1rem, 3vw, 2.5rem);
  padding-block: clamp(1.75rem, 3.5vw, 2.6rem);
  border-bottom: 1px solid var(--line);
  position: relative;
  transition: background-color .3s ease;
}
.row::before {
  content: "";
  position: absolute;
  left: calc(var(--gutter) * -1);
  right: calc(var(--gutter) * -1);
  top: 0;
  bottom: 0;
  background: var(--paper-2);
  opacity: 0;
  transition: opacity .3s ease;
  z-index: -1;
}
.row:hover::before { opacity: 1; }

.row-num {
  font-family: var(--font-mono);
  font-size: .8rem;
  letter-spacing: .1em;
  color: var(--ink-3);
  padding-top: .45rem;
}
.row-title { display: flex; flex-direction: column; gap: .75rem; }
.row-body { color: var(--ink-2); }
.row-body p + .tags { margin-top: 1.15rem; }

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: .45rem;
  list-style: none;
  padding: 0;
}
.tags li {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .04em;
  padding: .3rem .6rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--ink-3);
  background: var(--paper);
}

/* principles */
.principles {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.principle {
  background: var(--paper);
  padding: clamp(1.5rem, 3vw, 2.15rem);
  display: flex;
  flex-direction: column;
  gap: .7rem;
  transition: background-color .3s ease;
}
.principle:hover { background: var(--paper-2); }
.principle .glyph {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 9px;
  background: var(--marker-soft);
  color: var(--ink);
  margin-bottom: .35rem;
}
:root[data-theme="dark"] .principle .glyph { color: var(--marker); }
.principle h3 { font-size: 1.08rem; }
.principle p { color: var(--ink-2); font-size: .95rem; }

/* process steps */
.steps {
  counter-reset: step;
  display: grid;
  gap: clamp(1.5rem, 3vw, 2.25rem);
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  list-style: none;
  padding: 0;
}
.steps li {
  counter-increment: step;
  padding-top: 1.5rem;
  border-top: 2px solid var(--ink);
  position: relative;
}
.steps li::before {
  content: counter(step, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .1em;
  color: var(--ink-3);
  display: block;
  margin-bottom: .8rem;
}
.steps h3 { margin-bottom: .6rem; }
.steps p { color: var(--ink-2); font-size: .97rem; }

/* about split */
.split {
  display: grid;
  grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr);
  gap: clamp(2rem, 6vw, 5rem);
  align-items: start;
}
.split .prose p + p { margin-top: 1.15rem; }
.split .prose p { color: var(--ink-2); }

.facts {
  display: grid;
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  overflow: hidden;
}
.facts div {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1.5rem;
  padding: .95rem 1.25rem;
  border-bottom: 1px solid var(--line);
  font-size: .95rem;
}
.facts div:last-child { border-bottom: 0; }
.facts dt {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.facts dd { margin: 0; text-align: right; color: var(--ink); }
.facts a { color: var(--violet); text-decoration-thickness: 1px; text-underline-offset: 3px; }

/* contact band */
.cta {
  border: 1px solid var(--ink);
  border-radius: clamp(16px, 3vw, 26px);
  padding: clamp(2rem, 5vw, 4rem);
  background: var(--ink);
  color: var(--paper);
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: center;
  position: relative;
  overflow: hidden;
}
.cta::after {
  content: "";
  position: absolute;
  right: -80px;
  top: -80px;
  width: 260px;
  height: 260px;
  border-radius: 50%;
  background: var(--violet);
  opacity: .28;
  filter: blur(50px);
  pointer-events: none;
}
.cta h2 { color: var(--paper); }
.cta p {
  color: color-mix(in srgb, var(--paper) 72%, transparent);
  margin-top: .9rem;
  max-width: 44ch;
}
.cta .eyebrow { color: color-mix(in srgb, var(--paper) 60%, transparent); }
.cta .eyebrow::before { background: var(--marker); }
.cta .btn--primary { background: var(--marker); color: #16150F; }
.cta .btn--primary:hover { background: var(--paper); color: var(--ink); }
.cta-actions { display: grid; gap: .75rem; justify-items: start; position: relative; }
.cta-mail {
  font-family: var(--font-mono);
  font-size: .8rem;
  color: color-mix(in srgb, var(--paper) 62%, transparent);
  text-decoration: none;
}
.cta-mail:hover { color: var(--marker); }

