/* =============================================================================
   SectraTEK Lab: lab.css
   Built on tokens.css and components.css (design system, copied unchanged). Loaded last and unlayered, so it
   wins over the design-system layers. Everything here reads tokens; no value is typed twice.
   Rules kept from the design system: no inline styles, no event-handler attributes, motion only through
   transform and opacity, and every animation sits inside the reduced-motion guard at the bottom of its block.

   Contents
     1  Lab tokens            5  Reading layout and prose      9  Callout, cite, evidence, figure
     2  Base                  6  Sections, bands, grids         10 Tabs, tree, timeline, filter, viewer
     3  Header and brand      7  Cards, chips, stats            11 Instrument panels
     4  Footer                8  Home hero                      12 Utilities, print
   ============================================================================= */

/* 1 Lab tokens -------------------------------------------------------------- */
:root {
  --paper: #ffffff;               /* reading pages are paper white in light */
  --band: var(--bg);              /* tinted bands */
  --card: #f5f5f7;
  --card-line: transparent;
  --lab-section-y: clamp(3.5rem, 2.5rem + 4vw, 6.5rem);
  --lab-read: 40rem;              /* measure for 19 px body text, about 66 characters */
  --lab-prose-size: 1.1875rem;
  --lab-head-h1: clamp(2.375rem, 1.5rem + 3.4vw, 3.875rem);
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) { --paper: var(--bg); --band: var(--canvas); --card: var(--surface); --card-line: var(--hair); }
}
:root[data-theme="dark"] { --paper: var(--bg); --band: var(--canvas); --card: var(--surface); --card-line: var(--hair); }

/* 2 Base -------------------------------------------------------------------- */
html { scroll-padding-top: calc(var(--header-h) + 1rem); }
body { background: var(--paper); color: var(--ink); }
main { display: block; outline: none; }
main:focus-visible { outline: none; }
.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
a { text-decoration-color: color-mix(in srgb, currentColor 40%, transparent); }
a:hover { text-decoration-color: currentColor; }
code { font-size: 0.9em; overflow-wrap: anywhere; }
:where(h1, h2, h3, h4) { text-wrap: balance; }
.chip--illus { background: transparent; border: 1px dashed var(--control-border); color: var(--ink-2); }
.chip--counsel { background: var(--warning-soft); color: var(--warning-ink); }
.chip--mono { font-family: var(--font-mono); letter-spacing: 0; }
.lab-id { font-family: var(--font-mono); font-size: var(--text-caption); letter-spacing: 0.02em; color: var(--ink-2); font-weight: var(--weight-medium); }
.lab-sm { font-size: var(--text-small); }
.lab-muted { color: var(--muted); }

/* 3 Header and brand -------------------------------------------------------- */
.brand--lab .brand__word { display: inline-flex; align-items: baseline; font-size: 1.1875rem; }
.brand--lab .brand__lab { margin-inline-start: 0.42em; font-weight: var(--weight-medium); color: var(--muted); letter-spacing: -0.02em; }
.brand--lab .brand__text { line-height: 1; }
.site-header__nav { justify-content: center; }
.site-header__actions { gap: 2px; }
[data-theme-cycle] .icon--lt, [data-theme-cycle] .icon--dk { display: none; }
[data-theme-cycle][data-state="light"] .icon--sys, [data-theme-cycle][data-state="dark"] .icon--sys { display: none; }
[data-theme-cycle][data-state="light"] .icon--lt, [data-theme-cycle][data-state="dark"] .icon--dk { display: inline-block; }
.site-header__menu-btn .icon--close { display: none; }
.site-header__menu-btn[aria-expanded="true"] .icon--close { display: inline-block; }
.site-header__menu-btn[aria-expanded="true"] .icon--open { display: none; }
.mobile-nav__link[aria-current="page"] { color: var(--link); }
.lab-crumbs { padding-block: var(--space-4) 0; font-size: var(--text-small); color: var(--muted); }
.lab-crumbs ol { display: flex; flex-wrap: wrap; gap: 2px 0; list-style: none; margin: 0; padding: 0; }
.lab-crumbs li { display: inline-flex; align-items: center; }
.lab-crumbs li + li::before { content: "/"; margin-inline: 0.55em; color: var(--line-strong); }
.lab-crumbs a { color: var(--muted); text-decoration: none; }
.lab-crumbs a:hover { color: var(--link); text-decoration: underline; }
.lab-crumbs [aria-current="page"] { color: var(--ink-2); }

