/* =========================================================
   Side B Studio — design system
   Light-only by design. One accent. Two typefaces. Lots of air.
   ========================================================= */

:root {
  /* Surfaces — white base, cream for alternating bands.
     The cream is the logo's paper colour. */
  --paper:        #FFFFFF;
  --paper-sunk:   #F4EFE6;
  --card:         #FFFFFF;

  /* Ink — the record black */
  --ink:          #171512;
  --ink-soft:     #4A443C;
  --ink-faint:    #6E675C;

  /* Rules */
  --rule:         #E0D9CB;
  --rule-strong:  #C9C0AE;

  /* Accent — the vermillion record label.
     --accent is the brand graphic colour (3.6:1 — marks and rules only).
     --accent-ink is the accessible text/button shade (5.5:1 on paper,
     6.3:1 white-on-fill). Never set small text in --accent. */
  --accent:       #E3441F;
  --accent-ink:   #B32E10;
  --accent-deep:  #8F240C;
  --accent-wash:  #F7E9E2;

  /* Type */
  --font-display: "Fraunces", "Iowan Old Style", Georgia, "Times New Roman", serif;
  --font-body:    "Inter", system-ui, -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;

  /* Layout */
  --measure:      62ch;
  --measure-wide: 22ch;
  --shell:        1120px;
  --radius:       6px;
}

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

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-synthesis-weight: none;
}

img { max-width: 100%; display: block; }

::selection { background: rgba(227, 68, 31, 0.16); }

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

.skip-link {
  position: absolute; left: -9999px; top: 0;
  background: var(--ink); color: var(--paper);
  padding: 10px 16px; z-index: 100; border-radius: 0 0 var(--radius) 0;
}
.skip-link:focus { left: 0; }

/* ---------- Typography scale ---------- */

h1, h2, h3, h4 { margin: 0; font-weight: 600; }

.type-display {
  font-family: var(--font-display);
  font-size: 38px;
  font-weight: 600;
  line-height: 1.06;
  letter-spacing: -0.025em;
  font-variation-settings: "SOFT" 0, "WONK" 0, "opsz" 40;
}
.type-section {
  font-family: var(--font-display);
  font-size: 26px;
  font-weight: 600;
  line-height: 1.18;
  letter-spacing: -0.015em;
  font-variation-settings: "SOFT" 0, "WONK" 0, "opsz" 28;
}
.type-lede   { font-size: 18.5px; line-height: 1.6; color: var(--ink-soft); }
.type-body   { font-size: 15.5px; line-height: 1.7; color: var(--ink-soft); }
.type-subhead{ font-size: 16.5px; font-weight: 650; color: var(--ink); line-height: 1.4; }
.type-meta {
  font-size: 12px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.16em;
  color: var(--ink-faint);
}
.type-index {
  font-size: 13px; font-weight: 600; letter-spacing: 0.08em;
  color: var(--accent-ink);
  font-variant-numeric: tabular-nums lining-nums;
}

@media (min-width: 640px) {
  .type-display { font-size: 46px; }
  .type-section { font-size: 30px; }
  .type-lede    { font-size: 20.5px; }
  .type-body    { font-size: 16.5px; }
  .type-subhead { font-size: 17.5px; }
}
@media (min-width: 1024px) {
  .type-display { font-size: 56px; }
}

.measure      { max-width: var(--measure); }
.measure-wide { max-width: 18ch; }
.measure-mid  { max-width: 46ch; }

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

/* Signature accent rule */
.sig-rule {
  display: inline-block;
  width: 36px; height: 3px;
  border-radius: 999px;
  background: var(--accent);
}

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

.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: 20px;
}
@media (min-width: 640px) { .shell { padding-inline: 32px; } }
@media (min-width: 1024px){ .shell { padding-inline: 44px; } }

.section       { padding-block: 64px; }
.section--tight{ padding-block: 48px; }
.section--lead { padding-block: 72px 64px; }
.section--sunk { background: var(--paper-sunk); }
.section--edge { border-top: 1px solid var(--rule); }
@media (min-width: 640px) {
  .section       { padding-block: 88px; }
  .section--tight{ padding-block: 60px; }
  .section--lead { padding-block: 104px 88px; }
}

