/* ==========================================================================
   Solar Operations Maturity Institute (SOM Institute) · website variant 1 · "Meridian"
   Research-institute / editorial. One stylesheet, mobile-first, no build.

   1  Tokens          every design decision, as custom properties
   2  Base            reset, type, links, focus
   3  Masthead & CTA  slim fixed bar (from 60em) · fixed pill (below 60em)
   4  Layout          wrap, sections, the margin column
   5  Components      level glyphs, the spine, figures, ruled lists
   6  Pages           model ladders and index, about, privacy, model history
   7  Closing band & footer
   8  Motion & print
   ========================================================================== */


/* 1 TOKENS ================================================================= */

:root {
  color-scheme: light;

  /* Colour: navy ink on warm paper, one solar-amber accent.
     Amber is reserved for "the sun": the mark's level-5 node, the level-5
     glyph and the survey button. It is never set as text on paper (1.9:1);
     navy text on amber is 7.8:1. Contrast figures are against --paper. */
  --paper:       #fbfaf6;  /* ground */
  --paper-2:     #f3f0e7;  /* one quiet band per page, never a card */
  --ink:         #0f2241;  /* navy: text, weighted rules, the mark (15.2:1) */
  --ink-2:       #33415c;  /* secondary text (9.8:1) */
  --muted:       #56627a;  /* labels and captions (5.9:1) */
  --rule:        #d9d3c4;  /* hairlines; decorative only */
  --amber:       #f4a71d;  /* solar amber */
  --amber-deep:  #e08f08;  /* button hover (navy on it: 6.1:1) */
  --amber-edge:  #b67400;  /* button edge, 3.7:1 against paper */
  --night:       #0b1a33;  /* closing band and footer */
  --night-ink:   #eef0f4;  /* 15.2:1 on night */
  --night-muted: #b4bdcd;  /* 9.2:1 on night */
  --night-rule:  rgba(238, 240, 244, 0.16);

  /* Type: a serif for everything read as display, a humanist sans for
     reading and interface. Both fall back to fonts already on the machine. */
  --serif: "Newsreader", "Iowan Old Style", "Sitka Text", Charter, "Bitstream Charter", Cambria, Georgia, serif;
  --sans:  "Source Sans 3", "Source Sans Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, Roboto, "Helvetica Neue", Arial, sans-serif;

  --fs-label:   0.8125rem;                                    /* 13px, uppercase labels */
  --fs-small:   0.9375rem;                                    /* 15px, captions */
  --fs-body:    1.0625rem;                                    /* 17px; 18px from 60em */
  --fs-lede:    clamp(1.25rem, 1.08rem + 0.75vw, 1.6rem);
  --fs-h3:      clamp(1.25rem, 1.14rem + 0.45vw, 1.5rem);
  --fs-h2:      clamp(1.9rem, 1.45rem + 1.95vw, 3rem);
  --fs-h1:      clamp(2.35rem, 1.6rem + 3.3vw, 4.25rem);
  --fs-display: clamp(2.5rem, 1.55rem + 4.2vw, 4.5rem);

  /* Space and grid */
  --gutter:        clamp(1.25rem, 0.55rem + 3vw, 3.5rem);
  --wrap:          72rem;
  --measure:       37rem;
  --margin-col:    11.5rem;
  --space-section: clamp(3.75rem, 2.4rem + 5.5vw, 7.5rem);

  /* The survey call to action */
  --bar-h:   4rem;     /* desktop: slim fixed top bar */
  --pill-h:  3.25rem;  /* phones: the pill, 52px tall */
  --folio-h: calc(var(--pill-h) + 1.25rem + 1px);  /* phones: the strip that carries it */
}


/* 2 BASE =================================================================== */

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  /* Anything scrolled to (anchors, keyboard focus) stops clear of the folio */
  scroll-padding-bottom: calc(var(--folio-h) + 1.5rem + env(safe-area-inset-bottom, 0px));
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: var(--fs-body);
  line-height: 1.6;
  font-kerning: normal;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, svg { max-width: 100%; }

h1, h2, h3 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 500;
  line-height: 1.1;
  letter-spacing: -0.015em;
  overflow-wrap: break-word;
  text-wrap: balance;
}
h1 { font-size: var(--fs-h1); }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); font-weight: 600; line-height: 1.25; letter-spacing: -0.005em; }

p, ul, ol, dl, dd, figure { margin: 0; }
p { text-wrap: pretty; }
strong, b { font-weight: 700; }

a {
  color: inherit;
  text-decoration-line: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}
a:hover { text-decoration-thickness: 2px; }

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

:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 3px;
}
.on-night :focus-visible { outline-color: var(--amber); }

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }

.skip-link {
  position: absolute;
  z-index: 100;
  top: 0.75rem;
  left: var(--gutter);
  padding: 0.7rem 1.1rem;
  background: var(--ink);
  color: var(--paper);
  font-weight: 700;
  text-decoration: none;
  transform: translateY(-180%);
}
.skip-link:focus { transform: none; }


