/* ==========================================================================
   A case study (/blog/<slug>, type case_study) — "the feature". Set like a magazine story, deliberately unlike the
   article's reading room: an ink opener with a spec sheet, the hero pulled across the ink edge, the engagement in
   figures, a chapter pill that follows the reader, four chapters each with its own spread (giant numerals, a drop
   cap, a cinematic picture, newspaper columns, a drawn timeline, a build sheet), a picture essay on ink with a
   lightbox, results set big, and the way in. Loaded after hub.css, kit.css, blocks.css and blog.css.
   core.css tokens only: no colour literals, no gradients except mask fades, no !important.
   ========================================================================== */
.bcs{--bcs-pull:clamp(72px,11vw,190px);--bcs-measure:680px}

/* ---------- the opener (ink) --------------------------------------------- */
.bcs-cover{padding-top:var(--bdh-hero-t);padding-bottom:calc(clamp(48px,5vw,80px) + var(--bcs-pull))}
.bcs-cover--plain{padding-bottom:clamp(56px,6vw,96px)}
.bcs-cover__top{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 24px;padding-bottom:18px;border-bottom:1px solid var(--on-ink-line)}
.bcs-cover__no{display:flex;flex-wrap:wrap;align-items:center;gap:6px 16px;font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--on-ink)}
.bcs-cover__no span{color:var(--on-ink-3)}
.bcs-cover__no span:first-child{color:var(--on-ink)}
.bcs-cover__min{padding-left:16px;border-left:1px solid var(--on-ink-line)}
.bcs-cover__t{max-width:19ch;margin-top:clamp(36px,4.6vw,72px);font-family:var(--f-h);font-size:clamp(2.2rem,5.6vw,5rem);font-weight:500;line-height:1;letter-spacing:-.036em;color:var(--on-ink);text-wrap:balance}
.bcs-cover__low{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:32px;align-items:start;margin-top:clamp(30px,3.6vw,52px)}
.bcs-cover__dek{grid-column:1 / span 6;font-size:clamp(1.02rem,1.3vw,1.2rem);line-height:1.62;color:var(--on-ink-2)}
.bcs-spec{grid-column:8 / 13;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));grid-auto-flow:row dense;border-top:1px solid var(--on-ink)}
.bcs-spec__i{display:flex;flex-direction:column;gap:8px;padding:14px 16px 14px 0;border-bottom:1px solid var(--on-ink-line);min-width:0}
.bcs-spec__i--client,.bcs-spec__i--disc{grid-column:1 / -1}
.bcs-spec dt{font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.14em;text-transform:uppercase;color:var(--on-ink-3)}
.bcs-spec dd{font-size:var(--t-sm);font-weight:500;line-height:1.5;color:var(--on-ink)}
.bcs-spec a{color:var(--on-ink);text-decoration:underline;text-decoration-color:var(--on-ink-line);text-underline-offset:3px;transition:text-decoration-color var(--d1) var(--e-io)}
.bcs-spec a:hover{text-decoration-color:var(--on-ink)}
.bcs-spec__list{display:flex;flex-wrap:wrap;gap:4px 16px}
.bcs-spec__list li{display:inline-flex;align-items:center;gap:.55em}
.bcs-spec__list li::before{content:"";width:5px;height:5px;border-radius:50%;background:var(--blue)}

/* the hero, pulled up across the ink edge */
.bcs-lede{position:relative;z-index:1}
.bcs-hero{width:min(100% - (var(--gutter) * 2),1440px);margin:calc(-1 * var(--bcs-pull)) auto 0}
.bcs-hero__box{overflow:hidden;aspect-ratio:21 / 9;border-radius:var(--r-xl);background:var(--ink-2);box-shadow:var(--sh-2)}
.bcs-hero__box picture{display:contents}
.bcs-hero__img{display:block;width:100%;height:100%;object-fit:cover}
.bcs-hero__cap{display:flex;flex-wrap:wrap;justify-content:space-between;gap:6px 24px;width:min(100%,var(--wrap));margin:12px auto 0;font-size:var(--t-xs);line-height:1.55;color:var(--muted)}
.bcs-hero__credit{color:var(--faint)}
.bcs-hero__credit a{color:inherit;text-decoration:underline;text-decoration-color:var(--line-3);text-underline-offset:3px}

/* the engagement in figures (scope, never results) */
.bcs-facts{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:18px;margin-top:clamp(44px,5vw,80px)}
.bcs-facts__t{grid-column:1 / span 3;padding-top:20px;font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--ink);line-height:1.6}
.bcs-facts__list{grid-column:4 / 13;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:0 var(--bdh-gap)}
.bcs-facts__list--1{grid-template-columns:minmax(0,1fr)}
.bcs-facts__list--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.bcs-facts__list--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.bcs-facts__i{display:flex;flex-direction:column;gap:10px;padding-top:16px;border-top:2px solid var(--ink)}
.bcs-facts__i dd{order:-1;font-family:var(--f);font-size:clamp(2.2rem,4.4vw,3.8rem);font-weight:400;line-height:1;letter-spacing:-.05em;color:var(--ink);font-variant-numeric:tabular-nums}
.bcs-facts__i dt{max-width:22ch;font-size:var(--t-sm);line-height:1.5;color:var(--txt)}

/* ---------- the story in chapters: the contents panel under the opener (never floats over the text) ---- */
.bcs-story{position:relative}
.bcs-toc{padding-top:clamp(52px,5.6vw,92px)}
.bcs-toc__head{display:flex;flex-wrap:wrap;align-items:baseline;justify-content:space-between;gap:6px 24px;padding-bottom:14px;border-bottom:1px solid var(--ink)}
.bcs-toc__t{font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--ink)}
.bcs-toc__m{font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.14em;text-transform:uppercase;color:var(--muted)}
.bcs-toc__list{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));border-bottom:1px solid var(--line-3)}
.bcs-toc__list--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.bcs-toc__list--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.bcs-toc__it{min-width:0;border-right:1px solid var(--line-3)}
.bcs-toc__it:last-child{border-right:0}
.bcs-toc__a{display:flex;flex-direction:column;gap:10px;height:100%;padding:clamp(18px,2vw,26px) clamp(16px,2vw,28px) clamp(22px,2.4vw,30px);color:inherit;transition:background var(--d2) var(--e)}
.bcs-toc__it:first-child .bcs-toc__a{padding-left:0}
.bcs-toc__a:hover{background:var(--paper-2)}
.bcs-toc__it:first-child .bcs-toc__a:hover{background:none}
.bcs-toc__n{font-family:var(--f-h);font-size:clamp(2.2rem,3.4vw,3rem);font-weight:500;line-height:.9;letter-spacing:-.05em;color:var(--ghost);font-variant-numeric:tabular-nums;transition:color var(--d2) var(--e)}
.bcs-toc__a:hover .bcs-toc__n,.bcs-toc__a:focus-visible .bcs-toc__n,.bcs-toc__a.is-on .bcs-toc__n{color:var(--blue)}
.bcs-toc__l{font-family:var(--f-h);font-size:clamp(1.05rem,1.3vw,1.22rem);font-weight:500;line-height:1.25;color:var(--ink)}
.bcs-toc__a:hover .bcs-toc__l{text-decoration:underline;text-decoration-color:var(--blue-line);text-underline-offset:4px}
.bcs-toc__x{font-size:var(--t-sm);line-height:1.55;color:var(--txt)}