.section-head { margin-bottom: 40px; }
.section-head .type-meta { display: block; margin-bottom: 14px; }
.section-head .type-lede { margin-top: 18px; }

/* ---------- Header ---------- */

.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: saturate(180%) blur(10px);
  -webkit-backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease;
}
.site-header.is-stuck { border-bottom-color: var(--rule); }

.site-header__inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px; min-height: 68px;
}

.brand {
  display: inline-flex; align-items: center; gap: 10px;
  color: var(--ink); text-decoration: none;
  font-family: var(--font-display);
  font-size: 19px; font-weight: 600; letter-spacing: -0.01em;
}
.brand:hover { color: var(--ink); }
.brand__mark { width: 26px; height: 26px; flex: none; display: block; }
.brand:hover .brand__mark { transform: rotate(30deg); }
.brand__mark { transition: transform 0.5s cubic-bezier(0.2, 0.6, 0.2, 1); }
@media (prefers-reduced-motion: reduce) {
  .brand__mark, .brand:hover .brand__mark { transition: none; transform: none; }
}
.brand__sub {
  font-family: var(--font-body);
  font-size: 12px; font-weight: 600; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--ink-faint);
  padding-left: 10px; margin-left: 2px;
  border-left: 1px solid var(--rule-strong);
}
@media (max-width: 520px) { .brand__sub { display: none; } }

.nav { display: none; align-items: center; gap: 30px; }
@media (min-width: 900px) { .nav { display: flex; } }

.nav a {
  color: var(--ink-soft); text-decoration: none;
  font-size: 14.5px; font-weight: 500;
  transition: color 0.15s ease;
}
.nav a:hover, .nav a[aria-current="page"] { color: var(--ink); }
.nav a[aria-current="page"] { font-weight: 600; }

/* `.nav a` (0-1-1) outranks `.btn--primary` (0-1-0), so the CTA in the nav
   needs its own rule or it inherits the muted link colour. */
.nav a.btn--primary,
.nav a.btn--primary:hover { color: #fff; font-weight: 600; }

.nav-toggle {
  display: inline-flex; align-items: center; gap: 8px;
  background: none; border: 1px solid var(--rule-strong);
  border-radius: var(--radius); padding: 8px 12px;
  font: inherit; font-size: 13.5px; font-weight: 600;
  color: var(--ink); cursor: pointer;
}
@media (min-width: 900px) { .nav-toggle { display: none; } }

.nav-drawer {
  display: none;
  border-top: 1px solid var(--rule);
  background: var(--paper);
  padding: 8px 0 20px;
}
.nav-drawer.is-open { display: block; }
@media (min-width: 900px) { .nav-drawer { display: none !important; } }
.nav-drawer a {
  display: block; padding: 12px 0;
  border-bottom: 1px solid var(--rule);
  color: var(--ink); text-decoration: none; font-size: 16px; font-weight: 500;
}
.nav-drawer .btn { margin-top: 18px; width: 100%; border-bottom: 0; }
.nav-drawer a.btn--primary,
.nav-drawer a.btn--primary:hover { color: #fff; font-weight: 600; }

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 11px 20px;
  border-radius: var(--radius);
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-size: 14.5px; font-weight: 600; line-height: 1.2;
  text-decoration: none; cursor: pointer;
  transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}
.btn--primary { background: var(--accent-ink); color: #fff; }
.btn--primary:hover { background: var(--accent-deep); color: #fff; }
.btn--ghost { border-color: var(--rule-strong); color: var(--ink); background: transparent; }
.btn--ghost:hover { background: var(--card); color: var(--ink); border-color: var(--ink-faint); }
.btn--lg { padding: 14px 24px; font-size: 15.5px; }
.btn__arrow { transition: transform 0.15s ease; }
.btn:hover .btn__arrow { transform: translateX(2px); }

.link-quiet {
  font-size: 15px; font-weight: 600;
  color: var(--accent-ink); text-decoration: none;
}
.link-quiet:hover { text-decoration: underline; }

