/* =====================================================================
   The GTM Blueprint  ::  Siddharth Jain
   Design system: "inverted blueprint" - deep ink-blue ground, paper-white
   linework, one warm accent. Editorial display + humanist body + mono for
   technical annotations. Restrained, high-impact motion.

   COMPONENT VOCABULARY (use only these classes in page markup)
   ------------------------------------------------------------------
   Layout     .wrap  .section  .section--tight  .section--hero  .rule
   Header/nav .site-header  .nav  .wordmark  .wordmark__mark  .wordmark__full
              .nav__links  .nav__toggle  .nav__cta  .is-open
   Buttons    .btn  .btn--primary  .btn--ghost  .btn--text  .link
   Labels     .eyebrow  .annot  .measure  .section-title  .section-title--xl
              .lede  .kicker
   Numbers    .proofbar  .stat  .stat__num  .stat__label
              .callout  .callout__num  .callout__label  .callout__src
   Cards      .card-grid  .card  .case  .case__*  .pcard  .pcard__*
   Schematic  .timeline  .phase  .phase__index  .phase__title  .phase__weeks
              .phase__list  .blueprint-line (svg path draw)
   Compare    .versus  .versus__col  .versus__tag   .fit  .fit__col
   Content    .prose  (styles h2/h3/p/ul/ol/blockquote/figure inside)
   Accordion  .faq  .faq__item  .faq__answer  (native details/summary)
   Sections   .hero  .problem  .about  .final-cta  .breadcrumb  .capture
   Footer     .site-footer
   Motion     [data-reveal] + .reveal   [data-count] (+ data-suffix/decimals)
   ===================================================================== */

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

:root {
  /* --- palette: inverted blueprint --- */
  --ground:     #0B2138;
  --ground-2:   #0E2A47;
  --ground-3:   #123459;
  --line:       rgba(176,206,238,0.16);
  --line-2:     rgba(176,206,238,0.34);
  --line-3:     rgba(176,206,238,0.55);
  --paper:      #EAF2FB;
  --paper-soft: #C3D4E8;
  --paper-mute: #8EA4C2;
  --accent:     #FF6A3D;
  --accent-2:   #FF8C61;
  --accent-ink: #1A0B04;
  --accent-soft:rgba(255,106,61,0.14);

  /* --- type --- */
  --font-display: "Fraunces", Georgia, "Times New Roman", serif;
  --font-body:    "Hanken Grotesk", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono:    "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;

  /* fluid type scale */
  --step--2: clamp(0.72rem, 0.69rem + 0.15vw, 0.80rem);
  --step--1: clamp(0.84rem, 0.80rem + 0.20vw, 0.95rem);
  --step-0:  clamp(1.00rem, 0.95rem + 0.25vw, 1.13rem);
  --step-1:  clamp(1.22rem, 1.12rem + 0.50vw, 1.55rem);
  --step-2:  clamp(1.55rem, 1.35rem + 1.00vw, 2.20rem);
  --step-3:  clamp(2.00rem, 1.65rem + 1.75vw, 3.20rem);
  --step-4:  clamp(2.60rem, 2.00rem + 3.00vw, 4.60rem);
  --step-5:  clamp(3.30rem, 2.30rem + 5.00vw, 6.40rem);

  /* layout */
  --wrap: 1200px;
  --gutter: clamp(1.15rem, 4vw, 3rem);
  --header-h: 72px;

  --radius: 4px;
  --grid-size: 30px;
}

/* ---------------------------------------------------------------- base */
body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.65;
  color: var(--paper);
  background-color: var(--ground);
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: var(--grid-size) var(--grid-size);
  background-position: center top;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
/* atmospheric depth over the grid */
body::before {
  content: "";
  position: fixed; inset: 0; z-index: -1; pointer-events: none;
  background:
    radial-gradient(1100px 700px at 78% -10%, rgba(255,106,61,0.10), transparent 60%),
    radial-gradient(1000px 800px at 8% 105%, rgba(61,120,200,0.16), transparent 60%);
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }
ul, ol { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4 {
  margin: 0; font-family: var(--font-display); font-weight: 700;
  line-height: 1.1; letter-spacing: -0.015em; font-optical-sizing: auto;
}

::selection { background: var(--accent); color: var(--accent-ink); }

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

.skip-link {
  position: absolute; left: 50%; top: -60px; transform: translateX(-50%);
  background: var(--accent); color: var(--accent-ink);
  padding: .6rem 1.1rem; border-radius: 0 0 var(--radius) var(--radius);
  font-weight: 700; z-index: 200; transition: top .2s ease;
}
.skip-link:focus { top: 0; }