/* 4 Footer ------------------------------------------------------------------ */
.lab-footer { margin-block-start: 0; background: var(--band); border-block-start: 1px solid var(--line); }
.lab-footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); padding-block: var(--space-8) var(--space-6); }
@media (min-width: 48em) { .lab-footer__grid { grid-template-columns: repeat(4, minmax(0, 1fr)); } }
.lab-footer__base { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--space-3) var(--space-6); padding-block: var(--space-5); border-block-start: 1px solid var(--line); }
.lab-footer__legal { margin: 0; max-width: 40rem; color: var(--muted); font-size: var(--text-caption); }
.lab-footer__proto { padding-block: var(--space-4); }
.lab-footer__proto-row { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2) var(--space-4); }
.lab-footer__proto .chip--illus { border-color: var(--navy-line); color: var(--on-navy); }
.lab-footer__proto-links { display: inline-flex; flex-wrap: wrap; gap: var(--space-4); margin-inline-start: auto; }
.lab-footer__proto-links a { color: var(--on-navy); }
@media (max-width: 47.99em) { .lab-footer__proto-links { margin-inline-start: 0; } }

/* 5 Reading layout and prose ------------------------------------------------ */
.lab-head { padding-block: clamp(3rem, 2rem + 5vw, 5.5rem) clamp(1.5rem, 1rem + 2vw, 2.5rem); }
.lab-head .eyebrow { display: block; margin-block-end: var(--space-4); }
.lab-head h1 { font-size: var(--lab-head-h1); line-height: 1.04; letter-spacing: -0.034em; font-weight: var(--weight-semibold); max-width: 18ch; text-wrap: balance; }
.lab-head--wide h1 { max-width: 22ch; }
.lab-head__lead { margin: var(--space-5) 0 0; max-width: 36rem; font-size: 1.3125rem; line-height: 1.45; letter-spacing: -0.014em; color: var(--ink-2); text-wrap: pretty; }
.lab-body { padding-block: var(--space-5) var(--lab-section-y); }
.lab-prose { max-width: var(--lab-read); font-size: var(--lab-prose-size); line-height: 1.65; letter-spacing: -0.011em; color: var(--ink); }
.lab-prose > :first-child { margin-block-start: 0; }
.lab-prose p { margin: 0 0 1.15em; }
.lab-prose h2 { margin: 2.7em 0 0.65em; font-size: clamp(1.5rem, 1.2rem + 1vw, 1.875rem); line-height: 1.18; letter-spacing: -0.024em; scroll-margin-top: 6rem; }
.lab-prose h3 { margin: 2.1em 0 0.5em; font-size: 1.3125rem; line-height: 1.3; letter-spacing: -0.016em; }
.lab-prose ul, .lab-prose ol { margin: 0 0 1.2em; padding-inline-start: 1.3em; }
.lab-prose li { margin-block: 0.4em; padding-inline-start: 0.2em; }
.lab-prose li::marker { color: var(--muted); }
.lab-prose blockquote { margin: 1.6em 0; padding-inline-start: 1.25em; border-inline-start: 3px solid var(--accent); color: var(--ink-2); }
.lab-prose hr { margin: 3em 0; }
.lab-prose a { color: var(--link); }
.lab-prose :not(pre) > code { padding: 0.1em 0.38em; border-radius: 6px; background: var(--surface-3); font-size: 0.86em; }
.lab-prose dl { margin: 0 0 1.4em; }
.lab-prose dt { font-weight: var(--weight-semibold); margin-block-start: 1em; }
.lab-prose dd { margin: 0.2em 0 0; color: var(--ink-2); }
.lab-prose .lab-callout, .lab-prose .lab-cite, .lab-prose .lab-evidence, .lab-prose .lab-figure, .lab-prose .table-wrap, .lab-prose .code-block { margin-block: 2em; }
.lab-prose .lab-lede { font-size: 1.375rem; line-height: 1.5; letter-spacing: -0.018em; color: var(--ink); }
.lab-meta-line { display: flex; flex-wrap: wrap; gap: var(--space-1) var(--space-4); margin: var(--space-5) 0 0; padding: 0; list-style: none; color: var(--muted); font-size: var(--text-small); }
.lab-meta-line li { margin: 0; }
.lab-h2-sm { font-size: 1.25rem; letter-spacing: -0.014em; margin: 2em 0 0.5em; }
.lab-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 0; }
.lab-list > li { display: flex; flex-wrap: wrap; align-items: baseline; gap: var(--space-1) var(--space-3); padding-block: var(--space-3); border-block-end: 1px solid var(--hair); }
.lab-keys { display: grid; gap: 0; margin: 0; }
.lab-keys > div { display: grid; grid-template-columns: minmax(0, 11rem) minmax(0, 1fr); gap: var(--space-4); padding-block: var(--space-3); border-block-end: 1px solid var(--hair); }
.lab-keys dt { color: var(--muted); font-size: var(--text-small); font-weight: var(--weight-medium); margin: 0; }
.lab-keys dd { margin: 0; }
@media (max-width: 39.99em) { .lab-keys > div { grid-template-columns: 1fr; gap: 2px; } }

