/* =========================================================================
   prashanthshenoy.com design system
   Mobile-first. Light default, dark via prefers-color-scheme + [data-theme].
   ========================================================================= */

/* ---------- 1. Tokens ---------------------------------------------------- */

:root {
  /* Colour: warm paper, near-black ink, one deep teal accent */
  --paper:        #FBFAF7;
  --paper-2:      #F3F1EC;
  --paper-3:      #E9E6DF;
  --ink:          #16181C;
  --ink-2:        #3D424B;
  --ink-3:        #6B7280;
  --rule:         #DCD8D0;
  --rule-strong:  #C3BDB2;
  --accent:       #0E5E56;
  --accent-hover: #0A4740;
  --accent-wash:  #E4EEEC;
  --focus:        #0E5E56;

  /* Type */
  --font-display: "Newsreader", Georgia, "Times New Roman", serif;
  --font-body:    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono:    ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  /* Fluid scale */
  --step--2: clamp(0.72rem, 0.70rem + 0.10vw, 0.78rem);
  --step--1: clamp(0.84rem, 0.81rem + 0.15vw, 0.92rem);
  --step-0:  clamp(1.00rem, 0.97rem + 0.18vw, 1.10rem);
  --step-1:  clamp(1.20rem, 1.13rem + 0.35vw, 1.42rem);
  --step-2:  clamp(1.44rem, 1.31rem + 0.65vw, 1.85rem);
  --step-3:  clamp(1.75rem, 1.50rem + 1.20vw, 2.60rem);
  --step-4:  clamp(2.10rem, 1.62rem + 2.30vw, 3.70rem);

  /* Space */
  --sp-1: 0.375rem;
  --sp-2: 0.75rem;
  --sp-3: 1.125rem;
  --sp-4: 1.75rem;
  --sp-5: 2.75rem;
  --sp-6: 4rem;
  --sp-7: 6rem;

  --measure: 34rem;
  --wrap: 68rem;
  --radius: 3px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper:        #101216;
    --paper-2:      #171A1F;
    --paper-3:      #1F242B;
    --ink:          #ECEAE5;
    --ink-2:        #B4B9C1;
    --ink-3:        #868D97;
    --rule:         #2A2F37;
    --rule-strong:  #3B424C;
    --accent:       #6FC5B6;
    --accent-hover: #92D6C9;
    --accent-wash:  #16302C;
    --focus:        #6FC5B6;
  }
}

:root[data-theme="dark"] {
  --paper:        #101216;
  --paper-2:      #171A1F;
  --paper-3:      #1F242B;
  --ink:          #ECEAE5;
  --ink-2:        #B4B9C1;
  --ink-3:        #868D97;
  --rule:         #2A2F37;
  --rule-strong:  #3B424C;
  --accent:       #6FC5B6;
  --accent-hover: #92D6C9;
  --accent-wash:  #16302C;
  --focus:        #6FC5B6;
}

/* ---------- 2. Reset ----------------------------------------------------- */

*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

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

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

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

/* ---------- 3. Typography ------------------------------------------------ */

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.14;
  letter-spacing: -0.015em;
  text-wrap: balance;
}

h1 { font-size: var(--step-4); }
h2 { font-size: var(--step-3); }
h3 { font-size: var(--step-1); line-height: 1.25; }

p { text-wrap: pretty; }
p + p { margin-top: var(--sp-3); }

a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
  text-decoration-color: color-mix(in srgb, var(--accent) 40%, transparent);
  transition: color .15s ease, text-decoration-color .15s ease;
}
a:hover { color: var(--accent-hover); text-decoration-color: currentColor; }

strong { font-weight: 600; }

/* Eyebrow: the quiet scaffolding label */
.eyebrow {
  font-size: var(--step--2);
  font-weight: 600;
  letter-spacing: 0.11em;
  text-transform: uppercase;
  color: var(--ink-3);
  font-family: var(--font-body);
}

.lede {
  font-size: var(--step-1);
  line-height: 1.5;
  color: var(--ink-2);
  font-family: var(--font-display);
}

.muted { color: var(--ink-3); }

.num {
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum" 1;
}

/* ---------- 4. Layout ---------------------------------------------------- */

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 5vw, 3rem);
}

.wrap--narrow { max-width: 46rem; }

section { padding-block: var(--sp-6); }
@media (min-width: 48rem) { section { padding-block: var(--sp-7); } }