[id] { scroll-margin-top: calc(var(--header-h) + 24px); }

/* ------------------------------------------------------------- layout */
.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: var(--gutter); }
.section { padding-block: clamp(3.5rem, 8vw, 7rem); position: relative; }
.section--tight { padding-block: clamp(2.5rem, 5vw, 4rem); }
.section--hero { padding-block: clamp(4rem, 10vw, 8rem) clamp(2.5rem, 6vw, 4.5rem); }
.rule { height: 1px; background: var(--line-2); border: 0; margin: 0; }

/* hairline between major sections */
.section + .section { border-top: 1px solid var(--line); }

/* --------------------------------------------------------- header/nav */
.site-header {
  position: sticky; top: 0; z-index: 100;
  height: var(--header-h);
  background: rgba(11,33,56,0.78);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s ease, background .25s ease;
}
.site-header.is-stuck { border-bottom-color: var(--line-2); background: rgba(11,33,56,0.92); }
.nav {
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  height: 100%;
}
.wordmark { display: inline-flex; align-items: center; gap: .6rem; text-decoration: none; color: var(--paper); }
.wordmark__mark {
  font-family: var(--font-mono); font-weight: 600; font-size: .72rem; letter-spacing: .08em;
  color: var(--accent-ink); background: var(--accent);
  padding: .34rem .42rem; border-radius: 3px; line-height: 1;
}
.wordmark__full { font-family: var(--font-display); font-weight: 600; font-size: 1.12rem; letter-spacing: -.01em; }

.nav__links { display: flex; align-items: center; gap: clamp(1rem, 2vw, 1.9rem); }
.nav__links a {
  font-size: var(--step--1); font-weight: 500; color: var(--paper-soft);
  text-decoration: none; letter-spacing: .01em; transition: color .18s ease;
}
.nav__links a:hover, .nav__links a[aria-current="page"] { color: var(--paper); }
.nav__cta { margin-left: .4rem; }

.nav__toggle {
  display: none; background: transparent; border: 1px solid var(--line-2);
  border-radius: var(--radius); color: var(--paper); width: 42px; height: 38px;
  cursor: pointer; align-items: center; justify-content: center;
}
.nav__toggle svg { width: 20px; height: 20px; }
.nav__toggle .icon-close { display: none; }
.nav__toggle[aria-expanded="true"] .icon-open { display: none; }
.nav__toggle[aria-expanded="true"] .icon-close { display: block; }

/* ----------------------------------------------------------- buttons */
.btn {
  display: inline-flex; align-items: center; gap: .5rem;
  font-family: var(--font-body); font-weight: 700; font-size: var(--step--1);
  letter-spacing: .01em; line-height: 1; text-decoration: none; cursor: pointer;
  padding: .85rem 1.3rem; border-radius: var(--radius); border: 1px solid transparent;
  transition: transform .18s ease, background .18s ease, border-color .18s ease, box-shadow .18s ease;
  white-space: nowrap;
}
.btn--primary { background: var(--accent); color: var(--accent-ink); box-shadow: 0 10px 30px -14px rgba(255,106,61,0.8); }
.btn--primary:hover { background: var(--accent-2); transform: translateY(-2px); }
.btn--ghost { background: transparent; color: var(--paper); border-color: var(--line-2); }
.btn--ghost:hover { border-color: var(--line-3); background: rgba(176,206,238,0.06); }
.btn--text {
  padding: .5rem 0; color: var(--paper-soft); font-weight: 600;
  border-radius: 0; gap: .4rem;
}
.btn--text:hover { color: var(--accent-2); }

.link {
  color: var(--paper); text-decoration: none;
  background-image: linear-gradient(var(--accent), var(--accent));
  background-size: 100% 1px; background-repeat: no-repeat; background-position: 0 100%;
  padding-bottom: 1px; transition: color .18s ease, background-size .18s ease;
}
.link:hover { color: var(--accent-2); }

/* --------------------------------------------------- labels / titles */
.eyebrow, .annot, .measure {
  font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .18em;
  text-transform: uppercase; color: var(--accent-2);
}
.eyebrow { display: block; margin-bottom: 1rem; }
.annot { color: var(--paper-mute); }
/* measurement-style label with end ticks, like a technical drawing */
.measure {
  display: inline-flex; align-items: center; gap: .6rem; color: var(--paper-mute);
}
.measure::before, .measure::after {
  content: ""; height: 1px; width: clamp(18px, 5vw, 44px); background: var(--line-2);
}
.kicker {
  font-family: var(--font-mono); font-size: var(--step--1); color: var(--paper-mute);
  letter-spacing: .04em;
}