/* 3 MASTHEAD & THE SURVEY CTA ============================================== */
/* Below 60em the masthead scrolls away with the page and the nav's last
   item, the survey link, detaches into a pill fixed above the bottom edge.
   From 60em the whole masthead becomes a slim bar fixed to the top and the
   same link sits at its right-hand end. Either way it never leaves the
   viewport, and on a phone it never sits over the nav, which is at the top. */

.masthead {
  background: var(--paper);
  border-bottom: 1px solid var(--rule);
}
.masthead__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  column-gap: 2rem;
  padding-top: 0.4rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  min-height: 3rem;
  color: var(--ink);
  text-decoration: none;
}
.brand__mark {
  --mark-ground: var(--paper);
  flex: none;
  width: 2.15rem;
  height: 2.15rem;
}
/* The wordmark (2026-10-07): SOMInstitute, one word. The four capitals, S,
   O, M and I, stand upright in the serif's semibold; the rest of "Institute"
   turns into its italic, so the capitals read as one block and the word
   still reads as SOM + Institute. Under it, the full name in small sans.
   The letters keep the text colour, never amber: amber is the sun, and the
   sun is in the mark. The two-line lockup is narrower than the old one-line
   name, so the bar has more room at 960px than before, not less (DESIGN.md,
   rename note). */
.brand__text {
  display: flex;
  flex-direction: column;
  row-gap: 0.125rem;
}
.brand__name {
  font-family: var(--serif);
  font-size: 1.375rem;
  font-weight: 600;
  line-height: 1;
  letter-spacing: 0.02em;            /* the capitals, lightly spaced */
  white-space: nowrap;
}
.brand__name i {
  font-weight: 450;                  /* the site's display weight */
  letter-spacing: -0.004em;
  padding-inline: 0.02em 0.06em;     /* clear of the upright I; the italic e stays inside the link */
}
.brand__full {
  color: var(--muted);
  font-family: var(--sans);
  font-size: 0.6875rem;              /* 11px, half the wordmark */
  font-weight: 500;
  line-height: 1.2;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.nav { flex: 1 1 100%; border-top: 1px solid var(--rule); }
.nav__list {
  display: flex;
  flex-wrap: wrap;   /* five items: on the narrowest phones, or with a wider
                        fallback font, the last page link drops to a second
                        line instead of pushing the page sideways */
  align-items: center;
  gap: 0 1.25rem;
  padding: 0;
  list-style: none;
}
.nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  min-height: 2.875rem;
  color: var(--ink-2);
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
}
.nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;               /* sits on the masthead's own bottom rule */
  height: 2px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.2s ease;
}
.nav__link:hover { color: var(--ink); }
.nav__link:hover::after,
.nav__link[aria-current="page"]::after { transform: none; }
.nav__link[aria-current="page"] { color: var(--ink); }

/* The survey button, wherever it appears */
.cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  min-height: 2.875rem;
  padding: 0.55rem 1.3rem 0.55rem 1.45rem;
  border: 1px solid var(--amber-edge);
  border-radius: 999px;
  background: var(--amber);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: 0.005em;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 0.18s ease;
}
.cta:hover { background: var(--amber-deep); }
.cta__arrow { display: inline-block; transition: transform 0.18s ease; }
.cta:hover .cta__arrow { transform: translateX(0.2rem); }
.cta--large {
  min-height: 3.5rem;
  padding-inline: 1.8rem 1.6rem;
  font-size: 1.125rem;
}
.cta-meta { display: none; }

/* Phones and tablets: the nav's last item detaches into the "folio", a
   quiet paper strip fixed to the bottom edge, like the running footer of a
   printed page. It carries the same unit as the desktop bar's right-hand
   end: "Under ten minutes" and the pill. Because the folio is an opaque
   lane of its own, the pill never floats over a line of text; the page
   reserves the folio's height (see .site-footer and html scroll-padding)
   so nothing is ever stranded behind it. */
.nav__item--cta {
  position: fixed;
  z-index: 60;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.625rem var(--gutter) calc(0.625rem + env(safe-area-inset-bottom, 0px));
  border-top: 1px solid var(--rule);
  background: var(--paper);
}
.nav__item--cta .cta {
  min-height: var(--pill-h);
  padding-inline: 1.5rem 1.35rem;
  font-size: 1.0625rem;
}
.nav__item--cta .cta-meta {
  display: inline;
  color: var(--muted);
  font-size: var(--fs-small);
  line-height: 1.3;
}
@media (max-width: 22.4375em) {          /* under 360px: the pill alone, centred */
  .nav__item--cta { justify-content: center; }
  .nav__item--cta .cta-meta { display: none; }
}

@media (min-width: 40em) {
  /* tablets: the folio's note and pill travel together at the right, as in the bar */
  .nav__item--cta { justify-content: flex-end; gap: 1.25rem; }
}
/* From 48em the brand and the page links share one row. This was 40em
   until "Model history" joined the nav (2026-10-07): between 40em and 48em
   one row is now too narrow, so the nav keeps its own row there, as on
   phones. */
@media (min-width: 48em) {
  .masthead__inner { flex-wrap: nowrap; padding-top: 0; }
  .nav { flex: 0 1 auto; margin-left: auto; border-top: 0; }
  .nav__list { gap: 0 1.6rem; }
  .nav__link { min-height: 3.75rem; }
}

