/* ============================================================
   MD NAD — Y2K Aesthetic: Chrome + Iridescent Console
   Deep space-chrome ground, glossy bubble components
   Space Grotesk headings, Inter body, JetBrains Mono data layer
   ============================================================ */

/* ---- CSS Variables ---- */
:root {
  --primary:              #7DF9FF;
  --primary-50:           #E6FCFE;
  --primary-500:          #19BFD3;
  --primary-700:          #0E7E8E;
  --secondary:            #C8A6FF;
  --iridescent-cyan:      #7DF9FF;
  --iridescent-magenta:   #FF7AD9;
  --iridescent-violet:    #A78BFA;
  --chrome-light:         #E8ECF4;
  --chrome-mid:           #AEB7C9;
  --chrome-dark:          #6B7488;
  --chrome-shadow:        #3A4154;
  --accent:               #FF7AD9;
  --accent-strong:        #F24FC0;
  --space-black:          #0A0E1A;
  --space-black-2:        #0F1424;
  --space-black-3:        #161D32;
  --space-black-4:        #1F2742;
  --neutral-50:           #EEF1F8;
  --neutral-100:          #D6DCEA;
  --neutral-200:          #AEB7C9;
  --neutral-300:          #7E879B;
  --neutral-500:          #5A6275;
  --neutral-700:          #343B4F;
  --bg:                   #0A0E1A;
  --surface:              #0F1424;
  --surface-elevated:     #161D32;
  --surface-glass:        rgba(22, 29, 50, 0.62);
  --surface-inverse:      #EEF1F8;
  --border:               rgba(174, 183, 201, 0.20);
  --border-strong:        rgba(174, 183, 201, 0.38);
  --text:                 #E8ECF4;
  --text-strong:          #FFFFFF;
  --text-muted:           #AEB7C9;
  --text-dim:             #7E879B;
  --text-on-chrome:       #0A0E1A;
  --success:              #74E0A8;
  --warning:              #F2C14E;
  --danger:               #FF7A8A;

  --chrome-gradient:      linear-gradient(160deg, #FFFFFF 0%, #E8ECF4 22%, #AEB7C9 48%, #6B7488 72%, #E8ECF4 100%);
  --iridescent-gradient:  linear-gradient(120deg, #7DF9FF 0%, #A78BFA 45%, #FF7AD9 100%);
  --hero-halo-gradient:   radial-gradient(circle at 50% 40%, rgba(125,249,255,0.28) 0%, rgba(167,139,250,0.18) 38%, rgba(255,122,217,0.10) 62%, rgba(10,14,26,0) 80%);
  --iridescent-border:    linear-gradient(120deg, #7DF9FF 0%, #C8A6FF 50%, #FF7AD9 100%);

  --max-width:            74rem;
  --content-max-width:    44rem;
  --table-max-width:      62rem;
  --hero-text-column:     32rem;
  --container-px:         clamp(1rem, 3vw, 2.25rem);

  --font-display:         'Space Grotesk', 'Eurostile', 'Bank Gothic', system-ui, sans-serif;
  --font-body:            'Inter', system-ui, -apple-system, 'Segoe UI', 'Helvetica Neue', sans-serif;
  --font-mono:            'JetBrains Mono', 'IBM Plex Mono', 'SF Mono', Menlo, Consolas, monospace;

  --radius-button:        9999px;
  --radius-card:          1.25rem;
  --radius-callout:       1rem;
  --radius-chip:          9999px;
  --radius-figure:        1.25rem;
}

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

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *, *::before, *::after {
    transition-duration: 0ms !important;
    animation-duration: 0ms !important;
  }
}

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.68;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

img, video { max-width: 100%; display: block; }
a { color: inherit; }
ul, ol { list-style: none; }

/* ---- Container ---- */
.container {
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--container-px);
}

.container--content {
  max-width: var(--content-max-width);
  margin-inline: auto;
  padding-inline: var(--container-px);
}

.container--table {
  max-width: var(--table-max-width);
  margin-inline: auto;
  padding-inline: var(--container-px);
}