/* reading aids case.js adds: a chapter strip on the window's top edge, and at wide screens a chapter index in the
   right-hand margin (numbers; the name slides out on hover). Both are aria-hidden: the panel above is the navigation. */
.bcs-strip{position:fixed;top:0;left:0;right:0;z-index:95;display:flex;gap:3px;height:3px;padding:0 3px;pointer-events:none;opacity:0;transition:opacity var(--d2) var(--e)}
.bcs-strip.is-on{opacity:1}
.bcs-strip i{position:relative;flex:1;overflow:hidden;border-radius:0 0 2px 2px;background:var(--line-2)}
.bcs-strip b{position:absolute;inset:0;background:var(--blue);transform:scaleX(0);transform-origin:0 50%}
.bcs-strip i.is-past b{background:var(--ink);transform:none}
.bcs-gut{display:none}
@media (min-width:1240px){
  .bcs-gut{position:fixed;z-index:79;right:clamp(4px,calc((100vw - var(--wrap)) / 2 - 62px),40px);top:50%;display:flex;flex-direction:column;gap:2px;padding:6px 0;
    border:1px solid var(--line);border-radius:var(--r-pill);background:var(--paper);box-shadow:var(--sh-1);transform:translateY(-50%);opacity:0;pointer-events:none;transition:opacity .35s var(--e)}
  .bcs-gut.is-on{opacity:1;pointer-events:auto}
  .bcs-gut a{position:relative;display:grid;place-items:center;width:40px;height:44px;font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.06em;color:var(--faint);transition:color .25s var(--e)}
  .bcs-gut a::before{content:"";position:absolute;right:6px;top:50%;width:2px;height:0;border-radius:2px;background:var(--blue);transform:translateY(-50%);transition:height .35s var(--e)}
  .bcs-gut a:hover,.bcs-gut a.is-on{color:var(--ink)}
  .bcs-gut a.is-on::before{height:18px}
  .bcs-gut a.is-past{color:var(--muted)}
  .bcs-gut span{position:absolute;right:calc(100% + 10px);top:50%;padding:6px 12px;border-radius:var(--r-pill);background:var(--ink);color:var(--on-ink);white-space:nowrap;
    font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.1em;text-transform:uppercase;opacity:0;pointer-events:none;transform:translate(6px,-50%);transition:opacity .2s var(--e),transform .2s var(--e)}
  .bcs-gut a:hover span{opacity:1;transform:translate(0,-50%)}
}

/* ---------- chapters ------------------------------------------------------ */
.bcs-story > .bcs-ch:first-of-type{padding-top:clamp(48px,5vw,80px)}
.bcs-ch__head{display:grid;grid-template-columns:auto minmax(0,1fr);align-items:end;column-gap:clamp(18px,2.6vw,40px);padding-bottom:clamp(18px,2vw,26px);margin-bottom:clamp(36px,4.4vw,64px);border-bottom:1px solid var(--ink)}
.bcs-ch__no{font-family:var(--f-h);font-size:clamp(4.6rem,11vw,9.6rem);font-weight:500;line-height:.74;letter-spacing:-.06em;color:var(--ghost);font-variant-numeric:tabular-nums;user-select:none}
.band--alt .bcs-ch__no{color:var(--line-3)}
.bcs-ch__id{display:flex;flex-direction:column;gap:14px;min-width:0;padding-bottom:4px}
.bcs-ch__lbl{font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--blue-d)}
.bcs-ch__t{font-family:var(--f-h);font-size:var(--t-h2);font-weight:500;line-height:1.04;letter-spacing:-.03em;color:var(--ink)}

/* the brief, set large */
.bcs-brief{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:12px;margin-bottom:clamp(40px,4.6vw,72px)}
.bcs-brief__k{grid-column:1 / span 3;padding-top:.7em;font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--muted)}
.bcs-brief__q{grid-column:4 / 13;max-width:30ch;font-family:var(--f-h);font-size:clamp(1.45rem,2.7vw,2.35rem);font-weight:500;line-height:1.16;letter-spacing:-.024em;color:var(--ink);text-wrap:balance}
.bcs-brief__q::before{content:"\201C";margin-right:.04em;color:var(--blue)}
.bcs-brief__q::after{content:"\201D";color:var(--blue)}

/* spreads: text + picture */
.bcs-spread{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:36px;align-items:start}
.bcs-spread__text{grid-column:1 / span 7;min-width:0}
.bcs-spread__fig{grid-column:9 / 13;position:sticky;top:calc(var(--nav-h) + 92px)}
.bcs-spread--flip .bcs-spread__fig{grid-column:1 / span 6;position:static}
.bcs-spread--flip .bcs-spread__text{grid-column:8 / 13}
.bcs-spread--solo .bcs-spread__text,.bcs-spread--flip.bcs-spread--solo .bcs-spread__text{grid-column:1 / span 8}

/* chapter prose */
.bcs-prose{--xb-measure:var(--bcs-measure);max-width:var(--bcs-measure);margin-inline:0}
.bcs-prose .xb-p,.bcs-prose .xb-list{font-size:clamp(1.02rem,1.08vw,1.09rem);line-height:1.78;color:var(--txt)}
.bcs-prose .xb-h3,.bcs-prose .xb-h4{margin-top:1.8em;font-size:clamp(1.12rem,1.4vw,1.3rem);line-height:1.25;letter-spacing:-.014em}
.bcs-prose .xb-md > .xb-h3:first-child{margin-top:0}
.bcs-drop .xb-md > .xb-p:first-child::first-letter{float:left;margin:.06em .1em 0 -.02em;font-family:var(--f-h);font-size:4.35em;font-weight:500;line-height:.78;letter-spacing:-.04em;color:var(--ink)}

/* pictures */
.bcs-fig{margin:0}
.bcs-fig__box{position:relative;overflow:hidden;border-radius:var(--r-lg);background:var(--paper-3)}
.bcs-fig__box picture{display:contents}
.bcs-fig__img{display:block;width:100%;height:100%;object-fit:cover}
.bcs-fig--tall .bcs-fig__box{aspect-ratio:4 / 5}
.bcs-fig--land .bcs-fig__box{aspect-ratio:4 / 3}
.bcs-fig--cine{margin-bottom:clamp(40px,4.6vw,72px)}
.bcs-fig--cine .bcs-fig__box{aspect-ratio:21 / 9;border-radius:var(--r-xl)}
/* the picture is 52px taller than its frame so BDH.parallax can drift it ±24px without showing an edge */
.bcs-fig--cine .bcs-fig__box[data-bdh-parallax] > :is(img,picture){display:block;position:absolute;left:0;right:0;top:-26px;width:100%;height:calc(100% + 52px)}
.bcs-fig--cine .bcs-fig__box[data-bdh-parallax] > picture img{height:100%}
.bcs-fig__cap{display:flex;flex-wrap:wrap;justify-content:space-between;gap:4px 18px;margin-top:12px;font-size:var(--t-xs);line-height:1.55;color:var(--muted)}
.bcs-fig__credit{color:var(--faint)}
.bcs-fig__credit a{color:inherit;text-decoration:underline;text-decoration-color:var(--line-3);text-underline-offset:3px}
.bcs-fig__credit a:hover{color:var(--ink)}