/* Desktop: the masthead is the slim fixed bar and the CTA lives in it */
@media (min-width: 60em) {
  html {
    scroll-padding-top: calc(var(--bar-h) + 1.25rem);
    scroll-padding-bottom: 0;
  }
  body {
    padding-top: var(--bar-h);
    font-size: 1.125rem;
  }
  .masthead {
    position: fixed;
    z-index: 50;
    top: 0;
    left: 0;
    right: 0;
    height: var(--bar-h);
  }
  .masthead__inner { height: 100%; }
  .nav__link { min-height: calc(var(--bar-h) - 1px); }
  .nav__item--cta {
    position: static;
    gap: 1rem;
    margin-left: 0.25rem;
    padding: 0;
    border-top: 0;
    background: none;
  }
  .nav__item--cta .cta {
    min-height: 2.875rem;
    padding-inline: 1.3rem 1.15rem;
    font-size: 1rem;
  }
  .nav__item--cta .cta-meta { display: none; }
}
@media (min-width: 75em) {
  .nav__list { gap: 0 2rem; }   /* 1.6rem below 75em, so five items fit the bar at 960px */
  .nav__item--cta .cta-meta { display: inline; white-space: nowrap; }
}


/* 4 LAYOUT ================================================================= */

.wrap {
  width: 100%;
  max-width: calc(var(--wrap) + 2 * var(--gutter));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--space-section); }
.section + .section { border-top: 1px solid var(--rule); }
.section--band {
  --surface: var(--paper-2);
  background: var(--paper-2);
}
.section + .section--band,
.section--band + .section { border-top: 0; }

.section__grid { display: grid; row-gap: 1.4rem; }
.section__aside { align-self: start; }
.section__title { max-width: 20ch; }
.section__intro {
  margin-top: 1.25rem;
  max-width: var(--measure);
  color: var(--ink-2);
}
.section__more {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 2rem;
  margin-top: 2rem;
}

@media (min-width: 60em) {
  .section__grid {
    grid-template-columns: var(--margin-col) minmax(0, 1fr);
    column-gap: clamp(2.5rem, 1rem + 3vw, 5rem);
  }
  /* The section label rides down the margin like a running head */
  .section__aside {
    position: sticky;
    top: calc(var(--bar-h) + 2.75rem);
    padding-top: 0.6rem;
  }
}

.kicker {
  font-family: var(--sans);
  font-size: var(--fs-label);
  font-weight: 700;
  line-height: 1.35;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}
.kicker--rule::before {
  content: "";
  display: block;
  width: 2.25rem;
  height: 2px;
  margin-bottom: 0.85rem;
  background: var(--ink);
}
.on-night .kicker { color: var(--night-muted); }
.on-night .kicker--rule::before { background: var(--night-ink); }

.flow > * + * { margin-top: var(--flow-space, 1em); }
.prose { max-width: var(--measure); }

/* One drop cap, on the opening paragraph of the landing page's argument */
.dropcap::first-letter {
  float: left;
  margin: 0.07em 0.09em 0 -0.03em;
  font-family: var(--serif);
  font-size: 3.6em;
  font-weight: 500;
  line-height: 0.8;
  color: var(--ink);
}

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  min-height: 2.875rem;
  color: var(--ink);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.3em;
}
.link-arrow::after {
  content: "\2192";
  content: "\2192" / "";
  display: inline-block;
  transition: transform 0.18s ease;
}
.link-arrow:hover::after { transform: translateX(0.2rem); }

.page-head {
  padding-block: clamp(2.5rem, 1.25rem + 4.5vw, 5.5rem) clamp(2.75rem, 1.5rem + 3.5vw, 4.75rem);
  border-bottom: 1px solid var(--rule);
}
.page-head__title { margin-top: 1.4rem; max-width: 17ch; }
.page-head__lede {
  margin-top: 1.5rem;
  max-width: 36rem;
  font-family: var(--serif);
  font-size: var(--fs-lede);
  line-height: 1.4;
  color: var(--ink-2);
}


/* 5 COMPONENTS ============================================================= */

/* Hero ------------------------------------------------------------------- */
.hero { padding-block: clamp(2rem, 0.75rem + 3vw, 4rem) clamp(3rem, 2rem + 4vw, 5.5rem); }
.hero__grid { display: grid; gap: clamp(2.75rem, 1.5rem + 3vw, 4rem); }
.hero__title {
  margin-top: 1.25rem;
  font-size: var(--fs-display);
  font-weight: 450;
  line-height: 1.02;
  letter-spacing: -0.024em;
}
.hero__lede {
  margin-top: 1.4rem;
  max-width: 33em;
  font-family: var(--serif);
  font-size: clamp(1.175rem, 1.04rem + 0.6vw, 1.45rem);
  line-height: 1.42;
  color: var(--ink-2);
}
.hero__sub { margin-top: 1.1rem; max-width: var(--measure); }
.hero__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.75rem;
  margin-top: 2rem;
}
.meta-list {
  display: flex;
  flex-wrap: wrap;
  margin-top: 1.25rem;
  padding: 0;
  list-style: none;
  color: var(--muted);
  font-size: var(--fs-small);
}
.meta-list li:not(:last-child)::after {
  content: "\00B7";
  content: "\00B7" / "";
  margin-inline: 0.6em;
}
.hero__figure { align-self: end; }
.hero__figure .mfig {
  display: block;
  width: 100%;
  max-width: 25rem;
  height: auto;
  margin-inline: auto;
}
@media (min-width: 60em) {
  .hero__grid {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    align-items: end;
    column-gap: clamp(3rem, 1rem + 4vw, 6rem);
  }
  .hero__figure .mfig { margin-right: 0; }
}