/* article layout with a sticky contents column */
.lab-layout { display: grid; gap: var(--space-7); }
@media (min-width: 64em) { .lab-layout { grid-template-columns: 13rem minmax(0, 1fr); gap: var(--space-8); align-items: start; } }
.lab-toc { font-size: var(--text-small); }
@media (min-width: 64em) { .lab-toc { position: sticky; inset-block-start: calc(var(--header-h) + var(--space-6)); } }
.lab-toc__title { margin: 0 0 var(--space-3); font-size: var(--text-micro); letter-spacing: var(--track-eyebrow); text-transform: uppercase; font-weight: var(--weight-semibold); color: var(--muted); }
.lab-toc ol { list-style: none; margin: 0; padding: 0; display: grid; border-inline-start: 1px solid var(--line); }
.lab-toc a { display: block; padding: 6px 0 6px var(--space-4); margin-inline-start: -1px; border-inline-start: 2px solid transparent; color: var(--ink-2); text-decoration: none; }
.lab-toc a:hover { color: var(--ink); }
.lab-toc a[aria-current="true"] { color: var(--link); border-inline-start-color: var(--accent); font-weight: var(--weight-medium); }
@media (max-width: 63.99em) { .lab-toc { padding: var(--space-4); border: 1px solid var(--line); border-radius: var(--radius-md); } .lab-toc ol { border: 0; } .lab-toc a { padding-inline-start: 0; border: 0; } }

/* 6 Sections, bands, grids -------------------------------------------------- */
.lab-section { padding-block: var(--lab-section-y); }
.lab-section--tight { padding-block: clamp(2.5rem, 2rem + 2vw, 4rem); }
.lab-section__head { display: flex; flex-wrap: wrap; align-items: end; justify-content: space-between; gap: var(--space-3) var(--space-6); margin-block-end: var(--space-6); }
.lab-section__head h2 { margin: 0; font-size: clamp(1.75rem, 1.3rem + 1.6vw, 2.5rem); line-height: 1.1; letter-spacing: -0.028em; }
.lab-section__head p { margin: var(--space-2) 0 0; max-width: 34rem; color: var(--ink-2); font-size: var(--text-lead); line-height: 1.5; }
.lab-band { background: var(--band); border-block: 1px solid var(--line); }
.lab-band--plain { background: transparent; border: 0; }
.lab-grid { display: grid; gap: var(--space-5); }
.lab-grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 22rem), 1fr)); }
.lab-grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 16rem), 1fr)); }
.lab-grid--4 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 12rem), 1fr)); }
.lab-split { display: grid; gap: var(--space-6); }
@media (min-width: 52em) { .lab-split { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-8); } }
.lab-stack { display: grid; grid-template-columns: minmax(0, 1fr); gap: var(--space-4); align-content: start; }
.lab-stack > * { min-width: 0; }
.lab-stack--lg { gap: var(--space-6); }
.lab-row { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-3); }
.lab-row--between { justify-content: space-between; }
.lab-ph-page { padding-block: clamp(3rem, 2rem + 5vw, 6rem); }
.lab-ph-page h1 { font-size: var(--lab-head-h1); letter-spacing: -0.034em; line-height: 1.05; margin: var(--space-4) 0; }
.lab-ph-page .banner { margin-block: var(--space-6); }