/* newspaper columns (chapter 02) */
.bcs-cols .bcs-prose{max-width:none}
@media (min-width:1101px){
  .bcs-cols{columns:2;column-gap:var(--bdh-gap-l);column-rule:1px solid var(--line)}
  .bcs-cols .xb-md > *{break-inside:avoid-column}
  .bcs-cols .xb-h{break-after:avoid}
}

/* ---------- the process timeline ----------------------------------------- */
.bcs-tl{margin-top:clamp(56px,6vw,96px)}
.bcs-tl__head{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:10px;align-items:end;margin-bottom:clamp(28px,3vw,44px)}
.bcs-tl__h{grid-column:1 / span 5;font-family:var(--f-h);font-size:clamp(1.3rem,2vw,1.75rem);font-weight:500;line-height:1.15;letter-spacing:-.02em;color:var(--ink)}
.bcs-tl__lead{grid-column:8 / 13;font-size:var(--t-sm);line-height:1.6;color:var(--muted)}
.bcs-tl__list{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));column-gap:0;row-gap:clamp(30px,3vw,44px)}
.bcs-tl__list--1{grid-template-columns:minmax(0,1fr)}
.bcs-tl__list--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.bcs-tl__list--3,.bcs-tl__list--6{grid-template-columns:repeat(3,minmax(0,1fr))}
.bcs-tl__list--5{grid-template-columns:repeat(5,minmax(0,1fr))}
.bcs-tl__it{position:relative;display:flex;flex-direction:column;gap:10px;padding:30px clamp(14px,1.6vw,26px) 0 0;min-width:0}
.bcs-tl__it::before{content:"";position:absolute;left:0;right:0;top:7px;height:1px;background:var(--ink);transform-origin:0 50%}
.bcs-tl__dot{position:absolute;left:0;top:0;width:15px;height:15px;border-radius:50%;background:var(--paper-2);border:2px solid var(--blue)}
.bcs-tl__it:last-child .bcs-tl__dot{background:var(--blue)}
.bcs-tl__k{display:flex;flex-wrap:wrap;align-items:baseline;gap:4px 12px;font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.14em;text-transform:uppercase;color:var(--muted)}
.bcs-tl__n{color:var(--blue-d)}
.bcs-tl__when{color:var(--ink)}
.bcs-tl__t{font-family:var(--f-h);font-size:var(--t-h3);font-weight:500;line-height:1.28;letter-spacing:-.012em;color:var(--ink)}
.bcs-tl__x{font-size:var(--t-sm);line-height:1.6;color:var(--txt)}
/* the line draws itself in (case.js adds .is-anim at load, .is-in on entry); the HTML alone is the finished timeline */
.bcs-tl.is-anim .bcs-tl__it::before{transform:scaleX(0);transition:transform .9s var(--e) calc(var(--i,0) * .16s)}
.bcs-tl.is-anim .bcs-tl__dot{transform:scale(0);transition:transform .5s var(--e) calc(var(--i,0) * .16s + .1s)}
.bcs-tl.is-anim.is-in .bcs-tl__it::before{transform:none}
.bcs-tl.is-anim.is-in .bcs-tl__dot{transform:none}
/* only the line and the stops move: the words are always there, even if the timeline is never scrolled to */