/* ---------- Hero ---------- */

/* Full-bleed split: photograph on the left, text on the right, together
   filling the viewport below the header. Stacks on narrow screens. */
.hero-split { display: grid; grid-template-columns: 1fr; }
@media (min-width: 900px) {
  .hero-split {
    grid-template-columns: 1fr 1fr;
    min-height: calc(100vh - 68px);
    min-height: calc(100svh - 68px);
  }
}

.hero-split__media {
  position: relative; overflow: hidden;
  background: var(--paper-sunk);
}
.hero-split__media img {
  width: 100%; height: 100%;
  min-height: 48vh;
  object-fit: cover; object-position: center;
}
@media (min-width: 900px) { .hero-split__media img { min-height: 0; } }
/* Warm base wash, tying the photograph to the record-label accent. */
.hero-split__media::after {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background: linear-gradient(to top,
    rgba(168, 45, 16, 0.20) 0%,
    rgba(168, 45, 16, 0.04) 44%,
    transparent 100%);
}

.hero-split__body {
  display: flex; align-items: center;
  padding: 52px 20px 60px;
}
@media (min-width: 640px) { .hero-split__body { padding: 68px 32px 76px; } }
@media (min-width: 900px) {
  .hero-split__body {
    justify-content: center;
    padding-block: 72px;
    /* Balanced gutters. Aligning the right edge to the nav left a very wide
       right-hand gap on large screens; centring in the column reads better. */
    padding-inline: clamp(40px, 5vw, 72px);
  }
}

.hero-split__inner { width: 100%; max-width: 34rem; }

.hero__eyebrow { display: flex; align-items: center; gap: 12px; margin-bottom: 26px; flex-wrap: wrap; }
.hero-split .type-lede { margin-top: 26px; }

.hero__actions {
  display: flex; flex-direction: column; gap: 12px;
  margin-top: 34px;
}
@media (min-width: 560px) { .hero__actions { flex-direction: row; align-items: center; } }

.checklist {
  list-style: none; margin: 38px 0 0; padding: 26px 0 0;
  border-top: 1px solid var(--rule);
  display: grid; gap: 10px;
}
.checklist li {
  display: flex; align-items: flex-start; gap: 10px;
  font-size: 13.5px; line-height: 1.55; color: var(--ink-soft);
}
.checklist svg { flex: none; margin-top: 3px; color: var(--accent); }

/* Hero side panel — a "record sleeve" of what an engagement produces */
.sleeve {
  display: none;
  background: var(--card);
  border: 1px solid var(--rule);
  border-radius: 2px;
  padding: 28px;
}
@media (min-width: 1024px) { .sleeve { display: block; } }
.sleeve__label {
  display: flex; align-items: center; justify-content: space-between;
  padding-bottom: 14px; margin-bottom: 20px;
  border-bottom: 1px solid var(--rule);
}
.sleeve__rows { list-style: none; margin: 0; padding: 0; }
.sleeve__rows li {
  display: flex; align-items: baseline; gap: 12px;
  padding: 13px 0;
  border-bottom: 1px solid var(--rule);
  font-size: 14px; color: var(--ink);
}
.sleeve__rows li:last-child { border-bottom: 0; padding-bottom: 0; }
.sleeve__rows .n {
  font-variant-numeric: tabular-nums;
  font-size: 12px; font-weight: 700; color: var(--accent-ink);
  flex: none; width: 20px;
}
.sleeve__foot {
  margin: 20px 0 0; padding-top: 16px;
  border-top: 1px solid var(--rule);
  font-size: 12.5px; line-height: 1.55; color: var(--ink-faint);
}

/* Same panel, used full-width outside the hero (the base .sleeve is hidden
   below 1024px because it only ever sat in the hero's second column). */
.sleeve--wide { display: block; }
@media (min-width: 768px) {
  .sleeve--wide { padding: 32px 34px; }
  .sleeve--wide .sleeve__rows {
    display: grid; grid-template-columns: 1fr 1fr; column-gap: 40px;
  }
  .sleeve--wide .sleeve__rows li:nth-last-child(-n+2) { border-bottom: 0; }
  .sleeve--wide .sleeve__rows li:last-child { padding-bottom: 13px; }
  .sleeve--wide .sleeve__foot { max-width: 62ch; }
}