/* 7 Cards, chips, stats ----------------------------------------------------- */
.lab-card { position: relative; display: flex; flex-direction: column; gap: var(--space-3); padding: var(--space-6); border: 1px solid var(--card-line); border-radius: var(--radius-xl); background: var(--card); color: var(--ink); }
.lab-band .lab-card { background: var(--surface); border-color: var(--line); }
.lab-card--outline { background: transparent; border-color: var(--line); }
.lab-card__top { display: flex; align-items: center; justify-content: space-between; gap: var(--space-3); }
.lab-card__title { margin: 0; font-size: 1.5rem; line-height: 1.2; letter-spacing: -0.02em; font-weight: var(--weight-semibold); text-wrap: balance; }
.lab-card--lg .lab-card__title { font-size: clamp(1.625rem, 1.3rem + 1vw, 2rem); letter-spacing: -0.026em; }
.lab-card__text { margin: 0; color: var(--ink-2); font-size: 1.0625rem; line-height: 1.55; }
.lab-card__meta { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-block-start: auto; padding-block-start: var(--space-2); }
.lab-card__foot { display: inline-flex; align-items: center; gap: 4px; margin-block-start: var(--space-2); color: var(--link); font-weight: var(--weight-medium); font-size: var(--text-ui); }
.lab-card__link { color: inherit; text-decoration: none; }
.lab-card__link::after { content: ""; position: absolute; inset: 0; border-radius: inherit; }
.lab-card__link:focus-visible { outline: none; }
.lab-card:has(.lab-card__link:focus-visible) { outline: var(--focus-width) solid var(--focus); outline-offset: var(--focus-offset); }
.lab-card--link { transition: transform var(--dur-base) var(--ease-out), box-shadow var(--dur-base) var(--ease-out), border-color var(--dur-base) var(--ease-out); }
.lab-card--link:hover { border-color: var(--line-strong); box-shadow: var(--shadow-1); }
.lab-card--link:hover .lab-card__foot .icon { transform: translateX(3px); }
.lab-card__foot .icon { transition: transform var(--dur-fast) var(--ease-out); }
@media (hover: hover) and (prefers-reduced-motion: no-preference) { html:not([data-motion="reduce"]) .lab-card--link:hover { transform: translateY(-2px); } }
.lab-chips { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.lab-chipbtn { display: inline-flex; align-items: center; gap: 6px; min-height: 36px; padding: 0 var(--space-4); border: 1px solid var(--line-strong); border-radius: var(--radius-pill); background: var(--surface); color: var(--ink); font-size: var(--text-ui); font-weight: var(--weight-medium); text-decoration: none; cursor: pointer; transition: background var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out); }
.lab-chipbtn:hover { border-color: var(--accent); color: var(--link); text-decoration: none; }
.lab-chipbtn[aria-pressed="true"] { background: var(--accent-fill); border-color: var(--accent-fill); color: var(--on-accent); }
.lab-chipbtn .lab-chipbtn__n { color: var(--muted); font-weight: var(--weight-regular); font-variant-numeric: tabular-nums; }
.lab-chipbtn[aria-pressed="true"] .lab-chipbtn__n { color: var(--on-accent); opacity: 0.85; }
.lab-stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 9rem), 1fr)); gap: var(--space-5) var(--space-6); margin: 0; padding: 0; list-style: none; }
.lab-stat { display: grid; gap: var(--space-1); padding-block-start: var(--space-4); border-block-start: 1px solid var(--line-strong); }
.lab-stat__value { font-size: clamp(2.25rem, 1.8rem + 1.6vw, 3.25rem); line-height: 1; letter-spacing: -0.035em; font-weight: var(--weight-semibold); font-variant-numeric: tabular-nums; }
.lab-stat__label { color: var(--ink-2); font-size: var(--text-ui); }
.lab-stat .chip { justify-self: start; margin-block-start: var(--space-1); }
.lab-link-list { list-style: none; margin: 0; padding: 0; display: grid; }
.lab-link-list a { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); padding-block: var(--space-4); border-block-end: 1px solid var(--line); color: var(--ink); text-decoration: none; font-size: 1.125rem; font-weight: var(--weight-medium); letter-spacing: -0.012em; }
.lab-link-list a:hover { color: var(--link); }
.lab-link-list a span { color: var(--muted); font-weight: var(--weight-regular); font-size: var(--text-small); letter-spacing: 0; }

/* 8 Home hero --------------------------------------------------------------- */
.lab-hero { position: relative; overflow: hidden; background: var(--grad-navy-hero); color: var(--on-navy); --focus: var(--focus-on-navy); --link: var(--navy-accent); padding-block: clamp(4rem, 2.5rem + 6vw, 8rem) clamp(3.5rem, 2.5rem + 4vw, 6rem); }
.lab-hero .eyebrow { color: var(--navy-accent); }
.lab-hero h1 { margin: var(--space-4) 0 0; max-width: 20ch; color: var(--on-navy); font-size: clamp(2.75rem, 1.5rem + 5.4vw, 5.75rem); line-height: 1.0; letter-spacing: -0.04em; font-weight: var(--weight-semibold); text-wrap: balance; }
.lab-hero__lead { margin: var(--space-6) 0 0; max-width: 38rem; font-size: clamp(1.1875rem, 1rem + 0.7vw, 1.5rem); line-height: 1.45; letter-spacing: -0.016em; color: var(--on-navy-2); text-wrap: pretty; }
.lab-hero__actions { display: flex; flex-wrap: wrap; gap: var(--space-3); margin-block-start: var(--space-7); }
.lab-hero .btn--secondary { --btn-bg: var(--white-12); --btn-bd: var(--navy-line); --btn-fg: var(--on-navy); --btn-state: var(--white); }
.lab-trail { position: relative; margin: clamp(3rem, 2rem + 4vw, 5.5rem) 0 0; padding: 0; list-style: none; display: grid; gap: var(--space-6); counter-reset: trail; }
.lab-trail::before { content: ""; position: absolute; background: var(--navy-line); inset-inline-start: 5px; inset-block: 6px; width: 1px; transform-origin: top; }
.lab-trail > li { position: relative; padding-inline-start: var(--space-6); display: grid; gap: 2px; align-content: start; }
.lab-trail > li::before { content: ""; position: absolute; inset-inline-start: 0; inset-block-start: 6px; width: 11px; height: 11px; border-radius: 50%; background: var(--navy); border: 2px solid var(--navy-accent); }
.lab-trail > li:first-child::before { background: var(--navy-accent); }
.lab-trail__t { font-family: var(--font-mono); font-size: var(--text-caption); letter-spacing: 0.02em; color: var(--navy-accent); }
.lab-trail__what { font-size: var(--text-ui); color: var(--on-navy); line-height: 1.4; }
.lab-trail__note { margin: var(--space-5) 0 0; font-size: var(--text-caption); color: var(--on-navy-2); line-height: 1.8; }
.lab-trail__note .chip { margin-inline-end: var(--space-2); }
.lab-hero .chip--illus { border-color: var(--navy-line); color: var(--on-navy-2); }
@media (min-width: 52em) {
  .lab-trail { grid-template-columns: repeat(5, minmax(0, 1fr)); gap: var(--space-5); }
  .lab-trail::before { inset-inline: 5px 0; inset-block: auto; inset-block-start: 5px; height: 1px; width: auto; transform-origin: left; }
  .lab-trail > li { padding-inline-start: 0; padding-block-start: var(--space-5); }
  .lab-trail > li::before { inset-block-start: 0; }
  .lab-trail > li { margin-block-start: 0; }
}
@media (prefers-reduced-motion: no-preference) {
  html:not([data-motion="reduce"]) .lab-trail::before { animation: trail-draw 2.4s var(--ease-inout) 0.3s both; }
  html:not([data-motion="reduce"]) .lab-trail > li { animation: trail-in var(--dur-hero) var(--ease-out) both; }
  html:not([data-motion="reduce"]) .lab-trail > li:nth-child(1) { animation-delay: 0.5s; }
  html:not([data-motion="reduce"]) .lab-trail > li:nth-child(2) { animation-delay: 0.95s; }
  html:not([data-motion="reduce"]) .lab-trail > li:nth-child(3) { animation-delay: 1.4s; }
  html:not([data-motion="reduce"]) .lab-trail > li:nth-child(4) { animation-delay: 1.85s; }
  html:not([data-motion="reduce"]) .lab-trail > li:nth-child(5) { animation-delay: 2.3s; }
}
@keyframes trail-draw { from { transform: scaleX(0); } to { transform: scaleX(1); } }
@keyframes trail-in { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }
@media (max-width: 51.99em) {
  @media (prefers-reduced-motion: no-preference) { html:not([data-motion="reduce"]) .lab-trail::before { animation-name: trail-draw-y; } }
}
@keyframes trail-draw-y { from { transform: scaleY(0); } to { transform: scaleY(1); } }