/* ---- Typography ---- */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  color: var(--text-strong);
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2.25rem, 4.8vw, 3.625rem);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(1.625rem, 3vw, 2.375rem);
  font-weight: 600;
  line-height: 1.14;
  letter-spacing: -0.015em;
}

h3 {
  font-size: 1.4375rem;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

h4 {
  font-size: 1.0625rem;
  font-weight: 500;
  line-height: 1.2;
  letter-spacing: -0.005em;
}

p {
  line-height: 1.68;
  color: var(--text);
}

p + p {
  margin-top: 1rem;
}

strong { font-weight: 600; color: var(--text-strong); }
em { font-style: italic; }

small {
  font-size: 0.875rem;
  line-height: 1.55;
  letter-spacing: 0.005em;
}

.lede {
  font-size: 1.1875rem;
  line-height: 1.55;
  color: var(--text);
}

.eyebrow {
  font-family: var(--font-display);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--text-on-chrome);
}

code, .mono {
  font-family: var(--font-mono);
  font-size: 0.9375rem;
  line-height: 1.5;
  font-variant-numeric: tabular-nums;
}

/* Inline mono chip */
.mono-chip {
  font-family: var(--font-mono);
  font-size: 0.92em;
  background: var(--space-black-3);
  border-left: 1px solid var(--iridescent-cyan);
  border-radius: 0.375rem;
  padding: 0.0625rem 0.4rem;
  color: var(--iridescent-cyan);
}

/* Superscript citations */
sup a {
  font-size: 0.75em;
  color: var(--iridescent-cyan);
  text-decoration: none;
  vertical-align: super;
  font-family: var(--font-mono);
  font-weight: 500;
  transition: color 200ms ease-out;
}
sup a:hover { color: var(--iridescent-magenta); }

/* ---- Iridescent gradient text utility ---- */
.text-chrome {
  background: var(--chrome-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ---- Focus states ---- */
:focus-visible {
  outline: 2.5px solid var(--iridescent-cyan);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---- Skip link ---- */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  background: var(--surface-elevated);
  color: var(--text-strong);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-card);
  font-size: 0.875rem;
  z-index: 1000;
  text-decoration: none;
  transition: top 200ms ease-out;
}
.skip-link:focus {
  top: 1rem;
}

/* ---- Site Header ---- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: 72px;
  background: var(--surface-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  background-image: linear-gradient(var(--surface-glass), var(--surface-glass)),
                    linear-gradient(120deg, #7DF9FF 0%, #C8A6FF 50%, #FF7AD9 100%);
  background-origin: border-box;
  background-clip: padding-box, border-box;
  transition: background 200ms ease-out;
}

.site-header.scrolled {
  background: rgba(22, 29, 50, 0.78);
}

.site-header .container {
  display: flex;
  align-items: center;
  gap: 2rem;
  height: 72px;
}

/* Brand chip + wordmark */
.site-brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  flex-shrink: 0;
}

.brand-chip {
  width: 22px;
  height: 22px;
  border-radius: 5px;
  background: var(--chrome-gradient);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.8), 0 1px 2px rgba(58,65,84,0.6);
  flex-shrink: 0;
}

.brand-wordmark {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  background: var(--chrome-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-shadow: none;
}

/* Nav */
.site-nav {
  flex: 1;
  display: flex;
  justify-content: center;
}

.site-nav ul {
  display: flex;
  gap: 1.75rem;
  align-items: center;
}

.site-nav a {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
  position: relative;
  padding-bottom: 3px;
  transition: color 200ms ease-out;
}

.site-nav a::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--iridescent-gradient);
  transition: width 200ms ease-out;
}

.site-nav a:hover {
  color: var(--text-strong);
}

.site-nav a:hover::after {
  width: 100%;
}

.site-nav a.active {
  color: var(--text-strong);
}

.site-nav a.active::after {
  width: 100%;
}

.header-cta {
  flex-shrink: 0;
}

/* Mobile nav toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  margin-left: auto;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-muted);
  border-radius: 1px;
  transition: all 200ms ease-out;
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  border: none;
  cursor: pointer;
  border-radius: var(--radius-button);
  padding: 0.875rem 1.75rem;
  transition: all 200ms ease-out;
  white-space: nowrap;
  position: relative;
}

.btn-primary {
  background: var(--chrome-gradient);
  color: var(--text-on-chrome);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.8),
              0 0 0 1px transparent;
  background-origin: border-box;
}