/* ---------- the system, as people see it (chapter 03): an illustrative screen drawn from the entry ---------- */
.bcs-sys{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:28px;align-items:center;margin-top:clamp(56px,6vw,96px);
  padding:clamp(24px,3.4vw,52px);border:1px solid var(--line);border-radius:var(--r-xl);background:var(--paper-2)}
.bcs-sys__copy{grid-column:1 / span 4;display:flex;flex-direction:column;align-items:flex-start;gap:14px}
.bcs-sys__lead{max-width:38ch;font-size:var(--t-sm);line-height:1.65;color:var(--txt)}
.bcs-sys__key{display:flex;flex-direction:column;gap:9px;margin-top:4px}
.bcs-sys__key li{display:flex;align-items:center;gap:10px;font-size:var(--t-xs);color:var(--muted)}
.bcs-sys__fig{grid-column:6 / 13;min-width:0;margin:0}
.bcs-sys__note{margin-top:12px;font-size:var(--t-xs);line-height:1.55;color:var(--muted)}
.bcs-sys__ui{border-radius:var(--r-lg)}
.bcs-sys__title{min-width:0;overflow:hidden;text-overflow:ellipsis}
.bcs-sys__mark{display:inline-grid;place-items:center;flex:none;width:22px;height:22px;border-radius:50%}
.bcs-sys__mark svg{width:14px;height:14px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.bcs-sys__mark.is-ok{background:var(--ink);color:var(--on-ink)}
.bcs-sys__mark.is-flag{background:var(--blue);color:var(--on-ink)}
.bcs-sys__mark.is-person{background:var(--paper);color:var(--ink);box-shadow:inset 0 0 0 1.5px var(--ink)}
.bcs-sys__mark.is-now{background:var(--blue-wash-2);color:var(--blue-d)}
.bcs-sys__mark.is-info{background:var(--paper-3);color:var(--muted)}
/* checks */
.bcs-sys__row{display:grid;grid-template-columns:22px minmax(0,1fr) auto;column-gap:12px;row-gap:3px;align-items:center;padding:13px 18px;border-bottom:1px solid var(--line-2)}
.bcs-sys__row:last-child{border-bottom:0}
.bcs-sys__l{min-width:0;font-size:var(--t-sm);font-weight:500;line-height:1.4;color:var(--ink)}
.bcs-sys__w{font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.1em;text-transform:uppercase;color:var(--muted);white-space:nowrap}
.bcs-sys__row.is-flag .bcs-sys__w{color:var(--blue-d)}
.bcs-sys__d{grid-column:2 / -1;font-size:var(--t-xs);line-height:1.5;color:var(--txt)}
.bcs-sys--checks .bcs-sys__row.is-flag{background:var(--blue-wash)}
.bcs-sys__foot{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 16px;padding:14px 18px;border-top:1px solid var(--line);background:var(--paper-2)}
.bcs-sys__who{display:inline-flex;align-items:center;gap:9px;font-size:var(--t-xs);font-weight:500;color:var(--ink)}
.bcs-sys__btns{display:inline-flex;gap:8px}
.bcs-sys__btn{display:inline-flex;align-items:center;height:32px;padding:0 14px;border:1px solid var(--line-3);border-radius:var(--r-pill);background:var(--paper);font-size:var(--t-xs);font-weight:500;color:var(--ink)}
.bcs-sys__btn.is-go{border-color:var(--ink);background:var(--ink);color:var(--on-ink)}
/* a conversation */
.bcs-sys--chat .bcs-sys__rows{display:flex;flex-direction:column;gap:14px;padding:20px 18px}
.bcs-sys__msg{display:flex;flex-direction:column;align-items:flex-start;gap:6px;max-width:86%}
.bcs-sys__msg.is-info{align-self:flex-end;align-items:flex-end}
.bcs-sys__bub{padding:10px 14px;border-radius:16px 16px 16px 6px;background:var(--paper-3);font-size:var(--t-sm);line-height:1.5;color:var(--ink)}
.bcs-sys__msg.is-info .bcs-sys__bub{border-radius:16px 16px 6px 16px;background:var(--ink);color:var(--on-ink)}
.bcs-sys__msg.is-person .bcs-sys__bub{background:var(--blue-wash)}
.bcs-sys__msg.is-flag .bcs-sys__bub{background:var(--paper);box-shadow:inset 0 0 0 1px var(--line-3)}
.bcs-sys__meta{display:inline-flex;align-items:center;gap:7px;font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.06em;line-height:1.4;color:var(--muted)}
.bcs-sys__meta .bcs-sys__mark{width:18px;height:18px}
.bcs-sys__meta .bcs-sys__mark svg{width:12px;height:12px}
/* steps on a phone */
.bcs-sys--steps .bcs-sys__fig{display:flex;flex-direction:column;align-items:center}
.bcs-sys--steps .bcs-sys__note{max-width:46ch;text-align:center}
.bcs-sys__phone{position:relative;width:min(100%,340px);padding:46px 20px 18px;border:1px solid var(--line-3);border-radius:40px;background:var(--paper);box-shadow:var(--sh-2)}
.bcs-sys__notch{position:absolute;left:50%;top:13px;width:84px;height:22px;border-radius:12px;background:var(--ink);transform:translateX(-50%)}
.bcs-sys__ptitle{font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.14em;text-transform:uppercase;color:var(--muted)}
.bcs-sys__prog{display:flex;gap:4px;margin-top:12px}
.bcs-sys__prog i{flex:1;height:4px;border-radius:2px;background:var(--line-2)}
.bcs-sys__prog i.is-ok{background:var(--ink)}
.bcs-sys__prog i.is-now{background:var(--blue)}
.bcs-sys__pstep{margin-top:18px;font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.12em;text-transform:uppercase;color:var(--blue-d)}
.bcs-sys__pnow{margin-top:6px;font-family:var(--f-h);font-size:1.32rem;font-weight:500;line-height:1.2;letter-spacing:-.012em;color:var(--ink)}
.bcs-sys__pdet{margin-top:8px;font-size:var(--t-xs);line-height:1.6;color:var(--txt)}
.bcs-sys--steps .bcs-sys__rows{margin-top:16px;border-top:1px solid var(--line)}
.bcs-sys--steps .bcs-sys__row{padding:11px 2px}
.bcs-sys--steps .bcs-sys__row.is-now{background:none}
.bcs-sys--steps .bcs-sys__row.is-now .bcs-sys__l{color:var(--blue-d)}
.bcs-sys--steps .bcs-sys__row.is-info .bcs-sys__l{color:var(--muted);font-weight:400}
/* played in by case.js once on screen (it adds .is-anim, then .is-in); the HTML alone is the finished screen */
.bcs-sys.is-anim :is(.bcs-sys__row,.bcs-sys__msg){opacity:0;transform:translateY(8px);transition:opacity .45s var(--e) calc(var(--i,0) * .32s + .2s),transform .45s var(--e) calc(var(--i,0) * .32s + .2s)}
.bcs-sys.is-anim.is-in :is(.bcs-sys__row,.bcs-sys__msg){opacity:1;transform:none}
.bcs-sys.is-anim .bcs-sys__prog i{transform:scaleX(0);transform-origin:0 50%;transition:transform .5s var(--e) .3s}
.bcs-sys.is-anim.is-in .bcs-sys__prog i{transform:none}

/* ---------- the build sheet (chapter 03) --------------------------------- */
.bcs-sheet{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:44px;align-items:start;margin-top:clamp(56px,6vw,96px);padding-top:clamp(28px,3vw,40px);border-top:1px solid var(--line-3)}
.bcs-sheet__del{grid-column:1 / span 7}
.bcs-sheet__side{grid-column:9 / 13;display:flex;flex-direction:column;gap:36px}
.bcs-sheet--nodel .bcs-sheet__side{grid-column:1 / -1;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));column-gap:var(--bdh-gap-l)}
.bcs-sheet__h{margin-bottom:16px;font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--ink)}
.bcs-sheet__note{margin-top:12px;font-size:var(--t-xs);line-height:1.55;color:var(--muted)}
.bcs-del{display:flex;flex-direction:column;border-top:1px solid var(--ink)}
.bcs-del__it{display:grid;grid-template-columns:52px minmax(0,1fr);align-items:baseline;gap:12px;padding:18px 0;border-bottom:1px solid var(--line-3)}
.bcs-del__n{font-family:var(--f);font-size:var(--t-sm);color:var(--blue-d);font-variant-numeric:tabular-nums}
.bcs-del__t{font-family:var(--f-h);font-size:clamp(1.12rem,1.65vw,1.45rem);font-weight:500;line-height:1.25;letter-spacing:-.016em;color:var(--ink)}
.bcs-std{display:flex;flex-wrap:wrap;gap:8px}
.bcs-stack.xt-stack{gap:8px}

/* the story, continued */
.bcs-more{max-width:var(--bcs-measure);margin:clamp(56px,6vw,96px) auto 0}
.bcs-more__lbl{margin-bottom:22px}
.bcs-more__x{margin-inline:auto}
.bcs-prose .xb-quote{margin-block:2.2em;padding:clamp(22px,2.4vw,30px) 0;border-left:0;border-block:1px solid var(--ink)}
.bcs-prose .xb-quote__q p{font-size:clamp(1.35rem,2.3vw,1.9rem);line-height:1.22;letter-spacing:-.022em;color:var(--ink);text-wrap:balance}
.bcs-prose .xb-img img,.bcs-prose .xb-gal img{border-radius:var(--r-lg)}
.bcs-prose .xb-call{border-radius:var(--r-lg)}
.bcs-prose .xb-call__t{line-height:1.3}
.bcs-prose .xb-call--warn,.bcs-prose .xb-call--success{border-radius:0 var(--r-lg) var(--r-lg) 0}
.bcs-prose .xb-stats{border:1px solid var(--line);border-radius:var(--r-lg);padding-inline:clamp(18px,2.2vw,28px);background:var(--paper-2)}