/* 9 Callout, cite, evidence, figure ----------------------------------------- */
.lab-callout { display: grid; grid-template-columns: auto 1fr; gap: var(--space-3) var(--space-4); padding: var(--space-5); border-radius: var(--radius-card); background: var(--accent-soft); border: 1px solid transparent; font-size: 1.0625rem; line-height: 1.55; letter-spacing: -0.008em; }
.lab-callout > .icon { color: var(--accent); margin-block-start: 2px; }
.lab-callout__title { margin: 0 0 4px; font-weight: var(--weight-semibold); color: var(--ink); }
.lab-callout p { margin: 0; color: var(--ink-2); }
.lab-callout p + p { margin-block-start: var(--space-2); }
.lab-callout--limit { background: var(--surface-2); border-color: var(--line); }
.lab-callout--limit > .icon { color: var(--ink-2); }
.lab-callout--caution { background: var(--warning-soft); }
.lab-callout--caution > .icon { color: var(--warning); }
.lab-cite { display: grid; gap: var(--space-3); padding: var(--space-5); border: 1px solid var(--line); border-radius: var(--radius-card); background: var(--surface-2); }
.lab-cite__label { margin: 0; font-size: var(--text-micro); letter-spacing: var(--track-eyebrow); text-transform: uppercase; font-weight: var(--weight-semibold); color: var(--muted); }
.lab-cite__text { margin: 0; font-size: 1rem; line-height: 1.55; color: var(--ink); letter-spacing: -0.006em; overflow-wrap: anywhere; }
.lab-cite__actions { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.lab-evidence { border: 1px solid var(--line-strong); border-radius: var(--radius-xl); background: var(--surface); overflow: hidden; }
.lab-evidence__head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--space-3); padding: var(--space-4) var(--space-5); background: var(--surface-2); border-block-end: 1px solid var(--line); }
.lab-evidence__head h2, .lab-evidence__head h3 { margin: 0; font-size: var(--text-ui); letter-spacing: -0.006em; font-weight: var(--weight-semibold); }
.lab-evidence__list { display: grid; margin: 0; padding: 0 var(--space-5); }
.lab-evidence__list > div { display: grid; gap: 2px var(--space-5); padding-block: var(--space-4); border-block-end: 1px solid var(--hair); font-size: 1rem; line-height: 1.5; letter-spacing: -0.006em; }
.lab-evidence__list > div:last-child { border-block-end: 0; }
.lab-evidence__list dt { color: var(--muted); font-size: var(--text-small); font-weight: var(--weight-medium); margin: 0; }
.lab-evidence__list dd { margin: 0; color: var(--ink); }
@media (min-width: 40em) { .lab-evidence__list > div { grid-template-columns: 11rem minmax(0, 1fr); } }
.lab-evidence__limit { background: var(--surface-2); margin-inline: calc(var(--space-5) * -1); padding-inline: var(--space-5) !important; }
.lab-figure { margin-inline: 0; }
.lab-figure__media { border: 1px solid var(--line); border-radius: var(--radius-xl); background: var(--surface); overflow: hidden; }
.lab-figure__media > svg, .lab-figure__media > img { width: 100%; height: auto; }
.lab-figure figcaption { margin-block-start: var(--space-3); font-size: var(--text-small); line-height: 1.5; color: var(--ink-2); letter-spacing: -0.004em; max-width: var(--lab-read); }
.lab-figure__num { font-weight: var(--weight-semibold); color: var(--ink); margin-inline-end: 0.4em; font-variant-numeric: tabular-nums; }
.lab-figure__num::after { content: "."; }
.lab-figure__src { display: block; margin-block-start: 2px; color: var(--muted); }
@media (min-width: 70em) {
  .lab-figure--wide { position: relative; inset-inline-start: 50%; transform: translateX(-50%); width: min(62rem, calc(100vw - 2 * var(--gutter))); }
}
.lab-refs { list-style: none; counter-reset: ref; margin: 0; padding: 0; display: grid; gap: var(--space-3); font-size: 1rem; line-height: 1.55; }
.lab-refs > li { counter-increment: ref; display: grid; grid-template-columns: 2.5rem minmax(0, 1fr); margin: 0; padding: 0; }
.lab-refs > li::before { content: "[" counter(ref) "]"; font-family: var(--font-mono); font-size: var(--text-caption); color: var(--muted); padding-block-start: 0.2em; }