.btn-primary::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-button);
  padding: 1px;
  background: var(--iridescent-gradient);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0.6;
  transition: opacity 200ms ease-out;
}

.btn-primary:hover::before { opacity: 1; }

.btn-primary:hover {
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.8),
              0 0 18px rgba(125,249,255,0.35);
}

.btn-secondary {
  background: transparent;
  color: var(--text-strong);
  border: 1.5px solid var(--chrome-mid);
  transition: border-color 200ms ease-out, color 200ms ease-out;
}

.btn-secondary:hover {
  border-color: transparent;
  background-image: var(--iridescent-gradient);
  background-origin: border-box;
  color: var(--text-on-chrome);
}

.btn-ghost {
  background: none;
  border: none;
  color: var(--text-strong);
  padding: 0;
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: var(--iridescent-cyan);
  font-size: 0.9375rem;
}

.btn-ghost:hover {
  text-decoration-color: var(--iridescent-magenta);
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
}

/* ---- Hero ---- */
.hero {
  min-height: 86vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 5rem;
  padding-bottom: 5rem;
}

.hero-bg-halo {
  position: absolute;
  inset: 0;
  background: var(--hero-halo-gradient);
  pointer-events: none;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
  width: 100%;
}

.hero-text {
  max-width: var(--hero-text-column);
}

.hero-eyebrow-pill {
  display: inline-flex;
  align-items: center;
  background: var(--chrome-gradient);
  border-radius: var(--radius-chip);
  padding: 0.375rem 1rem;
  margin-bottom: 1.5rem;
  position: relative;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.8);
}

.hero-eyebrow-pill::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-chip);
  padding: 1px;
  background: var(--iridescent-gradient);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
}

.hero h1 {
  margin-bottom: 1.25rem;
}

.hero-subheadline {
  font-size: 1.1875rem;
  line-height: 1.55;
  color: var(--text);
  max-width: 56ch;
  margin-bottom: 2rem;
}

/* Hero stat strip */
.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 2.5rem;
}

.stat-bubble {
  background: var(--surface-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-radius: 1rem;
  padding: 0.75rem 1rem;
  min-width: 100px;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.06);
}

.stat-bubble .stat-label {
  font-family: var(--font-body);
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  display: block;
  margin-bottom: 0.25rem;
}

.stat-bubble .stat-value {
  font-family: var(--font-mono);
  font-size: clamp(1rem, 2.2vw, 1.5rem);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--text-strong);
  line-height: 1.1;
  display: block;
}

/* Hero image */
.hero-image-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-figure {
  border-radius: var(--radius-figure);
  border: 1px solid rgba(125,249,255,0.4);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.10),
              0 8px 48px rgba(0,0,0,0.6);
  overflow: hidden;
  max-width: 100%;
}

.hero-figure img {
  width: 100%;
  display: block;
}

/* ---- Subpage hero ---- */
.subpage-hero {
  height: 260px;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
  padding-top: 2rem;
}

.subpage-hero-bg {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 80%, rgba(125,249,255,0.12) 0%, rgba(10,14,26,0) 70%);
  pointer-events: none;
}

.subpage-hero-content {
  position: relative;
}

/* ---- Section structure ---- */
.page-section {
  padding-block: 5rem;
  border-bottom: 1px solid var(--border);
}

.page-section:last-child {
  border-bottom: none;
}

/* Section marker */
.section-marker {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.section-chip {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  background: var(--chrome-gradient);
  color: var(--text-on-chrome);
  padding: 0.25rem 0.625rem;
  border-radius: 0.375rem;
  letter-spacing: 0.05em;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.6);
  white-space: nowrap;
}

.section-index {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--iridescent-cyan);
  letter-spacing: 0.05em;
}

/* Iridescent H2 rail */
.section-h2-wrap {
  margin-bottom: 0.5rem;
}

.section-h2-wrap h2 {
  margin-bottom: 0.5rem;
}

.accent-rail {
  width: 3rem;
  height: 2px;
  background: var(--iridescent-gradient);
  margin-bottom: 1.5rem;
  border-radius: 1px;
}

