/* ==========================================================================
   dr Marek Borowiński — Brand Identity Case Study
   Źródło prawdy: pliki autora („mb logo.ai”, prezentacja i mockupy projektu)
   ========================================================================== */

/* ---------- Tokeny ---------- */
.bk {
  /* Paleta oficjalna — wartości pobrane z pliku logo (wypełnienia wektorów) */
  --navy: #0A1E57;      /* sygnet „mB”, imię i nazwisko */
  --blue: #0E4278;      /* „dr”, podpis specjalizacji */
  --white: #FFFFFF;
  /* Pomocnicze — robocze wartości prezentacji */
  --paper: #F3F4F6;
  --gray: #A8ABB3;

  --navy-deep: color-mix(in srgb, var(--navy) 82%, #000);
  --ink: var(--navy);
  --muted-light: #4C5679;                 /* 7.0:1 na bieli */
  --muted-dark: rgba(255, 255, 255, .72); /* ~9:1 na granacie */
  --line-light: rgba(10, 30, 87, .14);
  --line-dark: rgba(255, 255, 255, .16);

  /* Kolory logo w SVG inline — przełączane per kontekst */
  --lg-sign: var(--navy);
  --lg-sign2: var(--blue);
  --lg-name: var(--navy);
  --lg-tag: var(--blue);

  /* Typografia prezentacji (kroje pomocnicze — logotyp to oryginalne kontury Massilia) */
  --f-sans: "Manrope", sans-serif;
  --f-head: "Nohemi", sans-serif;
  --f-mono: "Manrope", sans-serif;

  --fs-hero: clamp(2.5rem, 1rem + 4.6vw, 6.2rem);
  --fs-h2: clamp(2rem, 1.1rem + 2.6vw, 4rem);
  --fs-h3: clamp(1.4rem, 1.1rem + 1vw, 2.1rem);
  --fs-lead: clamp(1.1rem, .98rem + .5vw, 1.45rem);
  --fs-body: clamp(.98rem, .95rem + .15vw, 1.075rem);
  --fs-small: .875rem;
  --fs-micro: .75rem;

  /* Przestrzeń */
  --gutter: clamp(16px, 4.2vw, 72px);
  --maxw: 1600px;
  --pad-x: max(var(--gutter), calc((100vw - var(--maxw)) / 2));
  --sp-s: 1rem;
  --sp-m: clamp(1.5rem, 1rem + 1.5vw, 2.5rem);
  --sp-l: clamp(3rem, 2rem + 4vw, 6.5rem);
  --sp-xl: clamp(5rem, 3rem + 8vw, 11rem);
  /* Wysokość nagłówka strony nadrzędnej (np. portfolio) nad paskiem rozdziałów — przy osadzeniu ustaw np. 80px. */
  --site-offset: 72px;
  --header-h: 56px;
  --nav-h: calc(var(--site-offset) + var(--header-h));

  --ease-out: cubic-bezier(.22, 1, .36, 1);
  --ease-io: cubic-bezier(.65, 0, .35, 1);
}

/* ---------- Reset ---------- */
:where(.bk) *, :where(.bk) *::before, :where(.bk) *::after { box-sizing: border-box; }
html.bk-page { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-behavior: smooth; }
html.bk-page.bk-motion { scroll-behavior: auto; }
.bk {
  margin: 0; background: var(--navy); color: var(--white);
  font-family: var(--f-sans); font-size: var(--fs-body); font-weight: 400; line-height: 1.65;
  -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; overflow-x: clip;
}
:where(.bk) img, :where(.bk) svg { display: block; max-width: 100%; }
:where(.bk) img { height: auto; }
:where(.bk) h1, :where(.bk) h2, :where(.bk) h3, :where(.bk) p, :where(.bk) ol, :where(.bk) ul, :where(.bk) dl, :where(.bk) dd, :where(.bk) figure { margin: 0; }
:where(.bk) ol, :where(.bk) ul { padding: 0; list-style: none; }
:where(.bk) button, :where(.bk) input, :where(.bk) textarea { font: inherit; color: inherit; }
:where(.bk) button { cursor: pointer; background: none; border: 0; padding: 0; }
:where(.bk) a { color: inherit; }
:where(.bk) ::selection { background: var(--blue); color: var(--white); }
:where(.bk) :focus-visible { outline: 2px solid currentColor; outline-offset: 4px; border-radius: 2px; }

.bk-visually-hidden {
  position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
.bk-skip-link {
  position: fixed; left: 16px; top: -60px; z-index: 200; background: var(--white); color: var(--navy);
  padding: .7rem 1rem; font-weight: 600; text-decoration: none; transition: top .3s;
}
.bk-skip-link:focus { top: calc(var(--site-offset) + 12px); }

/* Kontenery inline logo */
:where(.bk) [data-mark] svg, :where(.bk) [data-pieces] { width: 100%; height: auto; overflow: visible; }
:where(.bk) [data-mark] { display: block; line-height: 0; }

/* ---------- Typografia ---------- */
.bk-wrap { padding-inline: var(--pad-x); }
.bk-h2 { font-size: var(--fs-h2); font-weight: 700; line-height: .98; letter-spacing: -0.012em; max-width: 14ch; text-wrap: balance; }
.bk-lead { font-size: var(--fs-lead); line-height: 1.5; font-weight: 500; letter-spacing: -0.003em; }
.bk-label { font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; opacity: .78; }
.bk-note { font-size: var(--fs-small); line-height: 1.55; color: var(--muted-light); max-width: 60ch; }
.bk-note b { font-weight: 600; color: var(--ink); }
.bk-note--dark, .bk-ch--navy .bk-note { color: var(--muted-dark); }
.bk-note--dark b, .bk-ch--navy .bk-note b { color: var(--white); }

.bk-eyebrow { display: flex; align-items: center; gap: 14px; margin-bottom: var(--sp-m); font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; }
.bk-eyebrow__num { font-weight: 500; }
.bk-eyebrow__num::after { content: ""; display: inline-block; width: 40px; height: 1px; background: currentColor; opacity: .5; vertical-align: middle; margin-left: 14px; }
.bk-eyebrow__label { opacity: .8; }

/* ---------- Rozdziały ---------- */
.bk-ch { position: relative; }
.bk-ch--navy { background: var(--navy); color: var(--white); --lg-sign: #fff; --lg-sign2: #fff; --lg-name: #fff; --lg-tag: #fff; }
.bk-ch--white { background: var(--white); color: var(--ink); }
.bk-ch--paper { background: var(--paper); color: var(--ink); }
.bk-ch--white :focus-visible, .bk-ch--paper :focus-visible { outline-color: var(--navy); }

/* ==========================================================================
   NAWIGACJA
   ========================================================================== */
.bk-progress { position: fixed; inset: auto 0 0 0; height: 2px; z-index: 120; background: rgba(168,171,179,.22); pointer-events: none; }
.bk-progress__bar { display: block; height: 100%; background: var(--blue); transform-origin: 0 50%; transform: scaleX(0); }
.bk-site-header[data-nav-theme="dark"] ~ .bk-progress .bk-progress__bar { background: #fff; }

.bk-site-header {
  position: fixed; inset: var(--site-offset) 0 auto 0; z-index: 110; height: var(--header-h);
  display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: clamp(14px, 3vw, 40px);
  padding-inline: var(--gutter); color: var(--white); transition: color .5s var(--ease-out);
  --lg-sign: currentColor; --lg-sign2: currentColor;
}
.bk-site-header::before {
  content: ""; position: absolute; inset: 0; z-index: -1; opacity: 0;
  background: rgba(10,30,87,.82); -webkit-backdrop-filter: blur(12px); backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line-dark); transition: opacity .5s var(--ease-out), background-color .5s var(--ease-out), border-color .5s;
}
.bk-site-header.bk-is-scrolled::before { opacity: 1; }
.bk-site-header[data-nav-theme="light"] { color: var(--navy); }
.bk-site-header[data-nav-theme="light"]::before { background: rgba(255,255,255,.86); border-bottom-color: var(--line-light); }
.bk-site-header__brand { display: inline-flex; align-items: center; gap: 10px; min-height: 44px; font-weight: 700; font-size: .95rem; letter-spacing: -0.003em; text-decoration: none; white-space: nowrap; }
.bk-site-header__sign { width: 15px; flex: none; }
.bk-site-header__chapter { min-width: 0; overflow: hidden; display: flex; align-items: center; gap: 12px; font-family: var(--f-mono); font-size: 11px; letter-spacing: .01em; white-space: nowrap; }
.bk-site-header__num { font-variant-numeric: tabular-nums; font-weight: 500; }
.bk-site-header__sep { width: 24px; height: 1px; background: currentColor; opacity: .45; flex: none; }
.bk-site-header__title { opacity: .78; overflow: hidden; text-overflow: ellipsis; }
.bk-menu-btn { justify-self: end; display: inline-flex; align-items: center; gap: 12px; height: 44px; padding: 0 0 0 10px; font-family: var(--f-mono); font-size: 11px; letter-spacing: .01em; }
.bk-menu-btn__icon { position: relative; width: 30px; height: 30px; border: 1px solid currentColor; border-radius: 50%; transition: transform .5s var(--ease-out); }
.bk-menu-btn__icon i { position: absolute; left: 9px; right: 9px; height: 1px; background: currentColor; }
.bk-menu-btn__icon i:first-child { top: 12px; }
.bk-menu-btn__icon i:last-child { top: 16px; }
.bk-menu-btn:hover .bk-menu-btn__icon { transform: rotate(90deg); }
@media (max-width: 599px) {
  .bk-menu-btn__label, .bk-site-header__title { display: none; }
  .bk-site-header__brand > span:last-child { font-size: .88rem; }
}
@media (max-width: 359px) { .bk-site-header__chapter { display: none; } }