/* 10 Tabs, tree, timeline, filter, viewer ----------------------------------- */
.lab-tabs { margin-block: var(--space-5); }
.lab-tabs .tabpanel { padding-block-start: var(--space-5); }
.lab-tree, .lab-tree ul { list-style: none; margin: 0; padding: 0; }
.lab-tree ul { padding-inline-start: 18px; margin-inline-start: 11px; border-inline-start: 1px solid var(--line); }
.lab-tree li { margin: 0; }
.lab-tree__row { display: flex; align-items: center; gap: 6px; width: 100%; min-height: 32px; padding: 3px 8px; border: 0; border-radius: var(--radius-sm); background: transparent; color: var(--ink-2); font: inherit; font-size: var(--text-small); text-align: start; cursor: pointer; }
.lab-tree__row:hover { background: var(--surface-3); color: var(--ink); }
.lab-tree__row[aria-selected="true"] { background: var(--accent-soft); color: var(--link); font-weight: var(--weight-medium); }
.lab-tree__row .icon { width: 16px; height: 16px; color: var(--muted); }
.lab-tree__row[aria-selected="true"] .icon { color: var(--accent); }
.lab-tree__chev { transition: transform var(--dur-fast) var(--ease-out); }
.lab-tree__row[aria-expanded="true"] .lab-tree__chev { transform: rotate(90deg); }
.lab-tree__spacer { width: 16px; flex: none; }
.lab-tree__name { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.lab-tree__size { margin-inline-start: auto; font-family: var(--font-mono); font-size: var(--text-micro); color: var(--muted); }
@media (prefers-reduced-motion: no-preference) { html:not([data-motion="reduce"]) .lab-tree ul:not([hidden]) { animation: tree-in var(--dur-base) var(--ease-out) both; } }
@keyframes tree-in { from { opacity: 0; transform: translateY(-4px); } to { opacity: 1; transform: none; } }

.lab-tl { position: relative; display: flex; gap: 0; margin: 0; padding: var(--space-6) var(--space-5) var(--space-5); list-style: none; overflow-x: auto; }
.lab-tl::before { content: ""; position: absolute; inset-inline: var(--space-5); inset-block-start: calc(var(--space-6) + 11px); height: 1px; background: var(--line-strong); transform-origin: left; }
.lab-tl > li { position: relative; flex: 1 0 7.5rem; margin: 0; padding: 0; display: grid; justify-items: start; gap: 6px; }
.lab-tl__node { position: relative; display: inline-grid; place-items: center; width: 24px; height: 24px; padding: 0; border: 0; border-radius: 50%; background: transparent; cursor: pointer; }
.lab-tl__node::before { content: ""; width: 12px; height: 12px; border-radius: 50%; background: var(--surface); border: 2px solid var(--accent); transition: transform var(--dur-fast) var(--ease-out), background var(--dur-fast) var(--ease-out); }
.lab-tl__node:hover::before { transform: scale(1.25); }
.lab-tl__node[aria-pressed="true"]::before { background: var(--accent-fill); transform: scale(1.3); box-shadow: var(--ring-accent); }
.lab-tl__t { font-family: var(--font-mono); font-size: var(--text-caption); color: var(--ink-2); }
.lab-tl__label { font-size: var(--text-small); color: var(--ink); line-height: 1.35; padding-inline-end: var(--space-3); }
.lab-pick-panel { padding: var(--space-5); border-block-start: 1px solid var(--line); background: var(--surface-2); }
.lab-pick-panel h3 { margin: 0 0 var(--space-3); font-size: var(--text-h4); letter-spacing: -0.014em; }
.lab-pick-panel[hidden] { display: none; }
@media (prefers-reduced-motion: no-preference) { html:not([data-motion="reduce"]) .lab-pick-panel:not([hidden]) { animation: tree-in var(--dur-base) var(--ease-out) both; } html:not([data-motion="reduce"]) .lab-figure.is-in .lab-tl::before { animation: trail-draw 1.6s var(--ease-inout) both; } }