.section-title { font-size: var(--step-3); line-height: 1.06; max-width: 20ch; }
.section-title--xl { font-size: var(--step-4); max-width: 16ch; }
.lede { font-size: var(--step-1); line-height: 1.5; color: var(--paper-soft); max-width: 62ch; margin: 1.2rem 0 0; }
.accent { color: var(--accent); }

/* ------------------------------------------------------------- hero */
.hero { display: grid; gap: 1.6rem; }
.hero__title { font-size: var(--step-5); line-height: 1.0; display: grid; gap: .04em; max-width: 16ch; }
.hero__sub { font-size: var(--step-1); line-height: 1.5; color: var(--paper-soft); max-width: 56ch; }
.hero__actions { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem 1.4rem; margin-top: .6rem; }

/* ---------------------------------------------------- proof numbers */
.proofbar__grid {
  display: grid; grid-template-columns: repeat(4, 1fr);
  gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden;
}
.stat { background: var(--ground-2); padding: clamp(1.3rem, 2.5vw, 2rem); display: grid; gap: .7rem; align-content: start; }
.stat__num {
  font-family: var(--font-display); font-weight: 600; font-style: italic;
  font-size: clamp(2.4rem, 1.6rem + 3vw, 3.8rem); line-height: 1; color: var(--accent);
  letter-spacing: -.02em;
}
.stat__label { font-size: var(--step--1); line-height: 1.45; color: var(--paper-soft); max-width: 26ch; }

/* schematic number callout: huge number annotated like a drawing */
.callout { position: relative; padding-left: 1.4rem; }
.callout::before {
  content: ""; position: absolute; left: 0; top: .35em; bottom: .35em; width: 2px;
  background: linear-gradient(var(--accent), transparent);
}
.callout__num {
  font-family: var(--font-display); font-weight: 600; font-style: italic;
  font-size: clamp(3rem, 2rem + 6vw, 6.5rem); line-height: .95; color: var(--paper);
  letter-spacing: -.03em; display: block;
}
.callout__label { display: block; font-size: var(--step-0); color: var(--paper-soft); margin-top: .6rem; max-width: 30ch; }
.callout__src { display: block; font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .1em; text-transform: uppercase; color: var(--paper-mute); margin-top: .5rem; }

/* -------------------------------------------------------- problem */
.problem__inner { display: grid; gap: 1.2rem; max-width: 70ch; }

/* ---------------------------------------------------------- cards */
.card-grid { display: grid; gap: clamp(1rem, 2vw, 1.6rem); }
.card-grid--3 { grid-template-columns: repeat(3, 1fr); }
.card-grid--2 { grid-template-columns: repeat(2, 1fr); }

.card {
  background: var(--ground-2); border: 1px solid var(--line); border-radius: var(--radius);
  padding: clamp(1.4rem, 2.5vw, 2rem); position: relative;
  transition: transform .25s ease, border-color .25s ease, box-shadow .25s ease;
}
.card::before {
  content: ""; position: absolute; inset: 0 0 auto 0; height: 2px;
  background: linear-gradient(90deg, var(--accent), transparent);
}
a.card, .card--link { text-decoration: none; color: inherit; display: block; }
a.card:hover, .card--link:hover { transform: translateY(-3px); border-color: var(--line-2); box-shadow: 0 26px 50px -30px rgba(0,0,0,0.7); }

/* case card */
.case { display: grid; gap: .9rem; align-content: start; }
.case__context { font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .08em; text-transform: uppercase; color: var(--paper-mute); }
.case__did { color: var(--paper-soft); font-size: var(--step--1); line-height: 1.55; }
.case__metric { display: grid; gap: .15rem; margin-top: .3rem; }
.case__big { font-family: var(--font-display); font-weight: 600; font-style: italic; font-size: clamp(2.6rem, 1.8rem + 3vw, 4rem); line-height: 1; color: var(--accent); }
.case__unit { font-size: var(--step--1); color: var(--paper-soft); }
.case__sub { font-size: var(--step--2); color: var(--paper-mute); margin-top: .5rem; line-height: 1.5; }
.case__more { margin-top: .4rem; font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .08em; text-transform: uppercase; color: var(--accent-2); }