.bk-rail { position: fixed; right: clamp(12px, 1.4vw, 26px); top: 50%; z-index: 100; transform: translateY(-50%); display: none; color: var(--white); transition: color .5s var(--ease-out); }
.bk-rail[data-nav-theme="light"] { color: var(--navy); }
.bk-rail__list { display: flex; flex-direction: column; gap: 2px; }
.bk-rail__link { position: relative; display: flex; align-items: center; justify-content: flex-end; width: 32px; height: 20px; text-decoration: none; }
.bk-rail__tick { width: 10px; height: 1px; background: currentColor; opacity: .38; transition: width .45s var(--ease-out), opacity .45s var(--ease-out); }
.bk-rail__label { position: absolute; right: 30px; top: 50%; transform: translate(8px, -50%); white-space: nowrap; font-family: var(--f-mono); font-size: 11px; letter-spacing: .01em; opacity: 0; pointer-events: none; transition: opacity .35s var(--ease-out), transform .35s var(--ease-out); }
.bk-rail__label b { font-weight: 500; margin-right: 8px; font-variant-numeric: tabular-nums; }
.bk-rail__link:hover .bk-rail__tick, .bk-rail__link:focus-visible .bk-rail__tick { width: 22px; opacity: 1; }
.bk-rail__link:hover .bk-rail__label, .bk-rail__link:focus-visible .bk-rail__label { opacity: 1; transform: translate(0, -50%); }
.bk-rail__link[aria-current="true"] .bk-rail__tick { width: 26px; opacity: 1; height: 2px; }
@media (min-width: 1024px) { .bk-rail { display: block; } }

.bk-menu { position: fixed; inset: 0; z-index: 150; background: var(--navy-deep); color: var(--white); overflow-y: auto; display: flex; align-items: flex-start; }
.bk-menu[hidden] { display: none; }
.bk-menu__inner { width: 100%; max-width: 1400px; margin: 0 auto; padding: calc(var(--site-offset) + 1.1rem) var(--gutter) 2rem; }
.bk-menu__head { display: flex; justify-content: space-between; align-items: center; gap: 1rem; margin-bottom: var(--sp-m); }
.bk-menu__eyebrow { font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; opacity: .7; }
.bk-menu__list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); column-gap: var(--sp-l); border-top: 1px solid var(--line-dark); }
.bk-menu__list li { border-bottom: 1px solid var(--line-dark); }
.bk-menu__list a { display: flex; align-items: baseline; gap: 1.2rem; padding: .9rem 0; text-decoration: none; font-size: clamp(1.3rem, 1rem + 1.2vw, 2.2rem); font-weight: 700; letter-spacing: -0.009em; line-height: 1.1; transition: opacity .3s, padding .4s var(--ease-out); }
.bk-menu__list a span { font-family: var(--f-mono); font-size: var(--fs-micro); font-weight: 400; letter-spacing: .06em; opacity: .6; min-width: 2em; }
.bk-menu__list a:hover, .bk-menu__list a:focus-visible, .bk-menu__list a[aria-current="true"] { padding-left: .6rem; }
.bk-menu__list a[aria-current="true"]::after { content: ""; width: 6px; height: 6px; border-radius: 50%; background: currentColor; align-self: center; margin-left: auto; }
.bk-menu__foot { display: flex; justify-content: space-between; align-items: center; gap: 1rem; margin-top: var(--sp-m); }
.bk-menu__top, .bk-menu__close { min-height: 44px; display: inline-flex; align-items: center; gap: .5rem; text-decoration: none; font-family: var(--f-mono); letter-spacing: .01em; font-size: var(--fs-micro); }
.bk-menu__close span { font-size: 1.1rem; }
@media (max-width: 767px) { .bk-menu__list { grid-template-columns: 1fr; } }

.bk-toast {
  position: fixed; left: 50%; bottom: 28px; z-index: 260; transform: translate(-50%, calc(100% + 48px));
  background: var(--white); color: var(--navy); padding: .8rem 1.2rem; font-size: var(--fs-small); font-weight: 600;
  box-shadow: 0 14px 40px rgba(10,30,87,.28); transition: transform .5s var(--ease-out), visibility .5s; pointer-events: none; visibility: hidden;
}
.bk-toast.bk-is-visible { transform: translate(-50%, 0); visibility: visible; }
.bk-toast i { display: inline-block; width: .9em; height: .9em; margin-right: .55em; vertical-align: -.1em; box-shadow: inset 0 0 0 1px rgba(10,30,87,.25); }

/* Wspólne kontrolki */
.bk-chip { min-height: 40px; padding: .45rem .95rem; border: 1px solid currentColor; border-radius: 99px; font-size: var(--fs-small); font-weight: 600; letter-spacing: -0.002em; opacity: .72; transition: opacity .3s, background-color .3s, color .3s; }
.bk-chip:hover { opacity: 1; }
.bk-chip.bk-is-active, .bk-chip[aria-pressed="true"] { opacity: 1; background: currentColor; }
.bk-ch--navy .bk-chip.bk-is-active, .bk-ch--navy .bk-chip[aria-pressed="true"] { background: #fff; border-color: #fff; }
.bk-ch--navy .bk-chip.bk-is-active, .bk-ch--navy .bk-chip[aria-pressed="true"] { color: var(--navy); }
.bk-ch--navy .bk-chip.bk-is-active *, .bk-ch--navy .bk-chip[aria-pressed="true"] * { color: var(--navy); }
.bk-ch--white .bk-chip[aria-pressed="true"], .bk-ch--paper .bk-chip[aria-pressed="true"] { background: var(--navy); border-color: var(--navy); color: #fff; }

/* ==========================================================================
   01 — WPROWADZENIE
   ========================================================================== */
.bk-hero { min-height: calc(100vh - var(--site-offset)); min-height: calc(100svh - var(--site-offset)); display: grid; grid-template-rows: minmax(0, 1fr) auto; overflow: hidden; padding-top: var(--header-h); }
.bk-hero__pattern, .bk-final__pattern { position: absolute; inset: 0; pointer-events: none; overflow: hidden; }
.bk-hero__pattern svg, .bk-final__pattern svg { position: absolute; height: 175%; width: auto; max-width: none; right: -14%; top: -38%; fill: rgba(255,255,255,.035); }
.bk-hero__stage { position: relative; display: grid; place-items: center; padding: clamp(1.5rem, 5vh, 4rem) var(--gutter); }
.bk-hero__logo { width: min(84vw, 980px); position: relative; z-index: 1; }
.bk-hero__content { position: relative; z-index: 2; display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); align-items: end; column-gap: var(--sp-l); padding: 0 var(--pad-x) clamp(1.6rem, 4.5vh, 3.4rem); }
.bk-hero__content .bk-eyebrow { grid-column: 1 / -1; margin-bottom: 1rem; }
.bk-hero__title { font-size: var(--fs-hero); font-weight: 800; line-height: .9; letter-spacing: -0.017em; }
.bk-hero__title .bk-w:nth-child(2) > span { font-weight: 300; }
.bk-hero__aside { display: grid; gap: 1.6rem; justify-items: start; padding-bottom: .6rem; }
.bk-hero__lead { color: var(--muted-dark); max-width: 38ch; }
.bk-scroll-cue { display: inline-flex; align-items: center; gap: 14px; min-height: 44px; text-decoration: none; font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; }
.bk-scroll-cue__line { position: relative; width: 1px; height: 44px; background: rgba(255,255,255,.25); overflow: hidden; }
.bk-scroll-cue__line::after { content: ""; position: absolute; left: 0; top: -40%; width: 1px; height: 40%; background: #fff; animation: bk-cue 2.2s var(--ease-io) infinite; }
@keyframes bk-cue { to { top: 100%; } }
@media (max-width: 767px) {
  .bk-hero__content { grid-template-columns: 1fr; row-gap: 1.4rem; }
  .bk-hero__logo { width: 92vw; }
}