/* Figure captions, journal style */
.fig-caption {
  margin-top: 1rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: var(--fs-small);
  line-height: 1.5;
}
.fig-caption b { margin-right: 0.4em; color: var(--ink); }

/* The meridian figure: an arc from the horizon to the meridian, six nodes */
.mfig { color: var(--ink); overflow: visible; }
.mfig__guides { fill: none; stroke: var(--rule); stroke-width: 1; }
.mfig__inner { stroke-dasharray: 2 5; }
.mfig__frame { fill: none; stroke: var(--ink); stroke-width: 1.25; stroke-linecap: round; }
.mfig__arc { fill: none; stroke: var(--ink); stroke-width: 2; }
.mfig__node { fill: var(--ink); }
.mfig__node--0 { fill: var(--paper); stroke: var(--ink); stroke-width: 2; }
.mfig__node--5 { fill: var(--amber); }
.mfig__halo { fill: none; stroke: var(--amber); stroke-width: 1.5; }
.mfig__labels text {
  fill: var(--ink);
  font-family: var(--serif);
  font-size: 22px;
  font-variant-numeric: lining-nums;
  text-anchor: middle;
}

/* "On this page": the argument's table of contents */
.onpage {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  column-gap: 1.5rem;
  padding-block: 0.35rem;
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--rule);
}
.onpage .kicker { margin-right: 0.25rem; padding-block: 0.6rem; }
.onpage__list {
  display: flex;
  flex-wrap: wrap;
  column-gap: 1.4rem;
  padding: 0;
  list-style: none;
}
.onpage__list a {
  display: inline-flex;
  align-items: center;
  min-height: 2.875rem;
  color: var(--ink-2);
  font-weight: 600;
  text-decoration: none;
}
.onpage__list a:hover { color: var(--ink); text-decoration: underline; }

/* Level glyphs: the model's numerals. 0 is an empty ring, 5 is the sun. */
.lvl {
  position: relative;
  z-index: 1;
  display: inline-grid;
  place-items: center;
  flex: none;
  width: 3rem;
  height: 3rem;
  padding-bottom: 0.06em;
  border-radius: 50%;
  background: var(--surface, var(--paper));
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.85rem;
  font-weight: 400;
  line-height: 1;
  font-variant-numeric: lining-nums tabular-nums;
}
.lvl--0 { box-shadow: inset 0 0 0 1.5px var(--ink); }
.lvl--5 { background: var(--amber); }

/* The spine: six levels in a row on wide screens, a ruled list on phones */
.spine {
  margin-top: 2.5rem;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--ink);
}
.spine__item {
  display: flex;
  align-items: center;
  gap: 1.1rem;
  padding-block: 0.6rem;
  border-bottom: 1px solid var(--rule);
}
.spine__name {
  font-family: var(--serif);
  font-size: 1.25rem;
  line-height: 1.25;
}
@media (min-width: 48em) {
  .spine {
    position: relative;
    display: grid;
    grid-template-columns: repeat(6, minmax(0, 1fr));
    padding-top: 1.5rem;
    border-top: 0;
  }
  /* the horizon, running through the centre of every glyph */
  .spine::before {
    content: "";
    position: absolute;
    top: calc(1.5rem + 1.5rem);
    left: 1.5rem;
    right: calc(100% / 6 - 1.5rem);
    height: 1px;
    background: var(--ink);
  }
  .spine__item {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.85rem;
    padding: 0 1rem 0 0;
    border: 0;
  }
  .spine__name { font-size: 1.15rem; }
}

/* A specimen: one area at the two ends of its ladder */
.specimen { margin-top: 3rem; border-top: 2px solid var(--ink); }
.specimen__cap {
  padding-block: 0.9rem;
  color: var(--ink-2);
  font-family: var(--serif);
  font-size: 1.15rem;
  font-style: italic;
}
.specimen__rung {
  position: relative;
  display: grid;
  grid-template-columns: 3rem minmax(0, 1fr);
  column-gap: 1.25rem;
  align-items: start;
  padding-block: 1.1rem 1.3rem;
  border-top: 1px solid var(--rule);
}
.specimen__rung--from::after,
.specimen__rung--to::before {
  content: "";
  position: absolute;
  left: calc(1.5rem - 0.5px);
  border-left: 1px solid var(--ink);
}
.specimen__rung--from::after { top: calc(1.1rem + 1.5rem); bottom: 0; }
.specimen__rung--to::before { top: -1px; height: calc(1.1rem + 1.5rem + 1px); }
.specimen__title {
  padding-top: 0.2rem;
  color: var(--muted);
  font-size: var(--fs-label);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.specimen__quote {
  margin-top: 0.35rem;
  font-family: var(--serif);
  font-size: var(--fs-h3);
  line-height: 1.38;
}
.specimen__between {
  position: relative;
  padding: 0.85rem 0 0.85rem 4.25rem;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: var(--fs-small);
}
.specimen__between::before {
  content: "";
  position: absolute;
  left: calc(1.5rem - 0.5px);
  top: 0;
  bottom: 0;
  border-left: 1px dashed var(--ink);
}