/* ---------- the picture essay (ink) --------------------------------------- */
.bcs-gallery__hint{max-width:40ch}
.bcs-gal{display:grid;grid-template-columns:minmax(0,1fr);gap:clamp(14px,1.6vw,22px)}
.bcs-gal__it{display:flex;min-width:0}
/* desktop: the lead picture takes four columns and six rows, the next two stack beside it, the rest run three to a
   row; a last picture alone spans the row and a last pair halves it */
@media (min-width:861px){
  .bcs-gal{grid-template-columns:repeat(6,minmax(0,1fr));grid-auto-rows:clamp(50px,5.4vw,78px)}
  .bcs-gal__it{grid-column:span 2;grid-row:span 4}
  .bcs-gal__it:nth-child(1){grid-column:span 4;grid-row:span 6}
  .bcs-gal__it:nth-child(2),.bcs-gal__it:nth-child(3){grid-row:span 3}
  .bcs-gal--1 .bcs-gal__it:nth-child(1){grid-column:span 6;grid-row:span 7}
  .bcs-gal--2 .bcs-gal__it:nth-child(2){grid-row:span 6}
  .bcs-gal__it:nth-child(3n+4):last-child{grid-column:span 6;grid-row:span 6}
  .bcs-gal__it:nth-child(3n+4):nth-last-child(2),.bcs-gal__it:nth-child(3n+4):nth-last-child(2) + .bcs-gal__it{grid-column:span 3;grid-row:span 5}
}
.bcs-gal__fig{display:flex;flex-direction:column;width:100%;min-height:0;margin:0}
.bcs-gal__a{position:relative;display:block;flex:1;min-height:0;overflow:hidden;border-radius:var(--r-lg);background:var(--on-ink-card);cursor:zoom-in}
.bcs-gal__a picture{display:contents}
.bcs-gal__img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;transition:transform 1.1s var(--e),opacity var(--d2) var(--e)}
.bcs-gal__a:hover .bcs-gal__img{transform:scale(1.035)}
.bcs-gal__a:focus-visible{outline:2px solid var(--blue);outline-offset:3px}
.bcs-gal__zoom{position:absolute;right:12px;top:12px;display:grid;place-items:center;width:38px;height:38px;border-radius:50%;background:var(--ink);color:var(--on-ink);opacity:0;transform:scale(.85);transition:opacity var(--d2) var(--e),transform var(--d2) var(--e)}
.bcs-gal__zoom svg{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}
.bcs-gal__a:hover .bcs-gal__zoom,.bcs-gal__a:focus-visible .bcs-gal__zoom{opacity:1;transform:none}
.bcs-gal__cap{display:grid;grid-template-columns:auto minmax(0,1fr);align-items:baseline;gap:2px 12px;padding-top:10px;font-size:var(--t-xs);line-height:1.5;color:var(--on-ink-2)}
.bcs-gal__no{font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.1em;color:var(--on-ink-3)}
.bcs-gal__txt{min-width:0}
.bcs-gal__cr{grid-column:2;color:var(--on-ink-3)}
.bcs-gal__cr a{color:inherit;text-decoration:underline;text-decoration-color:var(--on-ink-line);text-underline-offset:3px}
.bcs-gal__cr a:hover{color:var(--on-ink)}

/* the lightbox (built by case.js): bar (count · close) / stage / foot (caption, and on wide screens a filmstrip). The
   stage is a definite box and the picture is contained in it, so a portrait, landscape or square picture always fits
   the window whole; the arrows sit in the stage's side margins (wide screens) or beside the caption (phones), never on
   the picture or the words. */
.bcs-lb{position:fixed;inset:0;width:100%;height:100%;max-width:none;max-height:none;margin:0;padding:0;border:0;background:var(--ink);color:var(--on-ink);overflow:hidden}
.bcs-lb::backdrop{background:var(--ink)}
.bcs-lb[open]{display:grid;grid-template-rows:auto minmax(0,1fr) auto}
.bcs-lb__bar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:10px clamp(12px,2.2vw,24px)}
.bcs-lb__count{font-family:var(--f);font-size:var(--t-xs);letter-spacing:.12em;color:var(--on-ink-2);font-variant-numeric:tabular-nums}
.bcs-lb__stage{position:relative;min-width:0;min-height:0;height:100%;padding:0 clamp(68px,7vw,112px);overflow:hidden;touch-action:pan-y}
.bcs-lb__img{display:block;width:100%;height:100%;object-fit:contain;transition:opacity var(--d2) var(--e)}
.bcs-lb__img.is-loading{opacity:.6}
.bcs-lb__foot{display:grid;grid-template-columns:minmax(0,1fr);justify-items:center;gap:12px;padding:12px clamp(16px,3vw,32px) clamp(14px,2vh,22px)}
.bcs-lb__cap{display:flex;flex-wrap:wrap;justify-content:center;gap:2px 16px;max-width:900px;min-height:1.55em;text-align:center;font-size:var(--t-sm);line-height:1.55;color:var(--on-ink-2)}
.bcs-lb__cap a{display:inline-flex;align-items:center;min-height:44px;color:var(--on-ink-3);text-decoration:underline;text-decoration-color:var(--on-ink-line);text-underline-offset:3px}
.bcs-lb__cap a:hover{color:var(--on-ink)}
.bcs-lb__btn{display:inline-grid;place-items:center;width:46px;height:46px;border:1px solid var(--on-ink-line);border-radius:50%;background:var(--on-ink-card);color:var(--on-ink);transition:background var(--d1) var(--e-io),border-color var(--d1) var(--e-io)}
.bcs-lb__btn:hover{background:var(--ink-2);border-color:var(--on-ink-3)}
.bcs-lb__btn:focus-visible{outline:2px solid var(--blue);outline-offset:2px}
.bcs-lb__btn svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.bcs-lb__prev,.bcs-lb__next{position:absolute;top:50%;transform:translateY(-50%)}
.bcs-lb__prev{left:clamp(10px,2vw,30px)}
.bcs-lb__next{right:clamp(10px,2vw,30px)}
.bcs-lb__film{display:flex;gap:8px;max-width:100%;padding:3px;overflow-x:auto;scrollbar-width:none}
.bcs-lb__film::-webkit-scrollbar{display:none}
.bcs-lb__th{flex:none;width:68px;height:46px;padding:0;border:0;border-radius:8px;overflow:hidden;background:var(--on-ink-card);opacity:.5;cursor:pointer;transition:opacity var(--d1) var(--e-io),box-shadow var(--d1) var(--e-io)}
.bcs-lb__th img{display:block;width:100%;height:100%;object-fit:cover}
.bcs-lb__th:hover{opacity:.85}
.bcs-lb__th[aria-current="true"]{opacity:1;box-shadow:0 0 0 2px var(--blue)}
.bcs-lb__th:focus-visible{outline:2px solid var(--on-ink);outline-offset:2px}
@media (max-width:860px){.bcs-lb__film{display:none}}
@media (max-width:600px){
  .bcs-lb__stage{padding:0 10px}
  .bcs-lb__foot{grid-template-columns:46px minmax(0,1fr) 46px;align-items:center;column-gap:12px;padding-inline:12px}
  .bcs-lb__prev,.bcs-lb__next{position:static;transform:none}
  .bcs-lb__prev{grid-column:1;grid-row:1}
  .bcs-lb__cap{grid-column:2;grid-row:1;font-size:var(--t-xs)}
  .bcs-lb__next{grid-column:3;grid-row:1}
}
@media (prefers-reduced-motion:reduce){.bcs-sys :is(.bcs-sys__row,.bcs-sys__msg),.bcs-sys .bcs-sys__prog i,.bcs-lb__img,.bcs-lb__th,.bcs-strip,.bcs-gut,.bcs-gut a,.bcs-gut a::before,.bcs-gut span,.bcs-toc__a,.bcs-toc__n{transition:none}}
html.bcs-lb-on{overflow:hidden}