.lab-filterbar { display: grid; gap: var(--space-4); padding-block: var(--space-5); border-block: 1px solid var(--line); }
.lab-filterbar__row { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2) var(--space-3); }
.lab-filterbar__label { min-width: 6rem; font-size: var(--text-small); font-weight: var(--weight-medium); color: var(--muted); }
.lab-filterbar__count { margin: 0; font-size: var(--text-small); color: var(--muted); }
.lab-empty { padding: var(--space-8) var(--space-5); text-align: center; border: 1px dashed var(--line-strong); border-radius: var(--radius-xl); color: var(--ink-2); }
.lab-empty h3 { margin: 0 0 var(--space-2); font-size: var(--text-h4); letter-spacing: -0.012em; }
.lab-empty p { margin: 0 auto; max-width: 28rem; }
[data-filter-item][hidden] { display: none !important; }

.lab-viewer { display: grid; grid-template-rows: auto 1fr; min-height: 22rem; border-radius: var(--radius-xl); overflow: hidden; }
.lab-viewer__bar { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--space-3); padding: var(--space-3) var(--space-4); border-block-end: 1px solid var(--navy-line); }
.lab-viewer__path { min-width: 0; font-family: var(--font-mono); font-size: var(--text-caption); color: var(--on-navy-2); overflow-wrap: anywhere; }
.lab-viewer__main { display: grid; grid-template-columns: 1fr; min-height: 0; }
@media (min-width: 56em) { .lab-viewer__main { grid-template-columns: minmax(0, 1fr) 18rem; } }
.lab-viewer__content { margin: 0; padding: var(--space-4); overflow: auto; font-family: var(--font-mono); font-size: 0.8125rem; line-height: 1.65; color: var(--on-navy); white-space: pre; max-height: 26rem; }
.lab-viewer__side { padding: var(--space-4); border-inline-start: 1px solid var(--navy-line); display: grid; gap: var(--space-3); align-content: start; font-size: var(--text-small); color: var(--on-navy-2); }
@media (max-width: 55.99em) { .lab-viewer__side { border-inline-start: 0; border-block-start: 1px solid var(--navy-line); } }
.lab-viewer__side h3 { margin: 0; font-size: var(--text-micro); letter-spacing: var(--track-eyebrow); text-transform: uppercase; color: var(--navy-accent); font-weight: var(--weight-semibold); }
.lab-viewer__side p { margin: 0; }
.lab-hex-off { color: var(--muted); }

/* 11 Instrument panels (dark in both themes) -------------------------------- */
.lab-instrument { background: var(--navy-2); color: var(--ink); border: 1px solid var(--navy-line); border-radius: var(--radius-xl); --link: #9ccdff; }
.lab-instrument.lab-figure__media { border-color: var(--navy-line); background: var(--navy-2); }
.lab-instrument .lab-tl::before { background: var(--navy-line); }
.lab-instrument .lab-tl__node::before { background: var(--navy-2); }
.lab-instrument .lab-pick-panel { background: transparent; border-color: var(--navy-line); }
.lab-instrument .lab-tl__label { color: var(--on-navy); }
.lab-instrument .lab-tl__t { color: var(--navy-accent); }
.lab-instrument .lab-tree__row { color: var(--on-navy-2); }
.lab-instrument .lab-tree__row:hover { background: var(--white-12); color: var(--on-navy); }
.lab-instrument .lab-tree__row[aria-selected="true"] { background: var(--accent-soft); color: #9ccdff; }
.lab-instrument .lab-tree ul { border-color: var(--navy-line); }
.lab-instrument .tabs { border-color: var(--navy-line); }
.lab-instrument .btn--secondary { --btn-bg: var(--white-12); --btn-bd: var(--navy-line); --btn-fg: var(--on-navy); --btn-state: var(--white); }

/* 12 Utilities, motion switch, print ---------------------------------------- */
[data-reveal] { transition: opacity var(--dur-slow) var(--ease-out), transform var(--dur-slow) var(--ease-out); }
html.js [data-reveal].will-reveal { opacity: 0; transform: translateY(var(--shift-sm)); }
html.js [data-reveal].will-reveal.is-in { opacity: 1; transform: none; }
html[data-motion="reduce"] [data-reveal], html[data-motion="reduce"] [data-reveal].will-reveal { opacity: 1 !important; transform: none !important; transition: none; }
@media (prefers-reduced-motion: reduce) { [data-reveal], [data-reveal].will-reveal { opacity: 1 !important; transform: none !important; transition: none; } }
html[data-motion="reduce"] *, html[data-motion="reduce"] *::before, html[data-motion="reduce"] *::after { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; scroll-behavior: auto !important; }
.toast-region { pointer-events: none; }
.sr-live { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); }
@media print {
  .site-header, .mobile-nav, .site-footer, .lab-toc, .skip-link, .toast-region, dialog { display: none !important; }
  body { background: #fff; color: #000; }
  .lab-prose { max-width: none; font-size: 11pt; }
  a { color: inherit; }
}