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

.footer {
  padding-block: clamp(2.5rem, 5vw, 4rem) 2.25rem;
  border-top: 1px solid var(--line);
}
.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) repeat(2, minmax(0, 1fr));
  gap: clamp(1.75rem, 4vw, 3rem);
  padding-bottom: 2.5rem;
}
.footer-top p {
  color: var(--ink-3);
  font-size: .93rem;
  max-width: 34ch;
  margin-top: .9rem;
}
.footer h4 {
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 500;
  letter-spacing: .13em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1rem;
}
.footer ul { list-style: none; padding: 0; display: grid; gap: .55rem; }
.footer ul a {
  text-decoration: none;
  font-size: .95rem;
  color: var(--ink-2);
  transition: color .18s ease;
}
.footer ul a:hover { color: var(--ink); text-decoration: underline; text-underline-offset: 4px; }

.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 1.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: .75rem 1.5rem;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .04em;
  color: var(--ink-3);
}

/* ---------- legal documents ---------- */

.doc-hero {
  padding-top: clamp(2.5rem, 6vw, 4.5rem);
  padding-bottom: clamp(1.75rem, 4vw, 2.75rem);
  border-bottom: 1px solid var(--line);
}
.doc-hero h1 {
  font-size: clamp(2.1rem, 5vw, 3.4rem);
  margin: 1.1rem 0 1.1rem;
}
.doc-meta {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem 1.5rem;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .06em;
  color: var(--ink-3);
}

.doc-layout {
  display: grid;
  grid-template-columns: 230px minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 4.5rem);
  padding-block: clamp(2.5rem, 5vw, 4rem) clamp(3.5rem, 7vw, 6rem);
  align-items: start;
}

.toc {
  position: sticky;
  top: calc(var(--header-h) + 2rem);
  max-height: calc(100vh - var(--header-h) - 4rem);
  overflow-y: auto;
}
.toc h2 {
  font-family: var(--font-mono);
  font-size: .7rem;
  font-weight: 500;
  letter-spacing: .13em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1rem;
  letter-spacing: .13em;
}
.toc ol {
  list-style: none;
  padding: 0;
  counter-reset: toc;
  display: grid;
  gap: .1rem;
  border-left: 1px solid var(--line);
}
.toc li { counter-increment: toc; }
.toc a {
  display: block;
  padding: .34rem .8rem;
  margin-left: -1px;
  border-left: 2px solid transparent;
  font-size: .855rem;
  line-height: 1.35;
  color: var(--ink-3);
  text-decoration: none;
  transition: color .18s ease, border-color .18s ease;
}
.toc a::before {
  content: counter(toc) ". ";
  font-family: var(--font-mono);
  font-size: .72rem;
  opacity: .7;
}
.toc a:hover { color: var(--ink); }
.toc a.is-active {
  color: var(--ink);
  border-left-color: var(--marker);
  font-weight: 550;
}

.doc { max-width: 68ch; }
.doc > section { scroll-margin-top: calc(var(--header-h) + 2rem); }
.doc > section + section { margin-top: clamp(2.5rem, 5vw, 3.5rem); }
.doc h2 {
  font-size: clamp(1.35rem, 2.4vw, 1.75rem);
  margin-bottom: 1rem;
  display: flex;
  gap: .7rem;
  align-items: baseline;
}
.doc h2 .n {
  font-family: var(--font-mono);
  font-size: .8rem;
  letter-spacing: .06em;
  color: var(--ink-3);
  flex: none;
}
.doc h3 {
  font-size: 1.05rem;
  margin: 1.75rem 0 .6rem;
}
.doc p, .doc li { color: var(--ink-2); }
.doc p + p { margin-top: 1rem; }
.doc ul, .doc ol { margin: 1rem 0; padding-left: 1.35rem; display: grid; gap: .5rem; }
.doc li::marker { color: var(--ink-3); }
.doc a { color: var(--violet); text-underline-offset: 3px; }
.doc strong { color: var(--ink); font-weight: 600; }