/* ---------- results (chapter 04) ----------------------------------------- */
.bcs-figs{margin-bottom:clamp(48px,5vw,80px)}
.bcs-figs__h{display:flex;flex-wrap:wrap;align-items:center;gap:10px 16px;margin-bottom:22px;font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--ink)}
.bcs-figs__flag{display:inline-flex;align-items:center;gap:.6em;min-height:28px;padding:4px 12px;border:1px dashed var(--line-3);border-radius:var(--r-pill);background:var(--paper-2);font-size:var(--t-lbl);letter-spacing:.08em;color:var(--muted);text-transform:none;line-height:1.35}
.bcs-figs__list{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:clamp(28px,3vw,44px) var(--bdh-gap)}
.bcs-figs__list--1{grid-template-columns:minmax(0,1fr)}
.bcs-figs__list--2,.bcs-figs__list--4{grid-template-columns:repeat(2,minmax(0,1fr))}
.bcs-figs__it{display:flex;flex-direction:column;gap:10px;padding-top:18px;border-top:2px solid var(--ink)}
.bcs-figs__v{order:-1;font-family:var(--f);font-size:clamp(2.8rem,6.4vw,5.6rem);font-weight:400;line-height:.95;letter-spacing:-.06em;color:var(--ink);font-variant-numeric:tabular-nums}
.bcs-figs.is-pending .bcs-figs__it{border-top-style:dashed}
.bcs-figs__l{max-width:28ch;font-size:var(--t-body);font-weight:500;line-height:1.45;color:var(--ink)}
.bcs-figs__n{font-size:var(--t-xs);line-height:1.55;color:var(--muted)}

.bcs-meas{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:24px;align-items:start;margin-bottom:clamp(48px,5vw,80px)}
.bcs-meas__head{grid-column:1 / span 4;display:flex;flex-direction:column;gap:12px}
.bcs-meas__h{font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.16em;text-transform:uppercase;color:var(--ink)}
.bcs-meas__note{max-width:34ch;font-size:var(--t-sm);line-height:1.6;color:var(--muted)}
.bcs-meas__list{grid-column:5 / 13;display:flex;flex-direction:column;border-top:2px solid var(--ink)}
.bcs-meas__it{display:grid;grid-template-columns:clamp(48px,6vw,84px) minmax(0,1fr);align-items:baseline;gap:12px;padding:clamp(16px,1.8vw,24px) 0;border-bottom:1px solid var(--line-3)}
.bcs-meas__n{font-family:var(--f);font-size:var(--t-sm);color:var(--blue-d);font-variant-numeric:tabular-nums}
.bcs-meas__t{font-family:var(--f-h);font-size:clamp(1.3rem,2.5vw,2.1rem);font-weight:500;line-height:1.14;letter-spacing:-.024em;color:var(--ink)}

.bcs-outcome{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:44px;align-items:start}
.bcs-outcome__text{grid-column:1 / span 7}
.bcs-outcome:not(.has-quote) .bcs-outcome__text{grid-column:4 / span 7}
.bcs-outcome__lbl{margin-bottom:18px}
.bcs-quote{grid-column:9 / 13;margin:0;padding:28px 0 0;border-top:2px solid var(--ink)}
.bcs-quote__q p{font-family:var(--f-h);font-size:clamp(1.25rem,2vw,1.65rem);font-weight:500;line-height:1.3;letter-spacing:-.018em;color:var(--ink)}
.bcs-quote__q p::before{content:"\201C";color:var(--blue)}
.bcs-quote__q p::after{content:"\201D";color:var(--blue)}
.bcs-quote__by{display:flex;flex-direction:column;gap:2px;margin-top:18px}
.bcs-quote__n{font-size:var(--t-sm);font-weight:600;color:var(--ink)}
.bcs-quote__r{font-size:var(--t-xs);color:var(--muted)}

/* ---------- where this lives --------------------------------------------- */
.bcs-where{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:var(--bdh-gap);align-items:stretch}
.bcs-where__card,.bcs-go{grid-column:span 4;min-width:0}
.bcs-where--0 .bcs-go{grid-column:1 / -1}
.bcs-where--1 .bcs-where__card{grid-column:span 7}
.bcs-where--1 .bcs-go{grid-column:span 5}
.bcs-where--3 .bcs-go{grid-column:1 / -1}
.bcs-where__card{position:relative;display:flex;border:1px solid var(--line);border-radius:var(--r-lg);background:var(--paper);overflow:hidden;transition:border-color var(--d2) var(--e),box-shadow var(--d3) var(--e),transform var(--d3) var(--e)}
.bcs-where__card:hover{border-color:var(--line-3);box-shadow:var(--sh-2);transform:translateY(-3px)}
.bcs-where__card:has(.bcs-where__a:focus-visible){outline:2px solid var(--blue);outline-offset:3px}
.bcs-where__a{display:flex;flex-direction:column;width:100%;color:inherit}
.bcs-where__a:focus-visible{outline:none}
.bcs-where__fig{aspect-ratio:16 / 10;overflow:hidden;background:var(--paper-3)}
.bcs-where--1 .bcs-where__a{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr)}
.bcs-where--1 .bcs-where__fig{aspect-ratio:auto;min-height:100%}
.bcs-where__fig picture{display:contents}
.bcs-where__img{display:block;width:100%;height:100%;object-fit:cover;transition:transform 1.1s var(--e)}
.bcs-where__card:hover .bcs-where__img{transform:scale(1.04)}
.bcs-where__body{display:flex;flex-direction:column;align-items:flex-start;gap:12px;flex:1;padding:clamp(20px,2vw,28px)}
.bcs-where__k{font-family:var(--f);font-size:var(--t-lbl);font-weight:500;letter-spacing:.14em;text-transform:uppercase;color:var(--blue-d)}
.bcs-where__t{font-family:var(--f-h);font-size:clamp(1.15rem,1.5vw,1.4rem);font-weight:500;line-height:1.22;letter-spacing:-.016em;color:var(--ink)}
.bcs-where__x{font-size:var(--t-sm);line-height:1.6;color:var(--txt)}
.bcs-where__m{display:flex;flex-wrap:wrap;gap:0 .9em;font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.1em;text-transform:uppercase;color:var(--muted);line-height:1.6}
.bcs-where__m span{min-width:0;max-width:100%}
.bcs-where__go{margin-top:auto;padding-top:6px}