.rule-top { border-top: 1px solid var(--rule); }

.section-head {
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
  margin-bottom: var(--sp-5);
  max-width: 46rem;
}
.section-head p { color: var(--ink-2); max-width: var(--measure); }

/* ---------- 5. Header ---------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: saturate(150%) blur(10px);
  -webkit-backdrop-filter: saturate(150%) blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s ease;
}
.site-header[data-scrolled="true"] { border-bottom-color: var(--rule); }

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-3);
  min-height: 3.75rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  text-decoration: none;
  color: var(--ink);
}
.brand:hover { color: var(--ink); }

.monogram {
  display: grid;
  place-items: center;
  width: 2rem;
  height: 2rem;
  flex: 0 0 auto;
  border: 1.5px solid var(--accent);
  border-radius: 50%;
  color: var(--accent);
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1;
  padding-left: 0.04em;
}

.brand__name {
  font-family: var(--font-display);
  font-size: 1.02rem;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.nav {
  display: none;
  align-items: center;
  gap: clamp(1rem, 2.4vw, 1.9rem);
}
@media (min-width: 40rem) { .nav { display: flex; } }

.nav a {
  color: var(--ink-2);
  text-decoration: none;
  font-size: var(--step--1);
  font-weight: 500;
  padding-block: 0.4rem;
  border-bottom: 1.5px solid transparent;
}
.nav a:hover { color: var(--ink); border-bottom-color: var(--accent); }

.theme-toggle {
  background: none;
  border: 1px solid var(--rule);
  border-radius: 50%;
  width: 2rem; height: 2rem;
  display: grid; place-items: center;
  cursor: pointer;
  color: var(--ink-3);
  flex: 0 0 auto;
}
.theme-toggle:hover { color: var(--ink); border-color: var(--rule-strong); }
.theme-toggle svg { width: 15px; height: 15px; }

.header-actions { display: flex; align-items: center; gap: var(--sp-2); }

.skip-link {
  position: absolute; left: -9999px;
  background: var(--ink); color: var(--paper);
  padding: 0.6rem 1rem; z-index: 100; border-radius: var(--radius);
}
.skip-link:focus { left: 1rem; top: 0.6rem; }

/* ---------- 6. Hero ------------------------------------------------------ */

.hero { padding-block: var(--sp-6) var(--sp-6); }
@media (min-width: 48rem) { .hero { padding-block: var(--sp-7) var(--sp-6); } }

.hero__kicker {
  display: flex; flex-wrap: wrap; align-items: center; gap: 0.6rem;
  margin-bottom: var(--sp-4);
}
.hero__kicker .dot { width: 3px; height: 3px; border-radius: 50%; background: var(--rule-strong); }

.hero h1 { max-width: 18ch; margin-bottom: var(--sp-4); }
.hero h1 em {
  font-style: italic;
  color: var(--accent);
}

.hero__lede { max-width: 40rem; }

.hero__meta {
  margin-top: var(--sp-5);
  padding-top: var(--sp-4);
  border-top: 1px solid var(--rule);
  display: grid;
  gap: var(--sp-4);
}
@media (min-width: 40rem) {
  .hero__meta { grid-template-columns: repeat(3, 1fr); gap: var(--sp-4); }
}
.hero__stat .n {
  font-family: var(--font-display);
  font-size: var(--step-2);
  line-height: 1;
  display: block;
  margin-bottom: 0.35rem;
}
.hero__stat p { font-size: var(--step--1); color: var(--ink-3); line-height: 1.45; }

/* ---------- 7. Doors (three entry points) -------------------------------- */

.doors { display: grid; gap: var(--sp-3); }
.doors { grid-template-columns: repeat(auto-fit, minmax(15.5rem, 1fr)); }

.door {
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
  padding: var(--sp-4);
  background: var(--paper-2);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  text-decoration: none;
  color: inherit;
  transition: border-color .18s ease, transform .18s ease, background .18s ease;
}
.door:hover {
  color: inherit;
  border-color: var(--accent);
  background: var(--paper);
  transform: translateY(-2px);
}
.door h3 { font-size: var(--step-1); }
.door p { font-size: var(--step--1); color: var(--ink-2); }
.door .go {
  margin-top: auto;
  padding-top: var(--sp-2);
  font-size: var(--step--2);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
}

/* ---------- 8. Study cards (the library) --------------------------------- */

.library { display: grid; gap: 0; border-top: 1px solid var(--rule); }

.study {
  display: grid;
  gap: var(--sp-3);
  padding-block: var(--sp-4);
  border-bottom: 1px solid var(--rule);
  position: relative;
}
@media (min-width: 52rem) {
  .study {
    grid-template-columns: 8.5rem 1fr;
    gap: var(--sp-4);
    padding-block: var(--sp-5);
  }
}