/* The seven areas, as a ruled, numbered list */
.areas {
  margin-top: 3rem;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--ink);
}
.areas__item {
  display: grid;
  grid-template-columns: 2.5rem minmax(0, 1fr);
  column-gap: 0.75rem;
  row-gap: 0.2rem;
  padding-block: 1rem 1.1rem;
  border-bottom: 1px solid var(--rule);
}
.areas__num {
  grid-row: 1 / span 2;
  padding-top: 0.2rem;
  color: var(--muted);
  font-family: var(--serif);
  font-size: 1.05rem;
  font-weight: 500;
  letter-spacing: 0.06em;
}
.areas__item { position: relative; }
.areas__name a { text-decoration-color: var(--rule); }
.areas__name a::after {              /* the whole row is the link's tap target */
  content: "";
  position: absolute;
  inset: 0;
}
.areas__name a:hover { text-decoration-color: currentColor; }
.areas__covers { color: var(--ink-2); }
@media (min-width: 48em) {
  .areas__item {
    grid-template-columns: 3rem 12.5rem minmax(0, 1fr);
    column-gap: 1.25rem;
    align-items: baseline;
  }
  .areas__num { grid-row: auto; padding-top: 0; }
}

/* The four survey paths */
.paths {
  display: grid;
  column-gap: clamp(2rem, 1rem + 3vw, 4rem);
  margin-top: 2.5rem;
  padding: 0;
  list-style: none;
}
.path {
  padding-block: 1.25rem 1.5rem;
  border-top: 1px solid var(--ink);
}
.path__label,
.return__n,
.step__n,
.area__num {
  color: var(--muted);
  font-size: var(--fs-label);
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.path__quote {
  margin-top: 0.6rem;
  font-family: var(--serif);
  font-size: var(--fs-h3);
  font-style: italic;
  line-height: 1.35;
  text-indent: -0.42em;   /* hang the opening quote mark */
}
.path__note { margin-top: 0.5rem; color: var(--muted); font-size: var(--fs-small); }
@media (min-width: 48em) {
  .paths { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

.readers {
  display: grid;
  row-gap: 0.4rem;
  max-width: var(--measure);
  margin-top: 2rem;
  padding-top: 1.1rem;
  border-top: 1px solid var(--rule);
  color: var(--ink-2);
}

/* What a respondent receives */
.returns {
  display: grid;
  gap: 2rem;
  margin-top: 2.5rem;
  padding: 0;
  list-style: none;
}
.return { padding-top: 1.1rem; border-top: 2px solid var(--ink); }
.return__title { margin-top: 0.5rem; }
.return__text { margin-top: 0.6rem; color: var(--ink-2); }
.note-line {
  max-width: var(--measure);
  margin-top: 2.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--rule);
}
@media (min-width: 48em) {
  .returns {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: clamp(1.5rem, 0.5rem + 2vw, 3rem);
  }
}

/* The survey's anatomy, set as a sentence */
.anatomy {
  max-width: 30ch;
  margin-top: 1.25rem;
  color: var(--ink-2);
  font-family: var(--serif);
  font-size: var(--fs-lede);
  font-style: italic;
  line-height: 1.35;
}
.nowrap { white-space: nowrap; }

/* Ruled definition lists: survey mechanics, scoring, privacy */
.facts { margin-top: 2.5rem; border-top: 1px solid var(--ink); }
.facts__row {
  display: grid;
  row-gap: 0.4rem;
  padding-block: 1.15rem 1.25rem;
  border-bottom: 1px solid var(--rule);
}
.facts dt {
  color: var(--ink);
  font-size: var(--fs-label);
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.facts dd { max-width: var(--measure); color: var(--ink-2); }
.facts dd > * + * { margin-top: 0.75em; }
@media (min-width: 48em) {
  .facts__row {
    grid-template-columns: 12rem minmax(0, 1fr);
    column-gap: 2rem;
  }
  .facts dt { padding-top: 0.3rem; }
}

/* Partners: four names in one ruled row with equal billing (the same size,
   weight and spacing, always in the brief's order). A ruled list on phones,
   two by two from 30em, one row from 48em. On the landing page one small
   line follows: who developed the model, and a link to its history. */
.partners {
  display: grid;
  margin-top: 2.25rem;
  padding: 0;
  list-style: none;
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--rule);
}
.partner {
  padding-block: 0.85rem 0.95rem;
  font-family: var(--serif);
  font-size: clamp(1.3rem, 1.15rem + 0.5vw, 1.6rem);
  font-weight: 450;
  line-height: 1.2;
  letter-spacing: -0.01em;
  text-wrap: balance;
}
.partner + .partner { border-top: 1px solid var(--rule); }
.partners__note {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  column-gap: 1.25rem;
  margin-top: 0.75rem;
  color: var(--muted);
  font-size: var(--fs-small);
}
@media (min-width: 30em) {
  .partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 1.5rem;
  }
  .partner + .partner { border-top: 0; }
  .partner:nth-child(n + 3) { border-top: 1px solid var(--rule); }
}
@media (min-width: 48em) {
  .partners {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    column-gap: clamp(1.25rem, 0.5rem + 1.5vw, 2.25rem);
  }
  .partner { padding-block: 1.05rem 1.2rem; }
  .partner:nth-child(n + 3) { border-top: 0; }
}