/* ---- Cards ---- */
.card {
  background: var(--surface-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  padding: 1.75rem;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.10),
              0 8px 28px rgba(0,0,0,0.45);
}

.card + .card {
  margin-top: 1.5rem;
}

.card-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--iridescent-cyan);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}

.card h3 {
  margin-bottom: 0.75rem;
}

.card-divider {
  height: 1px;
  background: var(--border);
  margin-block: 1rem;
}

.card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
  margin-top: 1rem;
}

.card-meta {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
}

/* Featured card — iridescent border */
.card-featured {
  position: relative;
}

.card-featured::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-card);
  padding: 1.5px;
  background: var(--iridescent-gradient);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
}

/* Evidence cards grid */
.cards-grid {
  display: grid;
  gap: 1.25rem;
}

.cards-grid-2 {
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 20rem), 1fr));
}

/* ---- Callouts ---- */
.callout {
  background: var(--surface-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-left: 4px solid var(--iridescent-cyan);
  border-radius: var(--radius-callout);
  padding: 1.25rem 1.5rem;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.06);
  margin-block: 2rem;
}

.callout-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--iridescent-cyan);
  margin-bottom: 0.5rem;
}

.callout-safety {
  border-left-color: var(--warning);
}

.callout-safety .callout-eyebrow {
  color: var(--warning);
}

.callout-fda {
  border-left-color: var(--iridescent-violet);
}

.callout-fda .callout-eyebrow {
  color: var(--iridescent-violet);
}

/* ---- Pull quotes ---- */
.pull-quote {
  text-align: center;
  padding-block: 3rem;
  position: relative;
}

.pull-quote-glyph {
  font-family: var(--font-display);
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 0.5;
  background: var(--iridescent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 1.25rem;
  display: block;
}

.pull-quote blockquote {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 2.6vw, 2rem);
  font-weight: 600;
  color: var(--text-strong);
  max-width: 40ch;
  margin-inline: auto;
  line-height: 1.3;
}

.pull-quote-rule {
  width: 32px;
  height: 2px;
  background: var(--iridescent-gradient);
  margin-inline: auto;
  margin-block: 1rem;
  border-radius: 1px;
}

.pull-quote-attribution {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
}

/* ---- Tables ---- */
.table-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
  border-top: 2px solid transparent;
  background-image: var(--iridescent-gradient);
  background-origin: border-box;
  background-clip: border-box;
}

.data-table::before {
  content: '';
  display: block;
  height: 2px;
  background: var(--iridescent-gradient);
}

.data-table thead th {
  font-family: var(--font-display);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--iridescent-cyan);
  text-align: left;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

.data-table thead th.numeric { text-align: right; }

.data-table tbody tr {
  border-bottom: 1px solid var(--border);
  transition: background 200ms ease-out;
}

.data-table tbody tr:hover {
  background: rgba(22, 29, 50, 0.5);
}

.data-table tbody td {
  padding: 1rem 1.25rem;
  color: var(--text);
  vertical-align: top;
}

.data-table tbody td.numeric {
  text-align: right;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* ---- Chips ---- */
.chip {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.7rem;
  border-radius: var(--radius-chip);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.04em;
}

.chip-chrome {
  background: var(--chrome-gradient);
  color: var(--text-on-chrome);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.6);
}

.chip-iridescent {
  background: transparent;
  border: 1px solid transparent;
  background-image: linear-gradient(var(--bg), var(--bg)), var(--iridescent-gradient);
  background-origin: border-box;
  background-clip: padding-box, border-box;
  color: var(--text-strong);
  font-family: var(--font-mono);
  letter-spacing: 0.12em;
}

.chip-status {
  background: var(--surface-glass);
  border: 1px solid var(--border);
  color: var(--text-muted);
}

/* ---- Figure / image ---- */
.figure-wrap {
  margin-block: 2.5rem;
}

.figure-inner {
  border-radius: var(--radius-figure);
  border: 1px solid rgba(125,249,255,0.4);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.10),
              0 8px 28px rgba(0,0,0,0.45);
  overflow: hidden;
}

.figure-inner img {
  width: 100%;
  display: block;
}

.figure-caption {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 0.75rem;
  padding-inline: 0.25rem;
}