/* ---------- Grids & cards ---------- */

.grid { display: grid; gap: 24px; }
.grid--2 { grid-template-columns: 1fr; }
.grid--3 { grid-template-columns: 1fr; }
.grid--4 { grid-template-columns: 1fr; }
@media (min-width: 640px) {
  .grid--2 { grid-template-columns: repeat(2, 1fr); }
  .grid--4 { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
  .grid--3 { grid-template-columns: repeat(3, 1fr); }
  .grid--4 { grid-template-columns: repeat(4, 1fr); }
}

.card {
  background: var(--card);
  border: 1px solid var(--rule);
  border-radius: 2px;
  padding: 28px 26px;
  display: flex; flex-direction: column;
  transition: border-color 0.18s ease;
}
.card:hover { border-color: var(--rule-strong); }
.card__label { display: block; margin-bottom: 16px; }
.card .type-subhead { margin-bottom: 12px; }
.card .type-body { margin: 0; }

.deliverables {
  list-style: none; margin: 20px 0 0; padding: 18px 0 0;
  border-top: 1px solid var(--rule);
  display: grid; gap: 9px;
}
.deliverables li {
  position: relative; padding-left: 18px;
  font-size: 13.5px; line-height: 1.5; color: var(--ink-soft);
}
.deliverables li::before {
  content: ""; position: absolute; left: 0; top: 8px;
  width: 5px; height: 5px; border-radius: 999px; background: var(--accent);
}

.card__foot {
  margin-top: auto; padding-top: 18px;
  font-size: 12.5px; line-height: 1.5; color: var(--ink-faint);
}
/* Sits below the "Best for" line, which carries the margin-top:auto that
   pins both to the bottom of the card. */
.card__cta { align-self: flex-start; margin-top: 18px; }

.card__foot strong {
  display: block; margin-bottom: 3px;
  font-size: 11px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.14em; color: var(--ink-faint);
}

/* ---------- Pain list ---------- */

.pains { list-style: none; margin: 0; padding: 0; display: grid; gap: 0; }
@media (min-width: 768px) { .pains { grid-template-columns: 1fr 1fr; column-gap: 44px; } }
.pains li {
  display: flex; gap: 14px; align-items: flex-start;
  padding: 18px 0;
  border-top: 1px solid var(--rule);
  font-size: 15.5px; line-height: 1.6; color: var(--ink-soft);
}
.pains li::before {
  content: ""; flex: none; margin-top: 10px;
  width: 14px; height: 1px; background: var(--rule-strong);
}

/* ---------- Steps ---------- */

.steps { display: grid; gap: 0; }
@media (min-width: 768px) { .steps { grid-template-columns: repeat(3, 1fr); } }
.step { padding: 26px 0; border-top: 1px solid var(--rule); }
@media (min-width: 768px) {
  .step { padding: 0 0 0 30px; border-top: 0; border-left: 1px solid var(--rule); }
  .step:first-child { padding-left: 0; border-left: 0; }
}
.step .type-index { display: block; margin-bottom: 14px; }
.step .type-subhead { margin-bottom: 10px; }

/* ---------- Stats ---------- */

.stats { display: grid; gap: 0; }
@media (min-width: 640px) { .stats { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 900px) { .stats { grid-template-columns: repeat(4, 1fr); } }
.stat { padding: 22px 0; border-top: 1px solid var(--rule); }
@media (min-width: 900px) {
  .stat { padding: 0 0 0 28px; border-top: 0; border-left: 1px solid var(--rule); }
  .stat:first-child { padding-left: 0; border-left: 0; }
}
.stat__num {
  font-family: var(--font-display);
  font-size: 32px; font-weight: 600; line-height: 1.1;
  letter-spacing: -0.02em; color: var(--ink);
  font-variant-numeric: lining-nums;
}
.stat__cap { margin-top: 8px; font-size: 13.5px; line-height: 1.5; color: var(--ink-faint); }