.study__aside { display: flex; flex-direction: column; gap: 0.3rem; }
.study__year {
  font-family: var(--font-display);
  font-size: var(--step-1);
  line-height: 1;
  color: var(--ink);
}
.study__venue { font-size: var(--step--2); color: var(--ink-3); line-height: 1.4; }

/* Publication status. Shown only when a paper is not yet in press, so a reader
   is never left to assume a venue that does not exist yet. */
.study__status {
  display: inline-block;
  align-self: start;
  margin-top: 0.25rem;
  font-size: var(--step--2);
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--ink-3);
  border: 1px solid var(--rule-strong);
  border-radius: 100px;
  padding: 0.1rem 0.5rem;
}

.study__body { min-width: 0; }

.study__title { margin-bottom: var(--sp-3); }
.study__title a { color: var(--ink); text-decoration: none; }
.study__title a:hover { color: var(--accent); }

/* the four-slot summary */
.slots { display: grid; gap: var(--sp-3); }
@media (min-width: 34rem) { .slots { grid-template-columns: 1fr 1fr; gap: var(--sp-3) var(--sp-4); } }

.slot { display: grid; gap: 0.3rem; align-content: start; }
.slot p { font-size: var(--step--1); color: var(--ink-2); line-height: 1.55; }
.slot p strong { color: var(--ink); font-weight: 600; }

.study__foot {
  display: flex; flex-wrap: wrap; align-items: center; gap: var(--sp-2) var(--sp-3);
  margin-top: var(--sp-3);
  padding-top: var(--sp-3);
  border-top: 1px dashed var(--rule);
  font-size: var(--step--1);
}

.tag {
  display: inline-block;
  font-size: var(--step--2);
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-wash);
  border-radius: 100px;
  padding: 0.18rem 0.6rem;
}
.tag--flag {
  color: #8A5A00; background: #FBF0D9;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .tag--flag { color: #E8C275; background: #332813; }
}
:root[data-theme="dark"] .tag--flag { color: #E8C275; background: #332813; }

/* ---------- 9. Buttons --------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.05rem;
  border: 1px solid var(--accent);
  border-radius: 100px;
  background: var(--accent);
  color: var(--paper);
  font-size: var(--step--1);
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: background .15s ease, border-color .15s ease, transform .15s ease;
}
.btn:hover { background: var(--accent-hover); border-color: var(--accent-hover); color: var(--paper); transform: translateY(-1px); }
:root[data-theme="dark"] .btn, :root:not([data-theme="light"]) .btn { color: #0B0D10; }
@media (prefers-color-scheme: light) { :root:not([data-theme="dark"]) .btn { color: var(--paper); } }

.btn--ghost {
  background: transparent;
  color: var(--accent);
  border-color: var(--rule-strong);
}
.btn--ghost:hover { background: var(--accent-wash); color: var(--accent); border-color: var(--accent); }

.btn--sm { padding: 0.42rem 0.85rem; font-size: var(--step--2); }

/* ---------- 10. Explainer deck ------------------------------------------- */

.deck {
  margin-block: var(--sp-4);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--paper-2);
  overflow: hidden;
}

.deck__track {
  display: flex;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  scroll-behavior: smooth;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}
.deck__track::-webkit-scrollbar { display: none; }

.slide {
  flex: 0 0 100%;
  /* min-width:auto is the flex default and lets a wide child (an SVG with a
     min-width, a table) stretch the slide past 100%, which desynchronises the
     snap points. Pin it to 0 and let wide children scroll inside instead. */
  min-width: 0;
  scroll-snap-align: center;
  scroll-snap-stop: always;
  padding: var(--sp-4) var(--sp-4) var(--sp-5);
  min-height: 25rem;
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
}
@media (min-width: 40rem) { .slide { padding: var(--sp-5); min-height: 27rem; } }

.slide__n {
  font-size: var(--step--2);
  font-family: var(--font-mono);
  color: var(--ink-3);
  letter-spacing: 0.08em;
}
.slide h3 { font-size: var(--step-2); max-width: 22ch; }
.slide p { color: var(--ink-2); max-width: 46ch; font-size: var(--step--1); }
.slide__fig {
  margin-top: auto;
  padding-top: var(--sp-3);
  overflow-x: auto;
  overscroll-behavior-x: contain; /* don't drag the deck when panning the figure */
}
.slide__sign {
  margin-top: auto;
  font-family: var(--font-display);
  font-size: var(--step-1);
  color: var(--ink-3);
}