/* ==========================================================================
   02 — CZŁOWIEK
   ========================================================================== */
.bk-person { padding-block: calc(var(--sp-xl) + var(--nav-h)) var(--sp-xl); overflow: hidden; }
.bk-person__bg { position: absolute; inset: 0; pointer-events: none; overflow: hidden; }
.bk-person__bg { -webkit-mask-image: linear-gradient(#000 40%, transparent 85%); mask-image: linear-gradient(#000 40%, transparent 85%); }
.bk-person__bg svg { position: absolute; height: 120%; width: auto; max-width: none; left: -9%; top: -4%; fill: none; stroke: rgba(10,30,87,.09); stroke-width: .12; }
.bk-person__head, .bk-person__body, .bk-person__values { position: relative; }
.bk-person__type { position: relative; margin-block: var(--sp-l); display: grid; gap: 0; line-height: .82; font-weight: 800; letter-spacing: -0.019em; white-space: nowrap; }
.bk-person__line { display: block; font-size: clamp(3rem, 14.2vw, 17rem); }
.bk-person__line--a { padding-left: var(--pad-x); }
.bk-person__line--b { color: transparent; -webkit-text-stroke: 1.5px var(--navy); text-align: right; padding-right: var(--pad-x); }
.bk-person__body { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: var(--sp-l); align-items: start; }
.bk-person__text { display: grid; gap: 1.2rem; max-width: 52ch; }
.bk-person__text p:not(.bk-lead) { color: var(--muted-light); }
.bk-focus { display: grid; border-top: 1px solid var(--line-light); }
.bk-focus__item { display: flex; gap: 1.2rem; align-items: baseline; padding: 1.1rem 0; border-bottom: 1px solid var(--line-light); font-size: clamp(1.3rem, 1rem + 1.2vw, 2.2rem); font-weight: 700; letter-spacing: -0.011em; line-height: 1.15; }
.bk-focus__item.bk-is-off { color: var(--muted-light); font-weight: 400; text-decoration: line-through; text-decoration-thickness: 1px; }
.bk-focus__num { font-family: var(--f-mono); font-size: var(--fs-small); font-weight: 400; min-width: 1.5em; text-decoration: none; display: inline-block; }
.bk-person__values { margin-top: var(--sp-xl); display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 2fr); gap: var(--sp-l); align-items: start; }
.bk-values__head { display: grid; gap: .8rem; }
.bk-values__claim { font-size: var(--fs-h3); font-weight: 700; letter-spacing: -0.009em; line-height: 1.15; }
.bk-values { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 1px solid var(--navy); }
.bk-values li { padding: 1rem .8rem 1.4rem 0; border-bottom: 1px solid var(--line-light); font-weight: 600; font-size: clamp(1rem, .9rem + .4vw, 1.3rem); letter-spacing: -0.006em; }
.bk-values span { display: block; font-family: var(--f-mono); font-size: var(--fs-micro); font-weight: 400; color: var(--muted-light); margin-bottom: 1.6rem; }
@media (max-width: 1023px) {
  .bk-person__body, .bk-person__values { grid-template-columns: 1fr; }
}
@media (max-width: 599px) { .bk-values { grid-template-columns: repeat(2, minmax(0, 1fr)); } .bk-person__line--b { -webkit-text-stroke-width: 1px; } }

/* ==========================================================================
   03 — WYZWANIE
   ========================================================================== */
.bk-challenge { padding-top: var(--sp-xl); }
.bk-challenge__head { display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr); column-gap: var(--sp-l); align-items: end; padding-bottom: var(--sp-l); }
.bk-challenge__head .bk-eyebrow { grid-column: 1 / -1; }
.bk-challenge__intro { color: var(--muted-light); max-width: 46ch; }
@media (max-width: 1023px) { .bk-challenge__head { grid-template-columns: 1fr; row-gap: 1.4rem; } }

.bk-duo { position: relative; display: grid; }
.bk-duo__half { position: relative; overflow: hidden; }
.bk-duo__inner { padding: var(--sp-l) var(--pad-x); display: grid; gap: var(--sp-m); align-content: start; }
.bk-duo__half--retail { background: var(--paper); color: var(--navy); }
.bk-duo__half--color { background: var(--navy); color: #fff; }
.bk-duo__label { font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; display: flex; gap: 14px; }
.bk-duo__label span { opacity: .6; }
.bk-duo__word { font-size: clamp(3.4rem, 1.6rem + 6.6vw, 9.4rem); font-weight: 800; letter-spacing: -0.018em; line-height: .84; }
.bk-duo__half--color .bk-duo__word { font-weight: 200; letter-spacing: -0.009em; }
.bk-duo__list { display: grid; border-top: 1px solid var(--line-light); max-width: 30rem; }
.bk-duo__list li { padding: .8rem 0; border-bottom: 1px solid var(--line-light); font-weight: 600; }
.bk-percept { display: grid; gap: 1rem; max-width: 30rem; }
.bk-percept__pair { display: grid; grid-template-columns: 1fr 1fr; aspect-ratio: 2 / 1; }
.bk-percept__field { display: grid; place-items: center; }
.bk-percept__field--light { background: #fff; }
.bk-percept__field--dark { background: var(--navy-deep); box-shadow: inset 0 0 0 1px var(--line-dark); }
.bk-percept__field i { width: 34%; aspect-ratio: 1; background: var(--gray); }
.bk-percept figcaption { font-size: var(--fs-small); color: var(--muted-dark); line-height: 1.55; }
.bk-percept figcaption b { color: #fff; font-weight: 600; display: block; margin-bottom: .2rem; }
.bk-duo__merge { background: var(--navy); color: #fff; display: grid; justify-items: center; align-content: center; gap: clamp(1rem, 3vh, 2rem); padding: var(--sp-l) var(--gutter); text-align: center; --lg-sign: #fff; --lg-sign2: #fff; --lg-tag: #fff; }
.bk-duo__sign { width: clamp(70px, 9vw, 130px); }
.bk-duo__tag { width: min(80vw, 640px); }
.bk-duo__claim { font-size: clamp(1.7rem, 1rem + 2.6vw, 3.6rem); font-weight: 700; letter-spacing: -0.012em; line-height: 1.05; max-width: 16ch; }
/* Wersja przypięta (desktop, ruch): połówki zbiegają się do środka */
.bk-duo.bk-is-pinned { height: 100vh; height: 100svh; overflow: hidden; }
.bk-duo.bk-is-pinned .bk-duo__half { position: absolute; top: 0; bottom: 0; width: 50%; display: grid; align-content: center; }
.bk-duo.bk-is-pinned .bk-duo__half--retail { left: 0; }
.bk-duo.bk-is-pinned .bk-duo__half--color { right: 0; }
.bk-duo.bk-is-pinned .bk-duo__inner { padding-block: var(--nav-h) 2rem; }
.bk-duo.bk-is-pinned .bk-duo__half--retail .bk-duo__inner { padding-left: var(--pad-x); padding-right: clamp(2rem, 4vw, 5rem); }
.bk-duo.bk-is-pinned .bk-duo__half--color .bk-duo__inner { padding-right: var(--pad-x); padding-left: clamp(2rem, 4vw, 5rem); }
.bk-duo.bk-is-pinned .bk-duo__merge { position: absolute; inset: 0; opacity: 0; visibility: hidden; padding-top: var(--nav-h); }
@media (min-width: 768px) and (max-width: 1023px), (max-width: 1023px) {
  .bk-duo__half--color .bk-duo__inner { padding-bottom: var(--sp-l); }
}
.bk-challenge__areas { padding-block: var(--sp-l) var(--sp-xl); display: grid; gap: 1rem; }
.bk-areas { font-size: clamp(1.25rem, .9rem + 1.6vw, 2.6rem); font-weight: 600; letter-spacing: -0.011em; line-height: 1.2; max-width: 34ch; }
.bk-areas i { font-style: normal; font-weight: 200; opacity: .45; }

/* ==========================================================================
   04 — IDEA
   ========================================================================== */
.bk-idea__pin { min-height: 100vh; min-height: 100svh; display: grid; align-items: center; padding-block: calc(var(--nav-h) + 2rem) 3rem; overflow: hidden; }
.bk-idea__grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: var(--sp-l); align-items: center; }
.bk-idea__copy { display: grid; gap: var(--sp-m); align-content: center; }
.bk-idea__copy .bk-eyebrow { margin-bottom: 0; }
.bk-idea__text { display: grid; gap: 1rem; color: var(--muted-light); max-width: 46ch; }
.bk-idea__steps { display: grid; border-top: 1px solid var(--line-light); max-width: 26rem; }
.bk-idea__steps li { display: flex; gap: 1rem; padding: .7rem 0; border-bottom: 1px solid var(--line-light); font-weight: 600; opacity: .4; transition: opacity .5s var(--ease-out); }
.bk-idea__steps li.bk-is-on { opacity: 1; }
.bk-idea__steps span { font-family: var(--f-mono); font-size: var(--fs-micro); font-weight: 400; padding-top: .25em; }
.bk-reduced-motion .bk-idea__steps li, .bk-motion-failed .bk-idea__steps li { opacity: 1; }
.bk-idea__stage { display: grid; gap: 1rem; justify-items: center; }
.bk-idea__canvas { position: relative; height: min(66vh, 620px); aspect-ratio: 61.08 / 97.69; max-width: 80vw; }
.bk-idea__sign { position: absolute; inset: 0; width: 100%; height: 100%; fill: var(--navy); }
.bk-idea__sign .bk-p-d, .bk-idea__sign .bk-p-r { fill: var(--blue); }
.bk-idea__letter { font-family: var(--f-sans); font-weight: 300; fill: var(--navy); opacity: 0; }
.bk-idea__letter--d, .bk-idea__letter--r { fill: var(--blue); }
.bk-idea__stage .bk-note { text-align: center; max-width: 44ch; }
@media (max-width: 1023px) {
  .bk-idea__grid { grid-template-columns: 1fr; }
  .bk-idea__canvas { height: min(58vh, 520px); }
}