.callout {
  border: 1px solid var(--line);
  border-left: 3px solid var(--marker);
  background: var(--paper-2);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 1.15rem 1.35rem;
  margin: 1.5rem 0;
}
.callout p { color: var(--ink-2); font-size: .95rem; }
.callout .label {
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--ink-3);
  display: block;
  margin-bottom: .5rem;
}

.doc-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.35rem 0;
  font-size: .92rem;
  display: block;
  overflow-x: auto;
  white-space: nowrap;
}
.doc-table th, .doc-table td {
  text-align: left;
  padding: .7rem .9rem;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
.doc-table th {
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--ink-3);
  font-weight: 500;
}
.doc-table td { color: var(--ink-2); }
@media (min-width: 720px) {
  .doc-table { display: table; white-space: normal; }
}

/* ---------- 404 ---------- */

.notfound {
  min-height: calc(100vh - var(--header-h) - 120px);
  display: grid;
  place-items: center;
  text-align: center;
  padding-block: clamp(3rem, 10vw, 7rem);
}
.notfound .code {
  font-family: var(--font-mono);
  font-size: clamp(4rem, 16vw, 9rem);
  line-height: 1;
  letter-spacing: -0.06em;
  color: var(--ink);
}
.notfound p { color: var(--ink-2); margin: 1.25rem auto 2rem; max-width: 40ch; }

/* ---------- reveal on scroll ---------- */

.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .7s cubic-bezier(.2, .8, .2, 1),
              transform .7s cubic-bezier(.2, .8, .2, 1);
}
.reveal.is-in { opacity: 1; transform: none; }

/* ---------- responsive ---------- */

@media (max-width: 980px) {
  .hero .wrap { grid-template-columns: 1fr; }
  .demo { transform: none; max-width: 520px; }
  .section-head { grid-template-columns: 1fr; align-items: start; }
  .split { grid-template-columns: 1fr; }
  .cta { grid-template-columns: 1fr; }
  .doc-layout { grid-template-columns: 1fr; }
  .toc {
    position: static;
    max-height: none;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 1.15rem 1.25rem;
    background: var(--paper-2);
  }
  .toc ol { grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); }
  .footer-top { grid-template-columns: 1fr 1fr; }
  .footer-top > :first-child { grid-column: 1 / -1; }
}

@media (max-width: 720px) {
  :root { --header-h: 60px; }

  .nav-toggle { display: grid; }

  .nav {
    position: fixed;
    inset: var(--header-h) 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    padding: .5rem var(--gutter) 1.25rem;
    box-shadow: var(--shadow-md);
    transform: translateY(-8px);
    opacity: 0;
    visibility: hidden;
    transition: opacity .2s ease, transform .2s ease, visibility .2s;
  }
  .nav[data-open="true"] {
    opacity: 1;
    visibility: visible;
    transform: none;
  }
  .nav a {
    padding: .85rem 0;
    border-bottom: 1px solid var(--line);
    font-size: 1.02rem;
    color: var(--ink);
  }
  .nav a::after { display: none; }

  .row { grid-template-columns: 1fr; gap: .9rem; }
  .row-num { padding-top: 0; }
  .hero-cta .btn { flex: 1 1 auto; justify-content: center; }
  .footer-top { grid-template-columns: 1fr; }
  .facts div { flex-direction: column; gap: .25rem; }
  .facts dd { text-align: left; }
}

/* ---------- motion & print ---------- */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  .reveal { opacity: 1; transform: none; }
}

@media print {
  .header, .footer, .toc, .marquee, .cta { display: none !important; }
  body { background: #fff; color: #000; font-size: 11pt; }
  .doc-layout { grid-template-columns: 1fr; padding: 0; }
  .doc { max-width: none; }
  a { text-decoration: underline; }
}