.bcs-go{display:flex;flex-direction:column;align-items:flex-start;gap:16px;padding:clamp(24px,2.6vw,36px);border-radius:var(--r-lg);background:var(--ink);color:var(--on-ink-2)}
.bcs-go .lbl{color:var(--on-ink-3)}
.bcs-go__t{font-family:var(--f-h);font-size:clamp(1.4rem,2.2vw,1.95rem);font-weight:500;line-height:1.1;letter-spacing:-.024em;color:var(--on-ink)}
.bcs-go__x{max-width:46ch;font-size:var(--t-sm);line-height:1.6;color:var(--on-ink-2)}
.bcs-go__svc{display:flex;flex-direction:column;width:100%;border-top:1px solid var(--on-ink-line)}
.bcs-go__svc li{display:grid;grid-template-columns:18px minmax(0,1fr);align-items:baseline;gap:2px 10px;padding:10px 0;border-bottom:1px solid var(--on-ink-line)}
.bcs-go__tick{position:relative;top:-2px;width:11px;height:6px;border-left:2px solid var(--blue);border-bottom:2px solid var(--blue);transform:rotate(-45deg)}
.bcs-go__n{font-size:var(--t-sm);font-weight:500;line-height:1.4;color:var(--on-ink)}
.bcs-go__p{grid-column:2;font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.06em;color:var(--on-ink-3)}
.bcs-go__btn{margin-top:auto}
.bcs-where--0 .bcs-go,.bcs-where--3 .bcs-go{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));column-gap:var(--bdh-gap);row-gap:16px;align-items:start}
.bcs-where--0 .bcs-go > *,.bcs-where--3 .bcs-go > *{grid-column:1 / span 6}
.bcs-where--0 .bcs-go__svc,.bcs-where--3 .bcs-go__svc{grid-column:8 / 13;grid-row:1 / span 4}
.bcs-where--0 .bcs-go__btn,.bcs-where--3 .bcs-go__btn{justify-self:start}

/* ---------- the end: next case study + related --------------------------- */
.bcs-next{position:relative;margin-bottom:clamp(36px,4vw,56px);border:1px solid var(--line);border-radius:var(--r-xl);background:var(--paper);overflow:hidden;transition:border-color var(--d2) var(--e),box-shadow var(--d3) var(--e)}
.bcs-next:hover{border-color:var(--line-3);box-shadow:var(--sh-2)}
.bcs-next:has(.bcs-next__a:focus-visible){outline:2px solid var(--blue);outline-offset:3px}
.bcs-next__a{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));align-items:stretch;color:inherit}
.bcs-next__a:focus-visible{outline:none}
.bcs-next__fig{grid-column:1 / span 7;min-height:clamp(260px,30vw,440px);overflow:hidden;background:var(--paper-3)}
.bcs-next__fig picture{display:contents}
.bcs-next__img{display:block;width:100%;height:100%;object-fit:cover;transition:transform 1.2s var(--e)}
.bcs-next:hover .bcs-next__img{transform:scale(1.035)}
.bcs-next__body{grid-column:8 / 13;display:flex;flex-direction:column;align-items:flex-start;justify-content:center;gap:16px;padding:clamp(24px,3vw,44px)}
.bcs-next__k{display:flex;flex-wrap:wrap;align-items:center;gap:8px 14px;font-family:var(--f);font-size:var(--t-lbl);letter-spacing:.14em;text-transform:uppercase;color:var(--muted)}
.bcs-next__tag{display:inline-flex;align-items:center;height:24px;padding:0 9px;border-radius:var(--r-xs);background:var(--ink);color:var(--on-ink)}
.bcs-next__t{font-family:var(--f-h);font-size:clamp(1.45rem,2.5vw,2.25rem);font-weight:500;line-height:1.08;letter-spacing:-.028em;color:var(--ink)}
.bcs-next__c{font-size:var(--t-sm);line-height:1.55;color:var(--txt)}
.bcs-next__go{margin-top:8px}