/* 13 Page-level helpers (home and shared) */
.lab-note { margin: var(--space-5) 0 0; }
.lab-split__title { margin: var(--space-3) 0 0; font-size: clamp(1.75rem, 1.3rem + 1.6vw, 2.5rem); line-height: 1.12; letter-spacing: -0.028em; max-width: 18ch; }
.lab-lede-sm { margin: 0; font-size: 1.1875rem; line-height: 1.55; letter-spacing: -0.012em; color: var(--ink-2); max-width: 36rem; }
.lab-card .eyebrow { display: block; }

.lab-nf-actions { margin-block: var(--space-6) var(--space-7); }
.lab-searchform { margin-block-start: var(--space-6); }
.lab-search-note { margin: var(--space-4) 0 var(--space-5); }
.lab-results { list-style: none; margin: 0; padding: 0; display: grid; }
.lab-results a { display: grid; gap: 2px; padding-block: var(--space-4); border-block-end: 1px solid var(--line); color: var(--ink); text-decoration: none; }
.lab-results a:hover strong { color: var(--link); }
.lab-results strong { font-size: 1.1875rem; letter-spacing: -0.012em; }

/* 14 Components page ---------------------------------------------------------- */
.lab-cmp { padding-block: var(--space-7); border-block-start: 1px solid var(--line); scroll-margin-top: 5rem; }
.lab-cmp:first-of-type { border-block-start: 0; }
.lab-cmp > h2 { margin: 0 0 var(--space-3); font-size: 1.75rem; letter-spacing: -0.024em; }
.lab-cmp > p { margin: 0 0 var(--space-5); max-width: 44rem; color: var(--ink-2); }
.lab-cmp code { padding: 0.1em 0.38em; border-radius: 6px; background: var(--surface-3); font-size: 0.86em; }
.lab-cmp-toc { display: flex; flex-wrap: wrap; gap: var(--space-2) var(--space-4); padding-block: var(--space-4) var(--space-6); font-size: var(--text-small); }
.lab-cmp-toc a { color: var(--ink-2); text-decoration: none; }
.lab-cmp-toc a:hover { color: var(--link); text-decoration: underline; }
.lab-demo { padding: var(--space-5); border: 1px dashed var(--line-strong); border-radius: var(--radius-card); }
.lab-keys--compact > div { padding-block: var(--space-2); grid-template-columns: minmax(0, 7rem) minmax(0, 1fr); }
.lab-keys--compact { font-size: var(--text-small); }
.lab-svg-bg { fill: var(--surface-2); }
.lab-svg-axis { stroke: var(--line-strong); stroke-width: 1.5; }
.lab-svg-dot { fill: var(--surface); stroke: var(--accent); stroke-width: 2.5; }
.lab-svg-text { fill: var(--ink-2); font-family: var(--font-mono); font-size: 14px; }
.lab-tree-status { margin: var(--space-4) 0 0; color: var(--on-navy-2); }
.lab-form-demo { display: grid; gap: var(--space-5); max-width: 32rem; }
.lab-crumbs--demo { padding: 0 0 var(--space-5); }
.lab-toc--demo { max-width: 16rem; padding: var(--space-4); border: 1px solid var(--line); border-radius: var(--radius-md); position: static; }
.lab-filter-list { list-style: none; margin: var(--space-5) 0 0; padding: 0; }
.lab-skeleton-demo { display: grid; gap: var(--space-2); max-width: 24rem; margin-block-start: var(--space-5); }
.lab-meta-line-wrap { margin-block-start: var(--space-2); }
.lab-demo + .lab-grid { margin-block-start: var(--space-5); }
.lab-empty p + p { margin-block-start: var(--space-3); }
.palette__input::-webkit-search-cancel-button { display: none; }
@media (forced-colors: active) {
  .lab-chipbtn[aria-pressed="true"] { border: 2px solid Highlight; }
  .lab-chipbtn, .lab-card, .lab-evidence, .lab-cite, .lab-callout, .lab-instrument, .lab-figure__media { border: 1px solid CanvasText; }
  .lab-tl__node::before { border-color: CanvasText; }
  .lab-tl__node[aria-pressed="true"]::before { background: Highlight; }
  .lab-tree__row[aria-selected="true"] { outline: 2px solid Highlight; }
  .lab-toc a[aria-current="true"] { border-inline-start-color: Highlight; }
}