/* ==========================================================================
   05 — MONOGRAM
   ========================================================================== */
.bk-mono__pin { min-height: 100vh; min-height: 100svh; display: grid; align-items: center; padding-block: calc(var(--nav-h) + 2rem) 3rem; }
.bk-mono__grid { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: var(--sp-l); align-items: center; }
.bk-mono__copy { display: grid; gap: var(--sp-m); }
.bk-mono__copy .bk-eyebrow { margin-bottom: 0; }
.bk-mono__lead { color: var(--muted-dark); max-width: 46ch; }
.bk-explorer { display: grid; gap: .9rem; }
.bk-explorer__btns { display: flex; flex-wrap: wrap; gap: .5rem; }
.bk-explorer__desc { font-size: var(--fs-small); color: var(--muted-dark); min-height: 3.2em; max-width: 44ch; }
.bk-mono__figure { display: grid; gap: 1rem; justify-items: center; }
.bk-mono__frame { position: relative; display: grid; grid-template-columns: auto minmax(0, 1fr); gap: clamp(1rem, 2vw, 3rem); align-items: center; min-width: 0; }
.bk-mono__svg { height: min(62vh, 640px); width: auto; aspect-ratio: 81.08 / 113.69; fill: #fff; overflow: hidden; }
.bk-mono__svg .bk-p-d, .bk-mono__svg .bk-p-r { fill: #fff; }
.bk-mono__svg .bk-ov { fill: none; stroke: #fff; stroke-width: .22; vector-effect: non-scaling-stroke; }
.bk-mono__svg .bk-ov-line { stroke-width: 1px; opacity: .6; }
.bk-mono__svg .bk-ov-dash { stroke-dasharray: 4 4; }
.bk-mono__svg .bk-ov-dot { fill: var(--navy); stroke: #fff; stroke-width: 1px; }
.bk-mono__svg .bk-ov-num { fill: #fff; font-family: var(--f-mono); font-size: 2.6px; }
.bk-mono__svg .bk-ov-g { opacity: 0; transition: opacity .5s var(--ease-out); }
.bk-mono__svg .bk-ov-g.bk-is-on { opacity: 1; }
.bk-mono__svg.bk-is-zoomed .bk-ov-g { opacity: 0 !important; }
.bk-mono__svg .bk-outline { fill: none; stroke: #fff; stroke-width: 1px; vector-effect: non-scaling-stroke; }
.bk-mono__notes { display: grid; gap: 0; border-top: 1px solid var(--line-dark); min-width: 10.5rem; }
.bk-mono__notes li { display: flex; gap: .8rem; padding: .7rem 0; border-bottom: 1px solid var(--line-dark); font-size: var(--fs-small); font-weight: 600; line-height: 1.35; opacity: .45; transition: opacity .5s var(--ease-out); }
.bk-mono__notes li.bk-is-on { opacity: 1; }
.bk-mono__notes span { font-family: var(--f-mono); font-weight: 400; font-size: var(--fs-micro); }
.bk-reduced-motion .bk-mono__notes li, .bk-motion-failed .bk-mono__notes li, .bk-static-mono .bk-mono__notes li { opacity: 1; }
.bk-reduced-motion .bk-mono__svg .bk-ov-g, .bk-motion-failed .bk-mono__svg .bk-ov-g, .bk-static-mono .bk-mono__svg .bk-ov-g { opacity: 1; }
@media (max-width: 1023px) {
  .bk-mono__grid { grid-template-columns: 1fr; }
  .bk-mono__frame { grid-template-columns: 1fr; justify-items: center; }
  .bk-mono__svg { height: min(62vh, 520px); max-width: 86vw; }
  .bk-mono__notes { width: 100%; }
}

/* ==========================================================================
   06 — KONSTRUKCJA
   ========================================================================== */
.bk-build__pin { position: relative; min-height: 100vh; min-height: 100svh; display: grid; align-items: center; padding-block: calc(var(--nav-h) + 2rem) 3rem; overflow: hidden; }
.bk-build__grid-bg { position: absolute; inset: 0; pointer-events: none;
  background-image: linear-gradient(var(--line-light) 1px, transparent 1px), linear-gradient(90deg, var(--line-light) 1px, transparent 1px);
  background-size: 48px 48px; background-position: center; opacity: .5;
  -webkit-mask-image: radial-gradient(ellipse at 65% 50%, #000 30%, transparent 75%); mask-image: radial-gradient(ellipse at 65% 50%, #000 30%, transparent 75%); }
.bk-build__layout { position: relative; display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: var(--sp-l); align-items: center; }
.bk-build__copy { display: grid; gap: var(--sp-m); }
.bk-build__copy .bk-eyebrow { margin-bottom: 0; }
.bk-build__steps { display: grid; border-top: 1px solid var(--line-light); }
.bk-build__steps li { display: grid; grid-template-columns: 9rem minmax(0, 1fr); gap: 1rem; padding: .9rem 0; border-bottom: 1px solid var(--line-light); opacity: .38; transition: opacity .5s var(--ease-out); }
.bk-build__steps li.bk-is-on { opacity: 1; }
.bk-build__key { font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; font-weight: 500; padding-top: .25em; }
.bk-build__desc { font-size: var(--fs-small); line-height: 1.55; color: var(--muted-light); }
.bk-reduced-motion .bk-build__steps li, .bk-motion-failed .bk-build__steps li { opacity: 1; }
.bk-build__figure { display: grid; gap: 1rem; justify-items: center; }
.bk-build__svg { height: min(76vh, 720px); width: auto; max-width: 100%; aspect-ratio: 121.08 / 127.69; fill: var(--navy); overflow: visible; }
.bk-build__svg .bk-p-d, .bk-build__svg .bk-p-r { fill: var(--blue); }
.bk-build__svg .bk-g-line { fill: none; stroke: var(--blue); stroke-width: 1px; vector-effect: non-scaling-stroke; }
.bk-build__svg .bk-g-soft { stroke: var(--gray); }
.bk-build__svg .bk-g-dash { stroke-dasharray: 5 5; }
.bk-build__svg .bk-g-fill { fill: rgba(14,66,120,.08); stroke: none; }
.bk-build__svg .bk-g-ring { fill: none; stroke: var(--blue); stroke-width: 1.5px; vector-effect: non-scaling-stroke; }
.bk-build__svg .bk-g-label { fill: var(--blue); font-family: var(--f-mono); font-size: 2.6px; letter-spacing: .1px; }
.bk-build__svg .bk-g-step { transition: opacity .5s var(--ease-out); }
.bk-motion .bk-build__svg .bk-g-step { opacity: 0; }
.bk-motion .bk-build__svg .bk-g-step.bk-is-on { opacity: 1; }
.bk-build.bk-guides-off .bk-build__svg .bk-g-step { opacity: 0 !important; }
.bk-toggle { justify-self: start; display: inline-flex; align-items: center; gap: .8rem; min-height: 44px; font-weight: 600; font-size: var(--fs-small); }
.bk-toggle__track { width: 44px; height: 24px; border-radius: 99px; border: 1px solid currentColor; position: relative; transition: background-color .3s; }
.bk-toggle__track span { position: absolute; top: 3px; left: 3px; width: 16px; height: 16px; border-radius: 50%; background: currentColor; transition: transform .35s var(--ease-out), background-color .3s; }
.bk-toggle[aria-pressed="true"] .bk-toggle__track { background: var(--navy); border-color: var(--navy); }
.bk-toggle[aria-pressed="true"] .bk-toggle__track span { transform: translateX(20px); background: #fff; }
@media (max-width: 1023px) {
  .bk-build__layout { grid-template-columns: 1fr; }
  .bk-build__svg { height: auto; width: min(100%, 520px); }
  .bk-build__steps li { grid-template-columns: 7rem minmax(0, 1fr); }
}

/* ==========================================================================
   07 — LOGOTYP
   ========================================================================== */
.bk-word { padding-top: var(--sp-xl); overflow: hidden; }
.bk-word__pin { min-height: 100vh; min-height: 100svh; display: grid; align-items: center; padding-block: var(--nav-h) 2rem; }
.bk-word__stage { display: grid; gap: clamp(1.4rem, 4vh, 3rem); padding-inline: var(--gutter); justify-items: center; }
.bk-word__name { width: min(92vw, 1500px); }
.bk-word__name svg, .bk-word__tag svg { overflow: hidden; }
.bk-word__tag { width: min(84vw, 1300px); }
.bk-word__legend { display: flex; justify-content: space-between; gap: 2rem; width: min(92vw, 1500px); font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; color: var(--muted-dark); border-top: 1px solid var(--line-dark); padding-top: 1rem; }
.bk-word__body { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: var(--sp-l); align-items: start; padding-block: var(--sp-l); }
.bk-word__text { display: grid; gap: 1rem; max-width: 46ch; }
.bk-word__text p:not(.bk-lead) { color: var(--muted-dark); }
.bk-lines { display: grid; gap: 1rem; }
.bk-lines__frame { background: var(--navy-deep); box-shadow: inset 0 0 0 1px var(--line-dark); padding: clamp(1rem, 3vw, 2.4rem); }
.bk-lines__svg { width: 100%; height: auto; overflow: visible; }
.bk-lines__svg .bk-cz { fill: rgba(255,255,255,.07); }
.bk-lines__svg .bk-cl { stroke: #8FB3E8; stroke-width: 1px; vector-effect: non-scaling-stroke; opacity: .6; }
.bk-lines__svg .bk-clogo { fill: #fff; }
.bk-word__final { padding-block: var(--sp-l) var(--sp-xl); }
.bk-word__logo { width: min(100%, 980px); margin-inline: auto; }
@media (max-width: 1023px) { .bk-word__body { grid-template-columns: 1fr; } }
@media (max-width: 599px) { .bk-word__legend { flex-direction: column; gap: .4rem; } }