/* playbook card */
.pcard { display: grid; gap: .7rem; align-content: start; }
.pcard__tag { font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .12em; text-transform: uppercase; color: var(--paper-mute); }
.pcard__title { font-size: var(--step-1); color: var(--paper); }
.pcard__desc { font-size: var(--step--1); color: var(--paper-soft); line-height: 1.55; }
.pcard__more { font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .08em; text-transform: uppercase; color: var(--accent-2); margin-top: .2rem; }

/* ------------------------------------------------ schematic timeline */
.timeline { display: grid; gap: clamp(1rem, 2vw, 1.5rem); counter-reset: phase; }
.timeline--cols { grid-template-columns: repeat(3, 1fr); }
.phase {
  background: var(--ground-2); border: 1px solid var(--line); border-radius: var(--radius);
  padding: clamp(1.5rem, 2.5vw, 2.2rem); position: relative;
  display: grid; grid-template-columns: auto 1fr; gap: 0 1.3rem; align-items: start;
}
.phase::before { content: ""; position: absolute; inset: 0 0 auto 0; height: 2px; background: linear-gradient(90deg, var(--accent), var(--accent-2), transparent); }
.phase__index {
  font-family: var(--font-mono); font-weight: 600; font-size: 1rem; letter-spacing: .05em;
  color: var(--accent-ink); background: var(--accent);
  width: 2.4rem; height: 2.4rem; border-radius: 3px;
  display: inline-flex; align-items: center; justify-content: center; grid-row: 1 / span 3;
}
.phase__title { font-size: var(--step-2); grid-column: 2; }
.phase__weeks { grid-column: 2; font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .16em; text-transform: uppercase; color: var(--paper-mute); margin-top: .35rem; }
.phase__list { grid-column: 2; display: grid; gap: .7rem; margin-top: 1rem; }
.phase__list li { position: relative; padding-left: 1.3rem; font-size: var(--step--1); line-height: 1.5; color: var(--paper-soft); }
.phase__list li::before { content: ""; position: absolute; left: 0; top: .62em; width: .5rem; height: .5rem; border: 1px solid var(--accent); transform: rotate(45deg); }

/* ------------------------------------------------------- compare */
.versus { display: grid; gap: clamp(1rem, 2vw, 1.6rem); grid-template-columns: repeat(2, 1fr); margin-top: 2.2rem; }
.versus__col { background: var(--ground-2); border: 1px solid var(--line); border-radius: var(--radius); padding: clamp(1.4rem, 2.5vw, 2rem); }
.versus__col--operator { border-color: var(--line-2); background: linear-gradient(180deg, rgba(255,106,61,0.07), transparent), var(--ground-2); }
.versus__tag { font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .12em; text-transform: uppercase; color: var(--paper-mute); margin-bottom: 1rem; }
.versus__col--operator .versus__tag { color: var(--accent-2); }
.versus__col ul { display: grid; gap: .85rem; }
.versus__col li { position: relative; padding-left: 1.4rem; color: var(--paper-soft); font-size: var(--step--1); line-height: 1.5; }
.versus__col li::before { content: ""; position: absolute; left: 0; top: .6em; width: .5rem; height: .5rem; transform: rotate(45deg); border: 1px solid var(--line-3); }
.versus__col--operator li::before { background: var(--accent); border-color: var(--accent); }

/* for / not-for */
.fit { display: grid; gap: clamp(1rem, 2vw, 1.6rem); grid-template-columns: repeat(2, 1fr); }
.fit__col { background: var(--ground-2); border: 1px solid var(--line); border-radius: var(--radius); padding: clamp(1.4rem, 2.5vw, 2rem); }
.fit__col h3 { font-size: var(--step-1); margin-bottom: 1rem; }
.fit__col ul { display: grid; gap: .8rem; }
.fit__col li { position: relative; padding-left: 1.7rem; color: var(--paper-soft); font-size: var(--step--1); line-height: 1.5; }
.fit__col li::before { position: absolute; left: 0; top: 0; font-family: var(--font-mono); font-weight: 600; }
.fit__col--yes li::before { content: "+"; color: var(--accent-2); }
.fit__col--no li::before { content: "\2013"; color: var(--paper-mute); }