/* Spacing that the long-form sections share */
.section__body > .prose { margin-top: 1.75rem; }
.section__body > .prose.flow { --flow-space: 1.1em; }
.list-label { margin-top: 3.5rem; }
.list-label + .areas,
.list-label + .facts { margin-top: 1rem; }


/* 6 PAGES ================================================================== */

/* The model: contents */
.toc__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  column-gap: 1rem;
  margin-top: 2rem;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--ink);
}
.toc__link {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  min-height: 3rem;
  padding-block: 0.75rem;
  border-bottom: 1px solid var(--rule);
  color: var(--ink);
  text-decoration: none;
}
.toc__link:hover .toc__name {
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}
.toc__num {
  flex: none;
  min-width: 2.1rem;
  color: var(--muted);
  font-family: var(--serif);
  font-size: 1rem;
  font-weight: 500;
  letter-spacing: 0.06em;
}
.toc__name { font-family: var(--serif); font-size: 1.15rem; line-height: 1.25; }
@media (min-width: 48em) {
  .toc__list { grid-template-columns: repeat(4, minmax(0, 1fr)); column-gap: 1.75rem; }
}

/* The model: one chapter per area */
.area {
  padding-block: clamp(3.25rem, 2rem + 4.5vw, 6rem);
  border-top: 1px solid var(--rule);
}
.area + .section { border-top: 1px solid var(--rule); }
.area__grid { display: grid; row-gap: 2rem; }
.area__num::before {
  content: "";
  display: block;
  width: 2.25rem;
  height: 2px;
  margin-bottom: 0.85rem;
  background: var(--ink);
}
.area__name { margin-top: 0.75rem; }
.area__covers {
  max-width: 30rem;
  margin-top: 1rem;
  color: var(--ink-2);
  font-family: var(--serif);
  font-size: var(--fs-lede);
  font-style: italic;
  line-height: 1.4;
}
.area__back { margin-top: 1rem; font-size: var(--fs-small); }
.area__back a {
  display: inline-flex;
  align-items: center;
  min-height: 2.875rem;
  color: var(--muted);
}
@media (min-width: 60em) {
  .area__grid {
    grid-template-columns: minmax(0, 17rem) minmax(0, 1fr);
    column-gap: clamp(3rem, 1.5rem + 4vw, 6rem);
  }
  .area__head {
    position: sticky;
    top: calc(var(--bar-h) + 2.5rem);
    align-self: start;
  }
}

/* The ladder: six rungs joined by a meridian line through the glyphs */
.ladder {
  padding: 0;
  list-style: none;
  border-top: 2px solid var(--ink);
}
.rung {
  position: relative;
  display: grid;
  grid-template-columns: 3rem minmax(0, 1fr);
  column-gap: clamp(1rem, 0.5rem + 1.6vw, 1.9rem);
  padding-block: 1.3rem 1.4rem;
  border-bottom: 1px solid var(--rule);
}
.rung::before {
  content: "";
  position: absolute;
  left: calc(1.5rem - 0.5px);
  top: calc(1.3rem + 1.5rem);
  bottom: calc(-1.3rem - 1.5rem - 1px);
  border-left: 1px solid var(--ink);
}
.rung:last-child::before { content: none; }
.rung__spine {
  padding-top: 0.25rem;
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.rung__title {
  margin-top: 0.3rem;
  font-family: var(--serif);
  font-size: var(--fs-h3);
  font-weight: 600;
  line-height: 1.25;
}
.rung__desc { max-width: 36rem; margin-top: 0.45rem; color: var(--ink-2); }

/* The model: index by level */
.index { margin-top: 2.25rem; border-top: 1px solid var(--ink); }
.index__row {
  display: grid;
  row-gap: 1rem;
  padding-block: 1.4rem;
  border-bottom: 1px solid var(--rule);
}
.index__level {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-family: var(--serif);
  font-size: 1.3rem;
  line-height: 1.2;
}
.index__terms ul {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 9.25rem), 1fr));
  gap: 0.9rem 1.25rem;
  padding: 0;
  list-style: none;
}
.index__area {
  display: block;
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.index__term { font-family: var(--serif); font-size: 1.1rem; line-height: 1.3; }
@media (min-width: 48em) {
  .index__row {
    grid-template-columns: 11rem minmax(0, 1fr);
    column-gap: 2rem;
    align-items: start;
  }
}