/* ==========================================================================
   08 — TYPOGRAFIA
   ========================================================================== */
.bk-type { padding-top: var(--sp-xl); }
.bk-type__head { padding-bottom: var(--sp-l); }
.bk-type__font { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: var(--sp-l); padding-bottom: var(--sp-xl); align-items: start; }
.bk-type__meta { display: grid; gap: 1.1rem; }
.bk-type__family { font-size: clamp(3rem, 1.6rem + 5vw, 7rem); font-weight: 800; letter-spacing: -0.015em; line-height: .9; }
.bk-type__specs { display: grid; border-top: 1px solid var(--line-light); }
.bk-type__specs div { display: grid; grid-template-columns: 11rem minmax(0, 1fr); gap: 1rem; padding: .75rem 0; border-bottom: 1px solid var(--line-light); font-size: var(--fs-small); }
.bk-type__specs dt { color: var(--muted-light); }
.bk-type__specs dd { font-weight: 600; }
.bk-glyphs { display: grid; gap: var(--sp-m); }
.bk-glyphs__label { font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; color: var(--muted-light); margin-bottom: .8rem; }
.bk-glyphs__row { display: grid; grid-template-columns: repeat(auto-fill, minmax(clamp(52px, 7vw, 84px), 1fr)); border-top: 1px solid var(--line-light); border-left: 1px solid var(--line-light); }
.bk-glyph { position: relative; aspect-ratio: 1; border-right: 1px solid var(--line-light); border-bottom: 1px solid var(--line-light); display: grid; place-items: center; transition: background-color .3s, color .3s; color: var(--navy); }
.bk-glyph svg { width: 56%; height: 56%; fill: currentColor; overflow: visible; }
.bk-glyph:hover { background: var(--navy); color: #fff; }
.bk-glyph__c { position: absolute; left: 5px; top: 3px; font-family: var(--f-mono); font-size: 9px; color: var(--muted-light); }
.bk-glyph:hover .bk-glyph__c { color: rgba(255,255,255,.7); }
@media (max-width: 1023px) { .bk-type__font { grid-template-columns: 1fr; } }
@media (max-width: 479px) { .bk-type__specs div { grid-template-columns: 1fr; gap: .2rem; } }

.bk-type__band { padding-block: var(--sp-xl); }
.bk-type__hier { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr); gap: var(--sp-l); align-items: end; }
.bk-type__hier > .bk-label { grid-column: 1 / -1; }
.bk-hier { display: grid; gap: 1.2rem; }
.bk-hier__h1 { font-size: clamp(3rem, 1.5rem + 6vw, 8.5rem); font-weight: 800; letter-spacing: -0.018em; line-height: .88; }
.bk-hier__h2 { font-size: clamp(1.5rem, 1rem + 1.8vw, 2.8rem); font-weight: 600; letter-spacing: -0.011em; line-height: 1.1; }
.bk-hier__caps { font-size: clamp(.8rem, .7rem + .4vw, 1.05rem); font-weight: 300; letter-spacing: .01em; }
.bk-hier__p { color: var(--muted-dark); max-width: 46ch; }
.bk-charset { display: grid; gap: .5rem; font-size: clamp(1.1rem, .8rem + 1.3vw, 2.2rem); font-weight: 300; letter-spacing: .02em; line-height: 1.25; overflow-wrap: anywhere; }
.bk-charset__row:nth-child(1) { font-weight: 800; letter-spacing: -0.006em; }
.bk-charset__row:nth-child(3) { font-weight: 600; font-variant-numeric: tabular-nums; }
.bk-charset__row--pl { font-weight: 500; }
@media (max-width: 1023px) { .bk-type__hier { grid-template-columns: 1fr; } }

.bk-play { padding-block: var(--sp-xl); display: grid; gap: var(--sp-m); }
.bk-play__head { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr); gap: var(--sp-m); align-items: baseline; }
.bk-play__output {
  display: block; width: 100%; min-height: 2.4em; resize: vertical; border: 0; border-top: 1px solid var(--navy); border-bottom: 1px solid var(--line-light);
  padding: .3em 0; background: transparent; color: var(--navy); font-family: var(--f-sans);
  font-size: var(--play-size, 72px); font-weight: var(--play-weight, 700); letter-spacing: var(--play-track, -0.02em); line-height: 1.05;
  transition: background-color .4s, color .4s, padding .4s; overflow-wrap: anywhere; overflow: hidden;
}
.bk-play__output:focus-visible { outline: 2px solid var(--navy); outline-offset: 6px; }
.bk-play__output.bk-is-caps { }
.bk-play__output.bk-is-invert { background: var(--navy); color: #fff; padding: .3em .35em; }
.bk-play__controls { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)) auto; gap: var(--sp-m); align-items: end; }
.bk-range { display: grid; gap: .5rem; font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; }
.bk-range span { display: flex; justify-content: space-between; }
.bk-range output { font-weight: 500; }
.bk-range input { width: 100%; accent-color: var(--navy); height: 28px; }
.bk-play__switches { display: flex; gap: .5rem; flex-wrap: wrap; }
@media (max-width: 1023px) {
  .bk-play__head { grid-template-columns: 1fr; }
  .bk-play__controls { grid-template-columns: 1fr 1fr; }
  .bk-play__switches { grid-column: 1 / -1; }
}
@media (max-width: 479px) { .bk-play__controls { grid-template-columns: 1fr; } }

/* ==========================================================================
   09 — KOLOR
   ========================================================================== */
.bk-color { background: var(--white); color: var(--ink); }
.bk-color__intro { background: var(--navy); color: #fff; padding-block: calc(var(--sp-xl) + var(--nav-h)) var(--sp-l); }
.bk-color__title { font-size: clamp(3rem, 1.2rem + 7vw, 10rem); max-width: 10ch; }
.bk-color__text { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: var(--sp-l); margin-top: var(--sp-l); max-width: 1100px; }
.bk-color__text p:not(.bk-lead) { color: var(--muted-dark); }
.bk-color__statement { overflow: hidden; background: var(--navy); color: #fff; min-height: 100vh; min-height: 100svh; display: grid; align-items: center; padding: var(--nav-h) var(--pad-x) 2rem; }
.bk-color__big { font-size: clamp(2.6rem, 1rem + 6.6vw, 9.4rem); font-weight: 800; letter-spacing: -0.017em; line-height: .92; }
.bk-color__big span { display: block; }
.bk-color__big span:last-child { font-weight: 200; padding-left: clamp(0rem, 12vw - 4rem, 14rem); }
@media (max-width: 767px) { .bk-color__text { grid-template-columns: 1fr; } }

.bk-color__palette { padding-block: var(--sp-xl) var(--sp-l); display: grid; gap: var(--sp-m); }
.bk-swatches { display: grid; grid-template-columns: 3fr 2fr 1.4fr; gap: 0; }
.bk-swatches--aux { grid-template-columns: 1fr 1fr minmax(0, 1.6fr); align-items: stretch; }
.bk-swatch { position: relative; display: grid; align-content: end; gap: .3rem; text-align: left; min-height: clamp(220px, 40vh, 420px); padding: clamp(1rem, 2vw, 1.8rem); transition: filter .3s; }
.bk-swatches--aux .bk-swatch { min-height: 150px; }
.bk-swatch--navy { background: var(--navy); color: #fff; }
.bk-swatch--blue { background: var(--blue); color: #fff; }
.bk-swatch--white { background: #fff; color: var(--navy); box-shadow: inset 0 0 0 1px var(--line-light); }
.bk-swatch--paper { background: var(--paper); color: var(--navy); }
.bk-swatch--gray { background: var(--gray); color: var(--navy); }
.bk-swatch__role { font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; opacity: .8; margin-bottom: auto; position: absolute; top: clamp(1rem, 2vw, 1.8rem); left: clamp(1rem, 2vw, 1.8rem); }
.bk-swatch__name { font-size: clamp(1.4rem, 1rem + 1.4vw, 2.6rem); font-weight: 700; letter-spacing: -0.011em; line-height: 1; }
.bk-swatch__hex { font-family: var(--f-mono); font-size: clamp(.95rem, .85rem + .3vw, 1.15rem); font-weight: 500; letter-spacing: .04em; }
.bk-swatch__meta { font-size: var(--fs-micro); opacity: .8; }
.bk-swatch__meta i { font-style: normal; opacity: .6; }
.bk-swatch__copy { position: absolute; top: clamp(1rem, 2vw, 1.8rem); right: clamp(1rem, 2vw, 1.8rem); font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; opacity: 0; transform: translateY(4px); transition: opacity .3s, transform .3s var(--ease-out); }
.bk-swatch:hover .bk-swatch__copy, .bk-swatch:focus-visible .bk-swatch__copy { opacity: 1; transform: none; }
.bk-swatch:focus-visible { outline-offset: -6px; }
.bk-swatches__note { padding: 1rem 0 0 clamp(1rem, 2vw, 1.8rem); align-self: end; }
@media (max-width: 767px) {
  .bk-swatches { grid-template-columns: 1fr; }
  .bk-swatch { min-height: 170px; }
  .bk-swatches--aux { grid-template-columns: 1fr 1fr; }
  .bk-swatches__note { grid-column: 1 / -1; padding-left: 0; }
}
.bk-contrast { display: grid; gap: 1rem; margin-top: var(--sp-m); }
.bk-contrast__list { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); border-top: 1px solid var(--line-light); }
.bk-contrast__list li { display: grid; grid-template-columns: auto 1fr; gap: .2rem 1rem; align-items: center; padding: 1rem 1rem 1rem 0; border-bottom: 1px solid var(--line-light); }
.bk-contrast__sample { grid-row: span 2; width: 52px; height: 52px; display: grid; place-items: center; font-weight: 800; font-size: 1.3rem; letter-spacing: -0.009em; }
.bk-contrast__ratio { font-weight: 700; font-size: 1.15rem; letter-spacing: -0.006em; }
.bk-contrast__pass { font-family: var(--f-mono); font-size: var(--fs-micro); color: var(--muted-light); letter-spacing: .04em; }