.deck__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-3);
  border-top: 1px solid var(--rule);
  background: var(--paper);
}

.deck__dots { display: flex; gap: 0.45rem; flex-wrap: wrap; }
.deck__dot {
  width: 0.5rem; height: 0.5rem;
  border-radius: 50%;
  border: none;
  background: var(--rule-strong);
  cursor: pointer;
  padding: 0;
  transition: background .15s ease, transform .15s ease;
}
.deck__dot[aria-current="true"] { background: var(--accent); transform: scale(1.35); }

.deck__nav { display: flex; gap: 0.4rem; }
.deck__btn {
  width: 2.1rem; height: 2.1rem;
  display: grid; place-items: center;
  border: 1px solid var(--rule-strong);
  background: var(--paper);
  border-radius: 50%;
  cursor: pointer;
  color: var(--ink-2);
}
.deck__btn:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.deck__btn:disabled { opacity: 0.35; cursor: default; }
.deck__btn svg { width: 14px; height: 14px; }

.deck__hint {
  font-size: var(--step--2);
  color: var(--ink-3);
  display: none;
}
@media (min-width: 40rem) { .deck__hint { display: block; } }

/* ---------- 11. Figures -------------------------------------------------- */

.figure {
  margin-block: var(--sp-4);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: var(--sp-3);
  background: var(--paper-2);
  overflow-x: auto;
}
.figure figcaption {
  margin-top: var(--sp-2);
  font-size: var(--step--2);
  color: var(--ink-3);
  line-height: 1.5;
}

/* ---------- 11a. Ongoing work --------------------------------------------
   Deliberately lighter than a study card: no venue, no status pill, no
   citation. Work that is not yet citable must not look citable.          */

.ongoing { display: grid; gap: var(--sp-4); }
@media (min-width: 50rem) { .ongoing { grid-template-columns: 1fr 1fr; gap: var(--sp-5); } }

.ongoing__item {
  display: grid;
  gap: var(--sp-2);
  align-content: start;
  padding-left: var(--sp-3);
  border-left: 2px solid var(--rule-strong);
}
.ongoing__item h3 { font-size: var(--step-1); }
.ongoing__item p { font-size: var(--step--1); color: var(--ink-2); max-width: var(--measure); }

/* ---------- 11b. Tools ---------------------------------------------------- */

.tools { display: grid; gap: var(--sp-4); }
@media (min-width: 46rem) { .tools { grid-template-columns: 1fr 1fr; gap: var(--sp-4); } }

.tool {
  display: grid;
  gap: var(--sp-2);
  align-content: start;
  padding: var(--sp-4);
  background: var(--paper-2);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
}
.tool h3 { font-size: var(--step-2); }
.tool p { font-size: var(--step--1); color: var(--ink-2); }

.tool__head { display: flex; align-items: baseline; flex-wrap: wrap; gap: var(--sp-2); }

.badge {
  font-size: var(--step--2);
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  border: 1px solid color-mix(in srgb, var(--accent) 45%, transparent);
  border-radius: 100px;
  padding: 0.1rem 0.55rem;
}

.tool__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2) var(--sp-3);
  margin-top: var(--sp-2);
  padding-top: var(--sp-3);
  border-top: 1px dashed var(--rule);
  font-size: var(--step--1);
  word-break: break-word;
}

/* ---------- 12. Themes strand -------------------------------------------- */

.strands { display: grid; gap: var(--sp-4); }
@media (min-width: 46rem) { .strands { grid-template-columns: repeat(3, 1fr); gap: var(--sp-5); } }

.strand { display: grid; gap: var(--sp-2); align-content: start; }
.strand__n {
  font-family: var(--font-display);
  font-size: var(--step-2);
  color: var(--accent);
  line-height: 1;
}
.strand p { font-size: var(--step--1); color: var(--ink-2); }

/* ---------- 13. About ---------------------------------------------------- */

.about { display: grid; gap: var(--sp-4); align-items: start; }
@media (min-width: 46rem) {
  .about { grid-template-columns: 15rem 1fr; gap: var(--sp-5); }
}
.about__portrait {
  border-radius: var(--radius);
  border: 1px solid var(--rule);
  aspect-ratio: 4 / 5;
  object-fit: cover;
  width: 100%;
  max-width: 15rem;
  background: var(--paper-3);
  filter: saturate(0.92);
}
.about__text p { max-width: var(--measure); color: var(--ink-2); }
.about__text p:first-child { color: var(--ink); font-size: var(--step-1); font-family: var(--font-display); }