/* --------------------------------------------------------- prose */
.prose { max-width: 70ch; }
.prose > * + * { margin-top: 1.15rem; }
.prose h2 { font-size: var(--step-2); margin-top: 2.6rem; line-height: 1.12; }
.prose h3 { font-size: var(--step-1); margin-top: 2rem; color: var(--paper); }
.prose p, .prose li { color: var(--paper-soft); }
.prose strong { color: var(--paper); font-weight: 700; }
.prose a { color: var(--paper); text-decoration: underline; text-decoration-color: var(--accent); text-underline-offset: 3px; }
.prose ul, .prose ol { display: grid; gap: .7rem; padding-left: 1.4rem; }
.prose ul { list-style: none; padding-left: 0; }
.prose ul > li { position: relative; padding-left: 1.4rem; }
.prose ul > li::before { content: ""; position: absolute; left: 0; top: .62em; width: .5rem; height: .5rem; border: 1px solid var(--accent); transform: rotate(45deg); }
.prose ol { list-style: decimal; padding-left: 1.4rem; }
.prose ol > li::marker { color: var(--accent-2); font-family: var(--font-mono); }
.prose blockquote {
  margin: 1.6rem 0; padding: 1rem 1.4rem; border-left: 2px solid var(--accent);
  background: var(--ground-2); border-radius: 0 var(--radius) var(--radius) 0;
  font-family: var(--font-display); font-style: italic; font-size: var(--step-1); color: var(--paper);
}
.prose figure { margin: 2rem 0; }
.prose figcaption { font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .04em; color: var(--paper-mute); margin-top: .6rem; text-align: center; }
/* schematic diagram box for use inside prose */
.diagram { border: 1px solid var(--line-2); border-radius: var(--radius); background: var(--ground-2); padding: clamp(1.2rem, 3vw, 2rem); }
.diagram__row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: 3px; overflow: hidden; }
.diagram__cell { background: var(--ground-3); padding: 1rem; text-align: center; }
.diagram__cell .annot { display: block; margin-bottom: .4rem; }
.diagram__cell strong { display: block; font-family: var(--font-display); font-size: var(--step-0); color: var(--paper); }

/* layout helper: content + sticky aside */
.layout-aside { display: grid; grid-template-columns: minmax(0, 1fr) 280px; gap: clamp(2rem, 5vw, 4rem); align-items: start; }
.aside-sticky { position: sticky; top: calc(var(--header-h) + 24px); display: grid; gap: 1.2rem; }
.aside-card { background: var(--ground-2); border: 1px solid var(--line-2); border-radius: var(--radius); padding: 1.5rem; display: grid; gap: 1rem; }
.aside-card p { font-size: var(--step--1); color: var(--paper-soft); margin: 0; }

/* ----------------------------------------------------- breadcrumb */
.breadcrumb { font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .06em; color: var(--paper-mute); display: flex; flex-wrap: wrap; gap: .5rem; align-items: center; }
.breadcrumb a { color: var(--paper-mute); text-decoration: none; }
.breadcrumb a:hover { color: var(--paper-soft); }
.breadcrumb span[aria-current] { color: var(--paper-soft); }
.breadcrumb .sep { color: var(--line-3); }

/* ------------------------------------------------------- accordion */
.faq__list { display: grid; gap: .8rem; max-width: 80ch; }
.faq__item { background: var(--ground-2); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.faq__item summary {
  cursor: pointer; list-style: none; padding: 1.1rem 1.3rem; font-family: var(--font-display);
  font-weight: 600; font-size: var(--step-1); color: var(--paper);
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
}
.faq__item summary::-webkit-details-marker { display: none; }
.faq__item summary::after { content: "+"; font-family: var(--font-mono); color: var(--accent-2); font-size: 1.4rem; transition: transform .2s ease; }
.faq__item[open] summary::after { content: "\2013"; }
.faq__item[open] summary { border-bottom: 1px solid var(--line); }
.faq__answer { padding: 1.1rem 1.3rem 1.3rem; }
.faq__answer p { margin: 0; color: var(--paper-soft); }

/* ----------------------------------------------------------- about */
.about { display: grid; grid-template-columns: 280px 1fr; gap: clamp(1.5rem, 4vw, 3.5rem); align-items: start; }
.about__photo { border: 1px solid var(--line-2); border-radius: var(--radius); overflow: hidden; background: var(--ground-2); }
.about__photo img { width: 100%; height: auto; display: block; }
.about__text { display: grid; gap: 1rem; max-width: 60ch; }
.about__text p { margin: 0; color: var(--paper-soft); }