.bk-color__lab { display: grid; gap: var(--sp-l); padding-block: var(--sp-l) var(--sp-xl); }
.bk-lab { display: grid; grid-template-columns: minmax(0, .7fr) minmax(0, 1.3fr); gap: var(--sp-m); align-items: stretch; }
.bk-lab__copy { display: grid; gap: 1rem; align-content: start; }
.bk-lab__title { font-size: var(--fs-h3); font-weight: 700; letter-spacing: -0.009em; line-height: 1.1; }
.bk-seg { display: inline-flex; border: 1px solid var(--navy); border-radius: 99px; padding: 3px; justify-self: start; }
.bk-seg button { min-height: 40px; padding: 0 1.2rem; border-radius: 99px; font-weight: 600; font-size: var(--fs-small); transition: background-color .35s, color .35s; }
.bk-seg button[aria-checked="true"] { background: var(--navy); color: #fff; }
.bk-lab__preview { display: grid; place-items: center; min-height: clamp(220px, 34vw, 420px); padding: clamp(1.5rem, 5vw, 4rem); background: #fff; box-shadow: inset 0 0 0 1px var(--line-light); transition: background-color .7s var(--ease-io); }
.bk-lab__preview.bk-is-dark { background: var(--navy); --lg-sign: #fff; --lg-sign2: #fff; --lg-name: #fff; --lg-tag: #fff; }
.bk-lab__logo { width: min(100%, 560px); }
.bk-lab__logo path, .bk-sv path, .bk-icon path { transition: fill .7s var(--ease-io); }
@media (max-width: 767px) { .bk-lab { grid-template-columns: 1fr; } }

.bk-variants { display: grid; gap: var(--sp-m); }
.bk-variants__head { display: grid; grid-template-columns: minmax(0, .7fr) minmax(0, 1.3fr); gap: var(--sp-m); align-items: baseline; }
.bk-variants__text { color: var(--muted-light); max-width: 56ch; }
.bk-variants__grid { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 0; border-top: 1px solid var(--line-light); border-left: 1px solid var(--line-light); }
.bk-variant { position: relative; display: grid; gap: .8rem; justify-items: center; padding: clamp(1rem, 2vw, 1.8rem) .6rem 1rem; border-right: 1px solid var(--line-light); border-bottom: 1px solid var(--line-light); transition: opacity .4s; }
.bk-variant__sign { width: clamp(34px, 4.6vw, 64px); }
.bk-variant__dots { display: flex; gap: 6px; }
.bk-variant__dots i { width: 14px; height: 14px; border-radius: 50%; }
.bk-variant__hex { font-family: var(--f-mono); font-size: 10px; letter-spacing: .02em; color: var(--muted-light); text-align: center; line-height: 1.5; }
.bk-variant__badge { position: absolute; top: .5rem; left: .5rem; font-family: var(--f-mono); font-size: 9px; letter-spacing: .01em; background: var(--navy); color: #fff; padding: .15rem .4rem; }
.bk-variants__grid:hover .bk-variant:not(:hover) { opacity: .55; }
.bk-variant.bk-is-chosen { background: var(--paper); }
@media (max-width: 1023px) { .bk-variants__grid { grid-template-columns: repeat(3, minmax(0, 1fr)); } .bk-variants__head { grid-template-columns: 1fr; } }

/* ==========================================================================
   10 — SYSTEM LOGO
   ========================================================================== */
.bk-system { background: #fff; color: var(--navy); transition: background-color .8s var(--ease-io), color .8s var(--ease-io); }
.bk-system[data-bg="navy"] { background: var(--navy); color: #fff; }
.bk-system[data-bg="paper"] { background: var(--paper); }
.bk-system__pin { min-height: 100vh; min-height: 100svh; display: grid; align-items: center; padding-block: calc(var(--nav-h) + 2rem) 3rem; }
.bk-system__layout { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: var(--sp-l); align-items: center; }
.bk-system__copy { display: grid; gap: var(--sp-m); }
.bk-system__copy .bk-eyebrow { margin-bottom: 0; }
.bk-system__tabs { display: grid; border-top: 1px solid currentColor; border-color: rgba(127,138,170,.35); }
.bk-system__tabs button { display: flex; gap: 1rem; align-items: baseline; text-align: left; min-height: 44px; padding: .55rem 0; border-bottom: 1px solid rgba(127,138,170,.35); font-weight: 600; opacity: .5; transition: opacity .35s, padding .4s var(--ease-out); }
.bk-system__tabs button span { font-family: var(--f-mono); font-size: var(--fs-micro); font-weight: 400; }
.bk-system__tabs button:hover { opacity: .85; }
.bk-system__tabs button[aria-selected="true"] { opacity: 1; padding-left: .6rem; }
.bk-system__desc { font-size: var(--fs-small); line-height: 1.55; opacity: .82; min-height: 4.8em; max-width: 46ch; }
.bk-system__stage { position: relative; aspect-ratio: 4 / 3; overflow: hidden; }
.bk-sv { position: absolute; inset: 0; display: grid; place-items: center; padding: clamp(1.4rem, 5vw, 4.5rem); opacity: 0; visibility: hidden; transition: opacity .7s var(--ease-out), visibility .7s; }
.bk-sv.bk-is-active { opacity: 1; visibility: visible; }
.bk-sv--h, .bk-sv--sign, .bk-sv--stack, .bk-sv--icons { --lg-sign: var(--navy); --lg-sign2: var(--blue); --lg-name: var(--navy); --lg-tag: var(--blue); }
.bk-sv--h { background: #fff; box-shadow: inset 0 0 0 1px var(--line-light); }
.bk-sv--neg { background: var(--navy); --lg-sign: #fff; --lg-sign2: #fff; --lg-name: #fff; --lg-tag: #fff; box-shadow: inset 0 0 0 1px var(--line-dark); }
.bk-sv--sign { background: var(--paper); }
.bk-sv--pattern { background: var(--navy); overflow: hidden; --lg-sign: #fff; --lg-sign2: #fff; --lg-name: #fff; --lg-tag: #fff; }
.bk-sv--stack { background: #fff; box-shadow: inset 0 0 0 1px var(--line-light); }
.bk-sv--icons { background: var(--paper); }
.bk-sv--clear { background: #fff; box-shadow: inset 0 0 0 1px var(--line-light); }
.bk-sv__logo { width: min(100%, 560px); }
.bk-sv__logo--small { position: relative; width: min(70%, 380px); }
.bk-sv__sign { height: 74%; width: auto; aspect-ratio: 43.28 / 69.55; }
.bk-sv__sign svg { height: 100%; width: auto; }
.bk-sv__pattern { position: absolute; inset: 0; }
.bk-sv__pattern svg { position: absolute; height: 190%; width: auto; max-width: none; left: 34%; top: -50%; fill: rgba(255,255,255,.06); }
.bk-sv__stack { width: min(52%, 300px); }
.bk-sv__clear { width: 100%; height: auto; overflow: visible; }
.bk-sv__clear .bk-cz { fill: rgba(14,66,120,.09); }
.bk-sv__clear .bk-cl { stroke: var(--blue); stroke-width: 1px; vector-effect: non-scaling-stroke; opacity: .5; }
.bk-sv__clear .bk-clogo { fill: var(--navy); }
/* Ikony jak w pierwszym rzędzie mockupu telefonu: kwadrat z zaokrąglonymi rogami, sygnet ~60% wysokości */
.bk-icons { display: flex; flex-wrap: wrap; justify-content: center; gap: clamp(.9rem, 3vw, 2.4rem); }
.bk-icon { flex: none; width: clamp(76px, 11vw, 150px); height: clamp(76px, 11vw, 150px); border-radius: 22%; display: flex; align-items: center; justify-content: center; box-shadow: 0 14px 34px rgba(10,30,87,.16), 0 0 0 1px rgba(10,30,87,.06); }
.bk-icon__sign { height: 62%; aspect-ratio: 43.28 / 69.55; }
.bk-icon__sign svg { width: 100%; height: 100%; }
.bk-icon--navy { background: var(--navy); --lg-sign: #fff; --lg-sign2: #fff; }
.bk-icon--blue { background: var(--blue); --lg-sign: #fff; --lg-sign2: #fff; }
.bk-icon--white { background: #fff; }
@media (max-width: 1023px) {
  .bk-system__layout { grid-template-columns: 1fr; }
  .bk-system__tabs { grid-template-columns: 1fr 1fr; column-gap: 1.2rem; }
}
@media (max-width: 479px) { .bk-system__tabs { grid-template-columns: 1fr; } .bk-system__stage { aspect-ratio: 1 / 1; } }