/* ---------- 14. Contact -------------------------------------------------- */

.contact { background: var(--paper-2); border-top: 1px solid var(--rule); }
.contact h2 { max-width: 16ch; }

.contact__grid { display: grid; gap: var(--sp-4); margin-top: var(--sp-5); }
@media (min-width: 40rem) { .contact__grid { grid-template-columns: repeat(2, minmax(0,1fr)); max-width: 46rem; } }

.contact__item { display: grid; gap: 0.35rem; align-content: start; }
.contact__item a, .contact__item button {
  font-family: var(--font-display);
  font-size: var(--step-1);
  color: var(--accent);
  background: none; border: none; padding: 0;
  text-align: left; cursor: pointer;
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--accent) 35%, transparent);
  text-underline-offset: 0.18em;
  word-break: break-word;
}
.contact__item a:hover, .contact__item button:hover { text-decoration-color: currentColor; }
.contact__item .note { font-size: var(--step--2); color: var(--ink-3); }

/* ---------- 15. Footer --------------------------------------------------- */

.site-footer {
  border-top: 1px solid var(--rule);
  padding-block: var(--sp-5);
  font-size: var(--step--1);
  color: var(--ink-3);
}
.site-footer__grid {
  display: grid; gap: var(--sp-3);
  align-items: baseline;
}
@media (min-width: 40rem) {
  .site-footer__grid { grid-template-columns: 1fr auto; }
}
.site-footer a { color: var(--ink-2); }
.site-footer a:hover { color: var(--accent); }
.site-footer__links { display: flex; flex-wrap: wrap; gap: var(--sp-3); }

/* ---------- 16. Study page ----------------------------------------------- */

.study-hero { padding-block: var(--sp-5) var(--sp-4); }
.back-link {
  display: inline-flex; align-items: center; gap: 0.4rem;
  font-size: var(--step--1); text-decoration: none; color: var(--ink-3);
  margin-bottom: var(--sp-4);
}
.back-link:hover { color: var(--accent); }

.study-hero h1 { font-size: var(--step-3); max-width: 24ch; margin-block: var(--sp-2) var(--sp-3); }
.study-hero .authors { font-size: var(--step--1); color: var(--ink-2); }

.keyfacts {
  display: grid; gap: var(--sp-3);
  margin-block: var(--sp-4);
  padding: var(--sp-4);
  background: var(--paper-2);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
}
@media (min-width: 34rem) { .keyfacts { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 52rem) { .keyfacts { grid-template-columns: repeat(4, 1fr); } }
.keyfact .n {
  font-family: var(--font-display); font-size: var(--step-2); line-height: 1; display: block;
  margin-bottom: 0.25rem;
}
.keyfact p { font-size: var(--step--2); color: var(--ink-3); line-height: 1.45; }

.prose { max-width: 38rem; }
.prose h2 { font-size: var(--step-2); margin-top: var(--sp-5); margin-bottom: var(--sp-3); }
.prose h3 { margin-top: var(--sp-4); margin-bottom: var(--sp-2); }
.prose ul { margin: var(--sp-3) 0; padding-left: 1.15rem; display: grid; gap: 0.5rem; }
.prose li { color: var(--ink-2); }
.prose li::marker { color: var(--accent); }

.callout {
  margin-block: var(--sp-4);
  padding: var(--sp-3) var(--sp-4);
  border-left: 2px solid var(--accent);
  background: var(--paper-2);
  border-radius: 0 var(--radius) var(--radius) 0;
}
.callout p { color: var(--ink-2); font-size: var(--step--1); }

.cite {
  font-family: var(--font-mono);
  font-size: var(--step--2);
  line-height: 1.65;
  background: var(--paper-2);
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  padding: var(--sp-3);
  color: var(--ink-2);
  white-space: pre-wrap;
  word-break: break-word;
  overflow-x: auto;
}

/* ---------- 17. Utilities ------------------------------------------------ */

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

.stack { display: grid; gap: var(--sp-3); }
.cluster { display: flex; flex-wrap: wrap; gap: var(--sp-2); align-items: center; }
.mt-4 { margin-top: var(--sp-4); }
.mt-5 { margin-top: var(--sp-5); }