/* --------------------------------------------------------- email capture */
.capture { background: var(--ground-2); border: 1px solid var(--line-2); border-radius: var(--radius); padding: clamp(1.5rem, 3vw, 2.4rem); display: grid; gap: 1rem; max-width: 60ch; }
.capture__row { display: flex; flex-wrap: wrap; gap: .8rem; }
.capture input[type="email"] {
  flex: 1 1 240px; background: var(--ground); border: 1px solid var(--line-2);
  border-radius: var(--radius); color: var(--paper); padding: .85rem 1rem; font: inherit; font-size: var(--step--1);
}
.capture input::placeholder { color: var(--paper-mute); }

/* ------------------------------------------------------- final CTA */
.final-cta { display: grid; gap: 1.2rem; justify-items: start; }
.final-cta__title { font-size: var(--step-4); max-width: 18ch; }
.final-cta__email { font-size: var(--step--1); color: var(--paper-mute); }

/* ---------------------------------------------------------- footer */
.site-footer { border-top: 1px solid var(--line-2); padding-block: clamp(2.5rem, 5vw, 4rem); display: grid; gap: 1rem; }
.site-footer__name { font-family: var(--font-display); font-weight: 600; font-size: 1.2rem; margin: 0; }
.site-footer__links { display: flex; flex-wrap: wrap; gap: 1.2rem 1.8rem; align-items: center; }
.site-footer__links a { font-size: var(--step--1); color: var(--paper-soft); text-decoration: none; }
.site-footer__links a:hover { color: var(--paper); }
.site-footer__fine { font-family: var(--font-mono); font-size: var(--step--2); letter-spacing: .04em; color: var(--paper-mute); margin: 0; }

/* ----------------------------------------------------- blueprint line */
.blueprint-line path, .blueprint-line line, .blueprint-line polyline { stroke: var(--line-3); stroke-width: 1.4; fill: none; }
.blueprint-line .accent-stroke { stroke: var(--accent); }

/* --------------------------------------------------------- motion */
[data-reveal] { opacity: 0; transform: translateY(16px); }
[data-reveal].is-in {
  opacity: 1; transform: none;
  transition: opacity .6s ease var(--reveal-delay, 0ms), transform .6s cubic-bezier(.2,.7,.2,1) var(--reveal-delay, 0ms);
}
.js [data-reveal] { will-change: opacity, transform; }
/* without JS, everything is visible */
html:not(.js) [data-reveal] { opacity: 1; transform: none; }

/* draw-on animation for blueprint svg strokes */
.blueprint-line.draw path, .blueprint-line.draw polyline, .blueprint-line.draw line {
  stroke-dasharray: var(--len, 800); stroke-dashoffset: var(--len, 800);
}
.blueprint-line.draw.is-in path, .blueprint-line.draw.is-in polyline, .blueprint-line.draw.is-in line {
  transition: stroke-dashoffset 1.4s ease; stroke-dashoffset: 0;
}

/* =============================================================== responsive */
@media (max-width: 940px) {
  .layout-aside { grid-template-columns: 1fr; }
  .aside-sticky { position: static; }
  .proofbar__grid { grid-template-columns: repeat(2, 1fr); }
  .card-grid--3 { grid-template-columns: repeat(2, 1fr); }
  .timeline--cols { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  :root { --header-h: 64px; }
  .nav__toggle { display: inline-flex; }
  .nav__links {
    position: fixed; inset: var(--header-h) 0 auto 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--ground-2); border-bottom: 1px solid var(--line-2);
    padding: .5rem var(--gutter) 1.2rem;
    transform: translateY(-12px); opacity: 0; pointer-events: none;
    transition: opacity .2s ease, transform .2s ease;
  }
  .nav__links.is-open { transform: none; opacity: 1; pointer-events: auto; }
  .nav__links a { padding: .9rem 0; border-bottom: 1px solid var(--line); font-size: var(--step-0); }
  .nav__cta { margin: .9rem 0 0; justify-content: center; }
  .versus, .fit, .card-grid--2, .card-grid--3 { grid-template-columns: 1fr; }
  .about { grid-template-columns: 1fr; }
  .about__photo { max-width: 240px; }
  .diagram__row { grid-template-columns: 1fr; }
}
@media (max-width: 460px) {
  .proofbar__grid { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  [data-reveal], [data-reveal].is-in { opacity: 1 !important; transform: none !important; transition: none !important; }
  .blueprint-line.draw path, .blueprint-line.draw polyline, .blueprint-line.draw line { stroke-dashoffset: 0 !important; transition: none !important; }
  .btn:hover, a.card:hover, .card--link:hover { transform: none !important; }
}