/* ==========================================================================
   11 — MARKA W DZIAŁANIU
   ========================================================================== */
.bk-action { padding-top: var(--sp-xl); overflow: hidden; }
.bk-action__head { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr); column-gap: var(--sp-l); align-items: end; padding-bottom: var(--sp-l); }
.bk-action__head .bk-eyebrow { grid-column: 1 / -1; }
.bk-action__intro { color: var(--muted-light); max-width: 44ch; }
.bk-gallery { position: relative; padding-bottom: var(--sp-xl); }
.bk-gallery__track { display: flex; gap: clamp(14px, 2vw, 32px); padding-inline: var(--pad-x); overflow-x: auto; scroll-snap-type: x mandatory; scrollbar-width: none; -webkit-overflow-scrolling: touch; }
.bk-gallery__track::-webkit-scrollbar { display: none; }
.bk-shot { flex: 0 0 auto; width: min(86vw, 1000px); scroll-snap-align: center; }
.bk-shot figure { display: grid; gap: .9rem; }
.bk-shot__media { position: relative; overflow: hidden; background: var(--bg); aspect-ratio: 4 / 3; }
.bk-shot__media img { width: 100%; height: 100%; object-fit: cover; }
.bk-shot figcaption { display: flex; gap: 1rem; font-size: var(--fs-small); font-weight: 600; }
.bk-shot figcaption span { font-family: var(--f-mono); font-weight: 400; color: var(--muted-light); }
.bk-gallery__bar { margin: 1.6rem var(--pad-x) 0; height: 1px; background: var(--line-light); }
.bk-gallery__bar span { display: block; height: 100%; background: var(--navy); transform-origin: 0 50%; transform: scaleX(0); }
.bk-gallery.bk-is-pinned { padding-bottom: 0; height: 100vh; height: 100svh; display: grid; align-content: center; padding-top: var(--nav-h); }
.bk-gallery.bk-is-pinned .bk-gallery__track { overflow: visible; scroll-snap-type: none; width: max-content; }
.bk-gallery.bk-is-pinned .bk-shot { width: min(62vw, calc((100svh - var(--nav-h) - 7rem) * 4 / 3)); }
@media (max-width: 1023px) { .bk-action__head { grid-template-columns: 1fr; row-gap: 1.2rem; } }

/* ==========================================================================
   12 — TOŻSAMOŚĆ CYFROWA
   ========================================================================== */
.bk-digital { padding-block: var(--sp-xl); }
.bk-digital__head { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr); column-gap: var(--sp-l); align-items: end; padding-bottom: var(--sp-l); }
.bk-digital__head .bk-eyebrow { grid-column: 1 / -1; }
.bk-digital__intro { color: var(--muted-light); max-width: 46ch; }
@media (max-width: 1023px) { .bk-digital__head { grid-template-columns: 1fr; row-gap: 1.2rem; } }
.bk-tagline { display: flex; flex-wrap: wrap; align-items: center; gap: .4rem 1rem; font-size: var(--fs-small); font-weight: 600; margin-top: .9rem; }
.bk-tagline__src { font-family: var(--f-mono); font-size: 10px; font-weight: 500; letter-spacing: .01em; padding: .2rem .5rem; background: var(--navy); color: #fff; }
.bk-tagline__src--concept { background: transparent; color: var(--navy); box-shadow: inset 0 0 0 1px var(--navy); }
.bk-browser { background: #fff; box-shadow: 0 30px 80px rgba(10,30,87,.14), 0 0 0 1px var(--line-light); overflow: hidden; }
.bk-browser__bar { display: flex; align-items: center; gap: 6px; height: 34px; padding: 0 14px; background: var(--paper); border-bottom: 1px solid var(--line-light); }
.bk-browser__bar i { width: 9px; height: 9px; border-radius: 50%; background: var(--gray); opacity: .6; }
.bk-browser__bar span { margin-left: 14px; font-family: var(--f-mono); font-size: 11px; color: var(--muted-light); }
.bk-browser img { width: 100%; }

.bk-concepts { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: clamp(1rem, 2.4vw, 2.4rem); margin-top: var(--sp-l); }
.bk-concept { min-width: 0; }
.bk-concept--slide { grid-column: span 4; }
.bk-concept--talk { grid-column: span 2; }
.bk-concept--article, .bk-concept--profile, .bk-concept--edu { grid-column: span 2; }
@media (max-width: 1023px) {
  .bk-concepts { grid-template-columns: 1fr 1fr; }
  .bk-concept--slide { grid-column: 1 / -1; }
  .bk-concept--talk, .bk-concept--article, .bk-concept--profile, .bk-concept--edu { grid-column: span 1; }
}
@media (max-width: 599px) { .bk-concepts { grid-template-columns: 1fr; } .bk-concept { grid-column: 1 / -1 !important; } }

.bk-slide { position: relative; aspect-ratio: 16 / 9; background: var(--navy); color: #fff; padding: clamp(1.2rem, 3.4vw, 3rem); display: grid; align-content: end; gap: .6rem; overflow: hidden; container-type: inline-size; --lg-sign: #fff; --lg-sign2: #fff; }
.bk-slide__sign { position: absolute; right: -4%; top: -14%; height: 150%; width: auto; aspect-ratio: 43.28 / 69.55; opacity: .1; }
.bk-slide__sign svg { height: 100%; width: auto; }
.bk-slide__kicker { font-family: var(--f-mono); font-size: max(10px, 1.6cqw); letter-spacing: .01em; opacity: .75; }
.bk-slide__title { font-size: max(1.4rem, 6.4cqw); font-weight: 800; letter-spacing: -0.013em; line-height: .95; max-width: 12ch; }
.bk-slide__meta { display: flex; flex-wrap: wrap; gap: .2rem 1.4rem; font-size: max(11px, 1.5cqw); margin-top: .6rem; padding-top: .8rem; border-top: 1px solid rgba(255,255,255,.25); }
.bk-slide__meta span:first-child { font-weight: 700; }
.bk-slide__meta span:last-child { font-weight: 300; letter-spacing: .01em; }
.bk-slide__num { position: absolute; left: clamp(1.2rem, 3.4vw, 3rem); top: clamp(1.2rem, 3vw, 2.6rem); font-family: var(--f-mono); font-size: max(10px, 1.4cqw); opacity: .7; }

.bk-talk { height: 100%; min-height: 100%; aspect-ratio: auto; background: var(--paper); padding: clamp(1.2rem, 2.4vw, 2rem); display: grid; grid-template-rows: auto 1fr auto; gap: 1rem; }
.bk-concept--talk { display: grid; grid-template-rows: 1fr auto; }
.bk-talk__top { display: flex; align-items: center; justify-content: space-between; font-family: var(--f-mono); font-size: 10px; letter-spacing: .01em; }
.bk-talk__sign { width: 22px; }
.bk-talk__title { font-size: clamp(1.4rem, 1rem + 1.2vw, 2.1rem); font-weight: 700; letter-spacing: -0.012em; line-height: 1.02; align-self: center; }
.bk-talk__meta { display: grid; border-top: 1px solid var(--navy); }
.bk-talk__meta div { display: flex; justify-content: space-between; gap: 1rem; padding: .55rem 0; border-bottom: 1px solid var(--line-light); font-size: var(--fs-small); }
.bk-talk__meta dt { color: var(--muted-light); }
.bk-talk__meta dd { font-weight: 600; text-align: right; }

.bk-article { background: #fff; box-shadow: 0 0 0 1px var(--line-light); padding: 0 1.3rem 1.4rem; display: grid; gap: .7rem; aspect-ratio: 4 / 5; align-content: start; overflow: hidden; }
.bk-article__bar { display: flex; justify-content: space-between; align-items: center; padding: 1rem 0; border-bottom: 1px solid var(--line-light); margin-bottom: .6rem; }
.bk-article__logo { width: 120px; }
.bk-article__nav { display: flex; gap: 6px; }
.bk-article__nav i { width: 18px; height: 2px; background: var(--navy); opacity: .5; }
.bk-article__cat { font-family: var(--f-mono); font-size: 10px; letter-spacing: .01em; color: var(--blue); }
.bk-article__title { font-size: clamp(1.3rem, 1rem + .9vw, 1.8rem); font-weight: 800; letter-spacing: -0.012em; line-height: 1.02; }
.bk-article__lead { font-size: var(--fs-small); line-height: 1.5; color: var(--muted-light); }
.bk-article__lines { display: grid; gap: 9px; margin-top: .4rem; }
.bk-article__lines i { height: 6px; background: var(--paper); }
.bk-article__lines i:nth-child(3n+2) { width: 92%; } .bk-article__lines i:nth-child(4n) { width: 76%; } .bk-article__lines i:last-child { width: 48%; }