/* About: who it helps */
.helps {
  display: grid;
  column-gap: clamp(2rem, 1rem + 3vw, 4rem);
  margin-top: 2.5rem;
  padding: 0;
  list-style: none;
}
.help { padding-block: 1.3rem 1.5rem; border-top: 1px solid var(--ink); }
.help__text { margin-top: 0.55rem; color: var(--ink-2); }
@media (min-width: 48em) {
  .helps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

/* About: how the survey works */
.steps {
  margin-top: 2.5rem;
  padding: 0;
  list-style: none;
  border-top: 2px solid var(--ink);
}
.step {
  display: grid;
  row-gap: 0.35rem;
  padding-block: 1.3rem 1.4rem;
  border-bottom: 1px solid var(--rule);
}
.step__text { max-width: var(--measure); color: var(--ink-2); }
@media (min-width: 48em) {
  .step {
    grid-template-columns: 6.5rem minmax(0, 1fr);
    column-gap: 1.5rem;
  }
  .step__n { grid-row: 1 / span 2; padding-top: 0.45rem; }
}

/* Privacy: the removal address, set large enough to tap */
.email-link {
  display: inline-flex;
  align-items: center;
  min-height: 2.875rem;
  color: var(--ink);
  font-family: var(--serif);
  font-size: var(--fs-h3);
  overflow-wrap: anywhere;
}

/* Model history (2026-10-07) -------------------------------------------------
   Built from existing parts: the page head, margin-column sections, .steps,
   .facts, .areas, the level glyphs and one tinted band. Only four small
   additions follow: the timeline's dates, Table 1, the kept/changed columns
   and one pull statement. */

/* The CMM timeline is a .steps list. Its dates are set in the serif, like
   the area numerals, without the uppercase label treatment (which would
   print "1980S"); they stay small, so the levels keep the only big numerals. */
.timeline .step__n {
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.15rem;
  font-weight: 500;
  letter-spacing: 0;
  text-transform: none;
  font-variant-numeric: lining-nums;
}
@media (min-width: 48em) {
  .timeline .step { grid-template-columns: 8rem minmax(0, 1fr); }
  .timeline .step__n { padding-top: 0.2rem; }
}

/* Table 1: CMM's five levels beside the SOM Institute's six. The level
   column repeats the mark: an empty ring at 0, the amber sun at 5, a
   meridian line through every glyph (as on the model page's ladders). */
.compare {
  width: 100%;
  margin-top: 2.5rem;
  border-collapse: collapse;
  border-top: 2px solid var(--ink);
}
.compare th,
.compare td {
  padding: 0.85rem 1rem 0.95rem 0;
  border-bottom: 1px solid var(--rule);
  text-align: left;
  vertical-align: top;
}
.compare thead th {
  padding-block: 0.75rem;
  color: var(--muted);
  font-size: var(--fs-label);
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.compare tbody td {
  padding-top: calc(0.85rem + 0.7rem);   /* centres a first line on the glyph */
  font-family: var(--serif);
  font-size: 1.2rem;
  line-height: 1.3;
}
.compare__lvl { position: relative; width: 4rem; }
.compare__lvl::before {
  content: "";
  position: absolute;
  left: calc(1.5rem - 0.5px);
  top: 0;
  bottom: 0;
  border-left: 1px solid var(--ink);
}
.compare tbody tr:first-child .compare__lvl::before { top: calc(0.85rem + 1.5rem); }
.compare tbody tr:last-child .compare__lvl::before { bottom: auto; height: calc(0.85rem + 1.5rem); }
.compare__none { color: var(--muted); }
.compare caption {
  caption-side: bottom;
  margin-top: 0;          /* the last row's hairline is the caption's rule */
  border-top: 0;
  text-align: left;
}

/* What was kept and what changed: two ruled columns */
.kc { display: grid; gap: 2.5rem; margin-top: 3rem; }
.kc__title { padding-top: 1rem; border-top: 2px solid var(--ink); }
.kc__list { margin-top: 0.5rem; padding: 0; list-style: none; }
.kc__list li {
  padding-block: 0.85rem 0.95rem;
  border-bottom: 1px solid var(--rule);
  color: var(--ink-2);
}
.kc__list strong { color: var(--ink); }
@media (min-width: 48em) {
  .kc {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(2rem, 1rem + 3vw, 4rem);
  }
}

/* One pull statement, set like the survey's anatomy line, under a navy rule */
.pull {
  max-width: 32ch;
  margin-top: 2.5rem;
  padding-top: 1rem;
  border-top: 2px solid var(--ink);
  font-family: var(--serif);
  font-size: var(--fs-lede);
  font-style: italic;
  line-height: 1.35;
}


/* 7 CLOSING BAND & FOOTER ================================================== */

.coda {
  position: relative;
  overflow: hidden;
  padding-block: clamp(4rem, 2.5rem + 6vw, 8rem);
  background: var(--night);
  color: var(--night-ink);
}
.coda__inner { position: relative; z-index: 1; }
.coda__title {
  max-width: 17ch;
  margin-top: 1.2rem;
  font-size: var(--fs-h1);
}
.coda__text {
  max-width: 34rem;
  margin-top: 1.4rem;
  color: var(--night-muted);
  font-family: var(--serif);
  font-size: var(--fs-lede);
  line-height: 1.42;
}
.coda .cta { margin-top: 2.25rem; }
.coda__art { display: none; }
@media (min-width: 48em) {
  .coda__art {
    display: block;
    position: absolute;
    right: 0;
    bottom: -3rem;
    width: min(40rem, 50%);
    height: auto;
    color: var(--night-rule);
    pointer-events: none;
  }
}