/* ---------- Pricing ---------- */

.price-card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--rule);
  border-radius: 2px;
  padding: 30px 28px;
  display: flex; flex-direction: column;
}
.price-card--feature { border-color: var(--accent); }
/* Pulled out of flow so the three tier names — and therefore the three
   prices — sit on the same baseline whether or not a card is flagged. */
.price-card__flag {
  position: absolute; top: 26px; right: 26px;
  padding: 4px 9px;
  background: var(--accent-wash); color: var(--accent-deep);
  border-radius: 3px;
  font-size: 10.5px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.14em;
}
.price-card__amount {
  display: flex; align-items: baseline; gap: 6px;
  margin: 16px 0 6px;
  font-family: var(--font-display);
  font-size: 34px; font-weight: 600; letter-spacing: -0.02em;
  color: var(--ink);
  font-variant-numeric: lining-nums;
}
.price-card__amount .per {
  font-family: var(--font-body);
  font-size: 14px; font-weight: 500; letter-spacing: 0;
  color: var(--ink-faint);
}
.price-card__note { font-size: 13px; color: var(--ink-faint); margin: 0 0 4px; }

/* ---------- Catalog ---------- */

.catalog { display: grid; gap: 0; }
@media (min-width: 768px) { .catalog { grid-template-columns: 1fr 1fr; column-gap: 44px; } }
.catalog__item { padding: 22px 0; border-top: 1px solid var(--rule); }
.catalog__item .type-subhead { margin-bottom: 8px; }
.catalog__item p { margin: 0; }

/* ---------- Callout / band ---------- */

.band {
  background: var(--ink); color: var(--paper);
  border-radius: 2px;
  padding: 44px 32px;
}
@media (min-width: 768px) { .band { padding: 56px 52px; } }
.band .type-section { color: var(--paper); }
.band p { color: rgba(250, 248, 244, 0.72); }
.band .btn--primary { background: var(--paper); color: var(--ink); }
.band .btn--primary:hover { background: #fff; color: var(--ink); }
.band .sig-rule { background: var(--paper); }

.note {
  border-left: 2px solid var(--accent);
  padding: 4px 0 4px 20px;
  margin: 0;
}

/* ---------- Prose (about page) ---------- */

.prose p { margin: 0 0 20px; font-size: 16.5px; line-height: 1.72; color: var(--ink-soft); }
.prose p:last-child { margin-bottom: 0; }
.prose strong { color: var(--ink); font-weight: 650; }
.prose h3 { margin: 36px 0 14px; }

/* ---------- Form ---------- */

.form { display: grid; gap: 20px; }
.field { display: grid; gap: 7px; }
.field label { font-size: 13.5px; font-weight: 600; color: var(--ink); }
.field label .opt { font-weight: 500; color: var(--ink-faint); }
.field input, .field select, .field textarea {
  width: 100%;
  padding: 11px 13px;
  background: var(--card);
  border: 1px solid var(--rule-strong);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: 15.5px; color: var(--ink);
}
.field textarea { min-height: 140px; resize: vertical; }
.field input:focus, .field select:focus, .field textarea:focus {
  outline: 2px solid var(--accent-ink); outline-offset: 1px; border-color: var(--accent-ink);
}
.field__hint { font-size: 12.5px; color: var(--ink-faint); }
.form__row { display: grid; gap: 20px; }
@media (min-width: 640px) { .form__row { grid-template-columns: 1fr 1fr; } }
.hp { position: absolute; left: -9999px; opacity: 0; height: 0; width: 0; }

.form-status { font-size: 14px; margin: 0; }
.form-status[data-state="error"] { color: #A3220E; }
.form-status[data-state="ok"] { color: #1E5B34; }

.form-success {
  border: 1px solid var(--accent);
  border-radius: 2px;
  background: var(--accent-wash);
  padding: 28px;
}