.bk-profile { position: relative; background: #fff; box-shadow: 0 0 0 1px var(--line-light); aspect-ratio: 4 / 5; display: flex; flex-direction: column; align-items: center; text-align: center; overflow: hidden; padding-bottom: 1.4rem; }
.bk-profile__cover { flex: none; width: 100%; aspect-ratio: 2.2 / 1; background: var(--navy); overflow: hidden; position: relative; --lg-sign: rgba(255,255,255,.14); --lg-sign2: rgba(255,255,255,.14); }
.bk-profile__cover span { position: absolute; right: 6%; top: -45%; height: 200%; width: auto; aspect-ratio: 43.28 / 69.55; }
.bk-profile__cover svg { height: 100%; width: auto; }
.bk-profile__avatar { flex: none; width: 30%; aspect-ratio: 1; border-radius: 50%; background: #fff; box-shadow: 0 0 0 4px #fff, 0 0 0 5px var(--line-light); margin-top: -15%; position: relative; display: grid; place-items: center; }
.bk-profile__avatar span { width: 30%; }
.bk-profile__name { margin-top: 1rem; font-weight: 800; font-size: 1.2rem; letter-spacing: -0.009em; }
.bk-profile__role { font-size: 10px; letter-spacing: .01em; color: var(--blue); margin-top: .2rem; }
.bk-profile__btn { margin-top: 1.1rem; padding: .5rem 1.4rem; background: var(--navy); color: #fff; font-size: var(--fs-small); font-weight: 600; }
.bk-profile__lines { display: grid; gap: 8px; width: 70%; margin-top: auto; }
.bk-profile__lines i { height: 6px; background: var(--paper); }
.bk-profile__lines i:last-child { width: 70%; justify-self: center; }

.bk-edu { background: var(--navy); color: #fff; aspect-ratio: 4 / 5; padding: 1.3rem; display: grid; grid-template-rows: auto 1fr auto; gap: 1rem; --lg-sign: #fff; --lg-sign2: #fff; --lg-name: #fff; --lg-tag: #fff; }
.bk-edu__head { display: flex; justify-content: space-between; align-items: center; gap: 1rem; font-family: var(--f-mono); font-size: 10px; letter-spacing: .01em; opacity: .9; padding-bottom: 1rem; border-bottom: 1px solid rgba(255,255,255,.22); }
.bk-edu__logo { width: 110px; }
.bk-edu__title { font-size: clamp(1.3rem, 1rem + .9vw, 1.8rem); font-weight: 800; letter-spacing: -0.012em; line-height: 1.05; align-self: center; }
.bk-edu__list { display: grid; counter-reset: e; }
.bk-edu__list li { counter-increment: e; display: flex; gap: .8rem; padding: .5rem 0; border-top: 1px solid rgba(255,255,255,.22); font-size: var(--fs-small); }
.bk-edu__list li::before { content: "0" counter(e); font-family: var(--f-mono); font-size: 10px; opacity: .7; padding-top: .2em; }

/* ==========================================================================
   13 — FINAŁ
   ========================================================================== */
.bk-final { overflow: hidden; }
.bk-final__pin { position: relative; min-height: 100vh; min-height: 100svh; display: grid; place-items: center; padding: var(--nav-h) var(--gutter) 2rem; overflow: hidden; }
.bk-final__pattern svg { left: -18%; right: auto; top: -30%; }
.bk-final__stage { position: relative; z-index: 1; width: 100%; display: grid; place-items: center; }
.bk-final__logo { width: min(86vw, 1100px); }
.bk-final__outro { display: grid; gap: var(--sp-m); padding-block: var(--sp-l) var(--sp-xl); position: relative; z-index: 1; }
.bk-final__title { font-size: var(--fs-h2); font-weight: 800; letter-spacing: -0.015em; line-height: .95; max-width: 14ch; }
.bk-final__story { font-size: var(--fs-lead); line-height: 1.55; color: var(--muted-dark); max-width: 58ch; }
.bk-final__tags { display: flex; flex-wrap: wrap; gap: .6rem; margin-top: .6rem; }
.bk-final__tags li { padding: .5rem 1rem; border: 1px solid var(--line-dark); font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; }
.bk-final__claim { margin-top: var(--sp-m); padding-top: var(--sp-m); border-top: 1px solid var(--line-dark); font-size: clamp(1.2rem, .9rem + 1vw, 1.9rem); font-weight: 300; letter-spacing: -0.006em; }
.bk-to-top { justify-self: start; display: inline-flex; align-items: center; gap: .7rem; min-height: 48px; padding: 0 1.4rem; border-radius: 99px; box-shadow: inset 0 0 0 1px #fff; text-decoration: none; font-family: var(--f-mono); font-size: var(--fs-micro); letter-spacing: .01em; transition: background-color .35s, color .35s; }
.bk-to-top:hover { background: #fff; color: var(--navy); }

/* ---------- Animacje wejścia (stan startowy tylko w trybie ruchu) ---------- */
.bk-motion [data-bk-reveal], .bk-motion [data-stagger] > *, .bk-motion [data-hero-reveal] { opacity: 0; transform: translateY(26px); }
.bk-motion .bk-hero__logo { opacity: 0; }
.bk-motion .bk-split-ready [data-split] .bk-w > span, .bk-motion [data-split].bk-split-ready .bk-w > span { transform: translateY(135%); }
.bk-w { display: inline-block; overflow: hidden; vertical-align: top; padding: .14em 0 .1em; margin: -.14em 0 -.1em; }
.bk-w > span { display: inline-block; }
.bk-motion-failed [data-bk-reveal], .bk-motion-failed [data-stagger] > *, .bk-motion-failed [data-hero-reveal], .bk-motion-failed .bk-hero__logo { opacity: 1 !important; transform: none !important; }
.bk-motion-failed [data-split] .bk-w > span { transform: none !important; }

/* ---------- Ograniczony ruch ---------- */
@media (prefers-reduced-motion: reduce) {
  :where(.bk) *, :where(.bk) *::before, :where(.bk) *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; scroll-behavior: auto !important; }
}
.bk-reduced-motion .bk-scroll-cue__line::after { animation: none; }
.bk-system .bk-h2, .bk-build .bk-h2, .bk-mono .bk-h2, .bk-idea .bk-h2 { font-size: clamp(2.1rem, 1rem + 3vw, 4.6rem); }
@media (max-width: 599px) {
  .bk-hero .bk-eyebrow__label { display: none; }
  .bk-hero .bk-eyebrow__num::after { display: none; }
}

/* ==========================================================================
   WD Design — dopasowanie do strony (generator build-marekborowinski.cjs, 1.24.48)
   ========================================================================== */
.bk { position: relative; overflow-x: clip; }
/* Nagłówki rozdziałów w kroju nagłówków strony (Nohemi ma 400/500 — 500 zamiast 700–800 ze źródła). */
.bk-h2, .bk-final__title, .bk-duo__claim, .bk-values__claim, .bk-lab__title, .bk-menu__list a { font-family: var(--f-head); font-weight: 500; letter-spacing: -0.011em; }
/* Pokaz pisma: podpis „wersaliki” i przełącznik w testerze mają pokazywać wersaliki. */
.bk-hier__caps { text-transform: uppercase; letter-spacing: .32em; }
.bk-play__output.bk-is-caps { text-transform: uppercase; }
/* Pasek rozdziałów i menu: tuż pod DOLNĄ krawędzią nagłówka strony (--bar-top liczy skrypt — uwzględnia
   pasek administratora WordPressa). Pasek zostaje nad otwartym menu, „Rozdziały” zamienia się w „Zamknij”. */
.bk-site-header { inset: var(--bar-top, var(--site-offset)) 0 auto 0; }
.bk-menu { inset: calc(var(--bar-top, var(--site-offset)) + var(--header-h)) 0 0 0; }
.bk-menu__inner { padding-top: 1.1rem; }
.bk-menu-open .bk-site-header { z-index: 160; color: var(--white); }
.bk-menu-open .bk-site-header::before { opacity: 1; background: var(--navy-deep); border-bottom-color: var(--line-dark); }
.bk-menu-btn__icon i { transition: transform .4s var(--ease-out); }
.bk-menu-btn[aria-expanded="true"] .bk-menu-btn__icon i:first-child { transform: translateY(2px) rotate(45deg); }
.bk-menu-btn[aria-expanded="true"] .bk-menu-btn__icon i:last-child { transform: translateY(-2px) rotate(-45deg); }
.bk-menu-btn[aria-expanded="true"]:hover .bk-menu-btn__icon { transform: none; }
/* Silnik ruchu motywu dzieli h2 na słowa — tu robi to skrypt case study. */
.bk h2 .sm-w { display: inline; }
/* Reguły motywu dla H1 stron (H1 35 px na telefonie) nie dotyczą okładki księgi. */
@media (max-width: 720px) {
  main .bk h1.bk-hero__title { font-size: var(--fs-hero) !important; line-height: .9 !important; }
}
/* Finał: dwa przyciski (realizacje i wycena). */
.bk-final__actions { display: flex; flex-wrap: wrap; gap: .75rem; justify-self: start; }
.bk-to-top--solid { background: #fff; color: var(--navy); }
.bk-to-top--solid:hover { background: transparent; color: #fff; }
/* Nohemi ma w motywie tylko 400/500 — bez sztucznego pogrubiania (litery zlewały się w hero). */
.bk { font-synthesis-weight: none; }
/* Warianty barwne: miejsce na znacznik „Wybrany” nad znakiem (na telefonie nachodził na sygnet). */
.bk-variant { padding-top: 2.6rem; }
/* Telefon: bez nazwy rozdziału w pasku — kreska prowadziła donikąd. */
@media (max-width: 599px) { .bk-site-header__sep { display: none; } }
/* Hierarchia (rozdział 08): więcej oddechu między nagłówkiem a śródtytułem. */
.bk-hier__h1 { line-height: .95; }
.bk-hier__h1 + .bk-hier__h2 { margin-top: clamp(.5rem, .2rem + 1.2vw, 1.5rem); }