.figure-caption strong {
  font-weight: 600;
  color: var(--text);
}

/* ---- Sections ---- */
.page-prose {
  padding-block: 5rem;
}

.prose-body {
  max-width: var(--content-max-width);
  margin-inline: auto;
}

.prose-body h2 {
  margin-top: 3rem;
  margin-bottom: 0.5rem;
}

.prose-body h3 {
  margin-top: 2rem;
  margin-bottom: 0.5rem;
}

.prose-body p {
  margin-bottom: 1rem;
}

.prose-body ul,
.prose-body ol {
  list-style: none;
  padding: 0;
  margin-bottom: 1rem;
}

.prose-body ul li,
.prose-body ol li {
  padding-left: 1.5em;
  position: relative;
  margin-bottom: 0.5rem;
}

.prose-body ul li::before {
  content: '—';
  position: absolute;
  left: 0;
  color: var(--iridescent-cyan);
  font-family: var(--font-mono);
}

.prose-body ol {
  counter-reset: list-counter;
}

.prose-body ol li {
  counter-increment: list-counter;
}

.prose-body ol li::before {
  content: counter(list-counter) '.';
  position: absolute;
  left: 0;
  color: var(--iridescent-cyan);
  font-family: var(--font-mono);
  font-size: 0.875rem;
}

/* ---- FAQ ---- */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.faq-item {
  background: var(--surface-glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  overflow: hidden;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.06);
}

.faq-question {
  width: 100%;
  background: none;
  border: none;
  padding: 1.25rem 1.75rem;
  text-align: left;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  color: var(--text-strong);
  font-family: var(--font-display);
  font-size: 1.0625rem;
  font-weight: 600;
  transition: color 200ms ease-out;
}

.faq-question:hover {
  color: var(--iridescent-cyan);
}

.faq-icon {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  color: var(--iridescent-cyan);
  flex-shrink: 0;
  transition: transform 200ms ease-out;
  user-select: none;
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  display: none;
  padding: 0 1.75rem 1.25rem;
  color: var(--text);
  line-height: 1.68;
}

.faq-answer p + p {
  margin-top: 0.75rem;
}

/* ---- References list ---- */
.references-list {
  list-style: none;
  padding: 0;
  counter-reset: ref-counter;
}

.references-list li {
  counter-increment: ref-counter;
  display: grid;
  grid-template-columns: 2rem 1fr;
  gap: 0.75rem;
  padding-block: 1rem;
  border-bottom: 1px solid var(--border);
  font-size: 0.9375rem;
  line-height: 1.6;
  align-items: start;
}

.references-list li:last-child {
  border-bottom: none;
}

.ref-number {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--iridescent-cyan);
  text-align: right;
  padding-top: 0.1rem;
}

.ref-content {
  color: var(--text);
}

.ref-content a {
  color: var(--iridescent-cyan);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 0.875rem;
}

.ref-content a:hover {
  color: var(--iridescent-magenta);
}

/* ---- Contact form ---- */
.contact-form {
  max-width: 36rem;
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  font-family: var(--font-mono);
}

.form-input,
.form-textarea {
  width: 100%;
  background: var(--surface-elevated);
  border: 1px solid var(--border-strong);
  border-radius: 0.5rem;
  padding: 0.75rem 1rem;
  color: var(--text);
  font-family: var(--font-body);
  font-size: 1rem;
  transition: border-color 200ms ease-out;
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--iridescent-cyan);
}

.form-textarea {
  min-height: 120px;
  resize: vertical;
}

/* ---- Footer ---- */
.site-footer {
  background: var(--surface);
  border-top: 1px solid transparent;
  background-image: linear-gradient(var(--surface), var(--surface)),
                    linear-gradient(120deg, rgba(125,249,255,0.4) 0%, rgba(200,166,255,0.4) 50%, rgba(255,122,217,0.4) 100%);
  background-origin: border-box;
  background-clip: padding-box, border-box;
  padding-top: 4rem;
  padding-bottom: 2rem;
}

.footer-top {
  margin-bottom: 3rem;
}

.footer-section-marker {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 2rem;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
  margin-bottom: 3rem;
}

.footer-col-heading {
  font-family: var(--font-display);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--iridescent-cyan);
  margin-bottom: 1rem;
}