/* ---------- smaller screens ---------------------------------------------- */
@media (max-width:1100px){
  .bcs-cover__dek{grid-column:1 / span 7}
  .bcs-spec{grid-column:8 / 13}
  .bcs-spread__text{grid-column:1 / span 7}
  .bcs-spread__fig{grid-column:8 / 13}
  .bcs-spread--flip .bcs-spread__fig{grid-column:1 / span 6}
  .bcs-spread--flip .bcs-spread__text{grid-column:7 / 13}
  .bcs-tl__list--4{grid-template-columns:repeat(2,minmax(0,1fr))}
  .bcs-tl__list--5{grid-template-columns:repeat(3,minmax(0,1fr))}
  .bcs-sheet__del{grid-column:1 / span 7}
  .bcs-sheet__side{grid-column:8 / 13}
  .bcs-where,.bcs-where--2{grid-template-columns:repeat(2,minmax(0,1fr))}
  .bcs-where__card,.bcs-go,.bcs-where--1 .bcs-where__card,.bcs-where--1 .bcs-go{grid-column:span 1}
  .bcs-where--1 .bcs-where__a{display:flex}
  .bcs-where--1 .bcs-where__fig{aspect-ratio:16 / 10;min-height:0}
  .bcs-where--0 .bcs-go,.bcs-where--3 .bcs-go,.bcs-where--2 .bcs-go{grid-column:1 / -1}
}
@media (max-width:1023px){
  .bcs-spread__fig{position:static}
  .bcs-sys__copy{grid-column:1 / span 5}
  .bcs-sys__fig{grid-column:6 / 13}
}
@media (max-width:860px){
  .bcs-cover__low{grid-template-columns:minmax(0,1fr)}
  .bcs-cover__dek,.bcs-spec{grid-column:1 / -1}
  .bcs-hero__box{aspect-ratio:4 / 3;border-radius:var(--r-lg)}
  .bcs-facts{grid-template-columns:minmax(0,1fr)}
  .bcs-facts__t,.bcs-facts__list{grid-column:1 / -1}
  .bcs-facts__t{padding-top:0}
  .bcs-facts__list,.bcs-facts__list--3{grid-template-columns:repeat(2,minmax(0,1fr));row-gap:24px}
  .bcs-facts__list--1{grid-template-columns:minmax(0,1fr)}
  /* the chapters panel: two by two, then one under the other */
  .bcs-toc__list,.bcs-toc__list--3,.bcs-toc__list--4{grid-template-columns:repeat(2,minmax(0,1fr))}
  .bcs-toc__it{border-right:0;border-bottom:1px solid var(--line-3)}
  .bcs-toc__it:nth-child(odd){border-right:1px solid var(--line-3)}
  .bcs-toc__it:nth-last-child(-n+2):nth-child(odd),.bcs-toc__it:nth-last-child(-n+2):nth-child(odd) ~ .bcs-toc__it{border-bottom:0}
  .bcs-toc__it:nth-child(odd) .bcs-toc__a{padding-left:0}
  .bcs-toc__it:nth-child(even) .bcs-toc__a{padding-right:0}
  .bcs-ch__head{grid-template-columns:minmax(0,1fr);row-gap:6px}
  .bcs-ch__no{font-size:clamp(4rem,22vw,6rem)}
  .bcs-brief,.bcs-spread,.bcs-tl__head,.bcs-sheet,.bcs-meas,.bcs-outcome{grid-template-columns:minmax(0,1fr)}
  .bcs-brief__k,.bcs-brief__q,.bcs-spread__text,.bcs-spread__fig,.bcs-spread--flip .bcs-spread__fig,.bcs-spread--flip .bcs-spread__text,
  .bcs-spread--solo .bcs-spread__text,.bcs-spread--flip.bcs-spread--solo .bcs-spread__text,
  .bcs-tl__h,.bcs-tl__lead,.bcs-sheet__del,.bcs-sheet__side,.bcs-meas__head,.bcs-meas__list,
  .bcs-outcome__text,.bcs-outcome:not(.has-quote) .bcs-outcome__text,.bcs-quote{grid-column:1 / -1}
  .bcs-brief__k{padding-top:0}
  .bcs-spread--flip .bcs-spread__fig{order:2}
  .bcs-fig--tall .bcs-fig__box{aspect-ratio:4 / 3}
  .bcs-fig--cine .bcs-fig__box{aspect-ratio:3 / 2;border-radius:var(--r-lg)}
  .bcs-sheet--nodel .bcs-sheet__side{grid-template-columns:minmax(0,1fr)}
  .bcs-sys{grid-template-columns:minmax(0,1fr)}
  .bcs-sys__copy,.bcs-sys__fig{grid-column:1 / -1}
  .bcs-sys__key{flex-direction:row;flex-wrap:wrap;gap:8px 18px}
  /* the timeline turns vertical: the line runs down the left */
  .bcs-tl__list,.bcs-tl__list--2,.bcs-tl__list--3,.bcs-tl__list--5,.bcs-tl__list--6{grid-template-columns:minmax(0,1fr);row-gap:0}
  .bcs-tl__it{padding:0 0 28px 34px}
  .bcs-tl__it::before{left:7px;right:auto;top:15px;bottom:0;width:1px;height:auto;transform-origin:50% 0}
  .bcs-tl__it:last-child::before{display:none}
  .bcs-tl.is-anim .bcs-tl__it::before{transform:scaleY(0)}
  /* phones and tablets: the lead full width, then two to a row (one column under 600px) */
  .bcs-gal{grid-template-columns:repeat(2,minmax(0,1fr))}
  .bcs-gal__it:first-child,.bcs-gal__it:nth-child(even):last-child{grid-column:1 / -1}
  .bcs-gal__a{flex:none;aspect-ratio:1 / 1}
  .bcs-gal__it:first-child .bcs-gal__a,.bcs-gal__it:nth-child(even):last-child .bcs-gal__a{aspect-ratio:3 / 2}
  .bcs-where,.bcs-where--1,.bcs-where--2{grid-template-columns:minmax(0,1fr)}
  .bcs-where__card,.bcs-go{grid-column:1 / -1}
  .bcs-where--0 .bcs-go,.bcs-where--3 .bcs-go{display:flex}
  .bcs-next__a{display:flex;flex-direction:column}
  .bcs-next__fig{min-height:0;aspect-ratio:3 / 2}
  .bcs-figs__list,.bcs-figs__list--2,.bcs-figs__list--4{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:480px){
  .bcs-toc__list,.bcs-toc__list--2,.bcs-toc__list--3,.bcs-toc__list--4{grid-template-columns:minmax(0,1fr)}
  .bcs-toc__it,.bcs-toc__it:nth-child(odd),
  .bcs-toc__it:nth-last-child(-n+2):nth-child(odd),.bcs-toc__it:nth-last-child(-n+2):nth-child(odd) ~ .bcs-toc__it{border-right:0;border-bottom:1px solid var(--line-3)}
  .bcs-toc__list,.bcs-toc__list--2,.bcs-toc__list--3,.bcs-toc__list--4{border-bottom:0}        /* each chapter's rule closes it */
  .bcs-toc__it .bcs-toc__a,.bcs-toc__it:nth-child(even) .bcs-toc__a{display:grid;grid-template-columns:52px minmax(0,1fr);column-gap:8px;row-gap:4px;padding:16px 0}
  .bcs-toc__n{grid-row:span 2;font-size:2rem}
}
@media (max-width:680px){
  .bcs-spec a{display:inline-flex;align-items:center;min-height:44px}
  .bcs-spec__list{row-gap:0}
  .bcs-spec__i{padding-block:10px}
}
@media (max-width:600px){
  .bcs-sys{padding:18px 14px;border-radius:var(--r-lg)}
  .bcs-sys__ui .bdh-ui__bar{height:auto;min-height:44px;padding-block:10px;white-space:normal}
  .bcs-sys__title{overflow:visible;line-height:1.4}
  .bcs-sys__row{padding:12px 14px;column-gap:10px}
  .bcs-sys__w{grid-column:2 / -1;grid-row:2}
  .bcs-sys__d{grid-row:3}
  .bcs-sys__msg{max-width:94%}
  .bcs-cover__min{padding-left:0;border-left:0}
  .bcs-spec{grid-template-columns:minmax(0,1fr)}
  .bcs-gal{grid-template-columns:minmax(0,1fr)}
  .bcs-gal__a,.bcs-gal__it:first-child .bcs-gal__a,.bcs-gal__it:nth-child(even):last-child .bcs-gal__a{aspect-ratio:4 / 3}
  .bcs-figs__list,.bcs-figs__list--2,.bcs-figs__list--4{grid-template-columns:minmax(0,1fr)}
  .bcs-go__btn{width:100%}
  .bcs-del__it{grid-template-columns:40px minmax(0,1fr)}
}
@media (prefers-reduced-motion:reduce){
  .bcs-gal__img,.bcs-where__img,.bcs-next__img,.bcs-where__card{transition:none}
  .bcs-gal__a:hover .bcs-gal__img,.bcs-where__card:hover .bcs-where__img,.bcs-next:hover .bcs-next__img{transform:none}
  .bcs-where__card:hover{transform:none}
}
@media print{
  .bcs-strip,.bcs-gut,.bcs-gal__zoom,.bcs-go__btn{display:none}
  .bcs-cover{padding-bottom:24px}
  .bcs-hero{margin-top:16px}
}

/* touch screens (phones and tablets): 44px tap targets (integrator, responsive pass) */
@media (pointer:coarse){
  .bcs-spec__list a,.bcs-spec__i dd a{display:inline-flex;align-items:center;min-height:44px}
}