.site-footer {
  /* below 60em the bottom padding keeps the last line clear of the folio */
  padding-block: clamp(3rem, 2rem + 3vw, 4.5rem) calc(var(--folio-h) + 2.5rem + env(safe-area-inset-bottom, 0px));
  border-top: 1px solid var(--night-rule);
  background: var(--night);
  color: var(--night-muted);
  font-size: var(--fs-small);
}
.site-footer a { color: var(--night-ink); }
.footer__grid { display: grid; gap: 2.25rem; }
.footer__brand .brand { color: var(--night-ink); }
.footer__brand .brand__mark { --mark-ground: var(--night); }
.footer__brand .brand__full { color: var(--night-muted); }
.footer__tagline { max-width: 22rem; margin-top: 0.85rem; }
.footer__h {
  margin-bottom: 0.6rem;
  color: var(--night-muted);
  font-family: var(--sans);
  font-size: var(--fs-label);
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.footer__list { padding: 0; list-style: none; }
.footer__list a {
  display: inline-flex;
  align-items: center;
  min-height: 2.875rem;
  text-decoration: none;
}
.footer__list a:hover { text-decoration: underline; }
.footer__text > * + * { margin-top: 0.75rem; }
.footer__email {
  display: inline-flex;
  align-items: center;
  min-height: 2.875rem;
  overflow-wrap: anywhere;
}
/* The colophon: the model's ownership and the benchmark partners in the
   brief's short form. The four names share one colour, so none is billed
   above the others; each keeps its separator when the line wraps. */
.footer__credits {
  margin-top: 2.75rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--night-rule);
}
.footer__credit { white-space: nowrap; }
.footer__credits [data-partner] { color: var(--night-ink); }
.footer__base {
  display: flex;
  flex-wrap: wrap;
  row-gap: 0.25rem;
  margin-top: 0.6rem;
  padding: 0;
  list-style: none;
  font-size: 0.875rem;
}
.footer__base li { white-space: nowrap; }
.footer__base li:not(:last-child)::after {
  content: "\00B7";
  content: "\00B7" / "";
  margin-inline: 0.6em;
}
@media (min-width: 48em) {
  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 60em) {
  .site-footer { padding-bottom: clamp(3rem, 2rem + 3vw, 4.5rem); }
  .footer__grid {
    grid-template-columns: 1.5fr 1fr 1.3fr;
    column-gap: 2.5rem;
  }
}


/* 8 MOTION & PRINT ========================================================= */

/* The hero figure draws itself once: the arc rises from the horizon and the
   levels arrive in order, the sun last. Only for people who have not asked
   their system for reduced motion; everyone else sees the finished figure. */
@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }

  .mfig--animate .mfig__arc {
    stroke-dasharray: 100;
    stroke-dashoffset: 100;
    animation: mfig-draw 1.5s linear 0.15s forwards;
  }
  .mfig--animate .mfig__guides {
    opacity: 0;
    animation: mfig-fade 0.8s ease 1.2s forwards;
  }
  .mfig--animate .mfig__node,
  .mfig--animate .mfig__halo,
  .mfig--animate .mfig__labels text {
    opacity: 0;
    transform-box: fill-box;
    transform-origin: center;
    animation: mfig-pop 0.5s cubic-bezier(0.3, 1.35, 0.5, 1) forwards;
  }
  .mfig--animate .mfig__node--0, .mfig--animate .mfig__labels text:nth-child(1) { animation-delay: 0.15s; }
  .mfig--animate .mfig__node--1, .mfig--animate .mfig__labels text:nth-child(2) { animation-delay: 0.45s; }
  .mfig--animate .mfig__node--2, .mfig--animate .mfig__labels text:nth-child(3) { animation-delay: 0.75s; }
  .mfig--animate .mfig__node--3, .mfig--animate .mfig__labels text:nth-child(4) { animation-delay: 1.05s; }
  .mfig--animate .mfig__node--4, .mfig--animate .mfig__labels text:nth-child(5) { animation-delay: 1.35s; }
  .mfig--animate .mfig__node--5, .mfig--animate .mfig__labels text:nth-child(6) { animation-delay: 1.65s; }
  .mfig--animate .mfig__halo { animation-delay: 1.9s; }
}
@keyframes mfig-draw { to { stroke-dashoffset: 0; } }
@keyframes mfig-fade { to { opacity: 1; } }
@keyframes mfig-pop {
  from { opacity: 0; transform: scale(0.3); }
  to   { opacity: 1; transform: none; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

@media print {
  .masthead, .skip-link, .nav__item--cta, .onpage, .coda__art, [data-survey] { display: none !important; }
  body { padding-top: 0 !important; background: #fff; color: #000; }
  .coda, .site-footer { background: #fff !important; color: #000 !important; }
  .coda *, .site-footer * { color: #000 !important; }
  .section__aside, .area__head { position: static !important; }
}