.footer-col ul {
  list-style: none;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-col a {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 200ms ease-out;
  position: relative;
}

.footer-col a:hover {
  color: var(--text-strong);
}

.footer-divider {
  height: 1px;
  background: var(--border);
  margin-bottom: 1.5rem;
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-disclaimer {
  font-size: 0.875rem;
  font-style: italic;
  color: var(--text-muted);
  max-width: 36rem;
}

.footer-colophon {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-dim);
  text-align: right;
  letter-spacing: 0.05em;
}

/* ---- Breadcrumbs ---- */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.breadcrumbs a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 200ms ease-out;
}

.breadcrumbs a:hover { color: var(--iridescent-cyan); }

.breadcrumb-sep {
  color: var(--text-dim);
  font-family: var(--font-mono);
}

/* ---- 404 ---- */
.error-page {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
}

.error-code {
  font-family: var(--font-mono);
  font-size: clamp(4rem, 12vw, 8rem);
  font-weight: 700;
  background: var(--iridescent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 1rem;
}

/* ---- Tippy overrides ---- */
.tippy-box {
  background: var(--surface-glass) !important;
  backdrop-filter: blur(14px) !important;
  -webkit-backdrop-filter: blur(14px) !important;
  border: 1px solid transparent !important;
  background-image: linear-gradient(var(--surface-glass), var(--surface-glass)),
                    var(--iridescent-gradient) !important;
  background-origin: border-box !important;
  background-clip: padding-box, border-box !important;
  border-radius: 1.25rem !important;
  box-shadow: 0 8px 28px rgba(0,0,0,0.5) !important;
  color: var(--text) !important;
  font-size: 0.875rem !important;
  max-width: 280px !important;
  padding: 1rem !important;
}

.tippy-box .tippy-doi {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--iridescent-cyan);
  display: block;
  margin-top: 0.5rem;
  word-break: break-all;
}

.tippy-arrow { display: none !important; }

/* ---- Reading progress ---- */
.reading-progress {
  position: fixed;
  top: 72px;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--iridescent-gradient);
  z-index: 99;
  transition: width 100ms linear;
}

/* ---- Utility / one-off helpers (no inline styles) ---- */

.error-heading {
  margin-bottom: 1rem;
}

.error-lede {
  margin-bottom: 2rem;
  max-width: 40ch;
  margin-inline: auto;
}

.cta-row--center {
  justify-content: center;
}

.callout-para-2 {
  margin-top: 0.75rem;
}

.contact-form--spaced {
  margin-top: 2.5rem;
}

.prose-body--refs {
  margin-top: 2rem;
}

.figure-wrap--spaced {
  margin-top: 3rem;
}

/* ============================================================
   Responsive
   ============================================================ */

@media (max-width: 1023px) {
  .footer-cols {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 767px) {
  .hero {
    min-height: 100svh;
    padding-top: 2rem;
    padding-bottom: 3rem;
  }

  .hero-inner {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .hero-image-wrap {
    order: -1;
  }

  .hero-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
  }

  .site-nav {
    display: none;
    position: fixed;
    inset: 72px 0 0 0;
    background: rgba(10,14,26,0.97);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: stretch;
    padding: 2rem;
    z-index: 99;
  }

  .site-nav.open {
    display: flex;
  }

  .site-nav ul {
    flex-direction: column;
    gap: 0;
  }

  .site-nav li {
    border-bottom: 1px solid var(--border);
  }

  .site-nav a {
    display: block;
    padding: 1rem 0;
    font-size: 1.125rem;
  }

  .nav-toggle {
    display: flex;
  }

  .header-cta {
    display: none;
  }

  .footer-cols {
    grid-template-columns: 1fr 1fr;
  }

  .footer-bottom {
    flex-direction: column;
  }

  .footer-colophon {
    text-align: left;
  }

  .subpage-hero {
    height: auto;
    min-height: 200px;
    padding-block: 3rem;
  }

  .cards-grid-2 {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 479px) {
  .footer-cols {
    grid-template-columns: 1fr;
  }

  .hero-stats {
    grid-template-columns: 1fr;
  }

  .cta-row {
    flex-direction: column;
    align-items: flex-start;
  }
}