/* ---------- Footer ---------- */

.site-footer {
  border-top: 1px solid var(--rule);
  background: var(--card);
  margin-top: auto;
  padding-block: 48px 32px;
}
.site-footer__grid { display: grid; gap: 36px; }
@media (min-width: 768px) { .site-footer__grid { grid-template-columns: 2fr 1fr; gap: 48px; } }
.site-footer h4 { margin-bottom: 14px; }
.site-footer ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.site-footer ul a { color: var(--ink-soft); text-decoration: none; font-size: 14px; }
.site-footer ul a:hover { color: var(--ink); }
.site-footer__fine {
  margin-top: 40px; padding-top: 22px;
  border-top: 1px solid var(--rule);
  display: flex; flex-wrap: wrap; gap: 12px; justify-content: space-between;
  font-size: 12.5px; color: var(--ink-faint);
}

/* ---------- Page head (interior pages) ---------- */

.page-head { padding-block: 56px 44px; }
@media (min-width: 640px) { .page-head { padding-block: 80px 60px; } }
.page-head .type-meta { display: block; margin-bottom: 16px; }
.page-head .type-lede { margin-top: 22px; }

/* ---------- Reveal ---------- */

/* Gated on `.js`, set by an inline script in <head>. Without JavaScript —
   or if site.js fails to load — the content is simply visible, rather than
   a page of invisible text. */
.js .reveal { opacity: 0; transform: translateY(14px); }
.js .reveal.is-in {
  opacity: 1; transform: none;
  transition: opacity 0.6s cubic-bezier(0.2, 0.6, 0.2, 1), transform 0.6s cubic-bezier(0.2, 0.6, 0.2, 1);
}
@media (prefers-reduced-motion: reduce) {
  .js .reveal { opacity: 1; transform: none; }
  .js .reveal.is-in { transition: none; }
}

/* ---------- Portrait (about page) ---------- */

.portrait {
  position: relative;
  border: 1px solid var(--rule);
  background: var(--card);
  padding: 10px;
  border-radius: 2px;
  max-width: 380px;
}
.portrait img { width: 100%; height: auto; border-radius: 1px; }
.portrait figcaption {
  display: flex; align-items: baseline; justify-content: space-between; gap: 12px;
  padding: 14px 4px 4px;
  font-size: 12.5px; color: var(--ink-faint);
}

/* ---------- Proof / data ---------- */

.proof { display: grid; gap: 0; }
@media (min-width: 768px) { .proof { grid-template-columns: repeat(3, 1fr); } }
.proof__item { padding: 26px 0; border-top: 1px solid var(--rule); }
@media (min-width: 768px) {
  .proof__item { padding: 0 26px 0 0; border-top: 0; border-right: 1px solid var(--rule); }
  .proof__item:last-child { border-right: 0; padding-right: 0; }
  .proof__item + .proof__item { padding-left: 26px; }
}
.proof__num {
  font-family: var(--font-display);
  font-size: 46px; font-weight: 600; line-height: 1;
  letter-spacing: -0.03em; color: var(--ink);
  font-variant-numeric: lining-nums;
}
.proof__num .unit { font-size: 26px; color: var(--accent-ink); }
.proof__claim {
  margin: 14px 0 0;
  font-size: 15.5px; line-height: 1.55; color: var(--ink);
  font-weight: 500;
}
.proof__src {
  margin: 12px 0 0;
  font-size: 12.5px; line-height: 1.5; color: var(--ink-faint);
}
.proof__src a { color: var(--ink-faint); text-decoration: underline; }
.proof__src a:hover { color: var(--accent-ink); }

.figure-note {
  margin: 36px 0 0; padding-top: 20px;
  border-top: 1px solid var(--rule);
  font-size: 13px; line-height: 1.6; color: var(--ink-faint);
  max-width: 76ch;
}

/* ---------- Utilities ---------- */

.mt-0 { margin-top: 0; }
.mt-s { margin-top: 14px; }
.mt-m { margin-top: 24px; }
.mt-l { margin-top: 40px; }
.mt-xl{ margin-top: 56px; }
.center { text-align: center; }
.stack-page { min-height: 100vh; display: flex; flex-direction: column; }
.stack-page main { flex: 1; }