/* ==========================================================================
   Thousand Herbs — Brand Identity Case Study · WD Design
   ========================================================================== */


/* ---------- Tokens ---------- */
.bk {
  /* Height of the main WD Design site header that sits above the chapter bar — adjust to the real site. */
  --site-offset: 72px;

  /* WD Design interface */
  --wd-bg: #050706;
  --wd-surface: #0D1210;
  --wd-surface-2: #151C18;
  --wd-text: #F2EFE9;
  --wd-muted: #A7B3AB;
  --wd-accent: #4BCC6B;
  --wd-accent-soft: #91EDA7;

  /* Thousand Herbs — brand book */
  --th-green: #1A3C34;
  --th-gold: #C5A065;
  --th-ivory: #F2EFE9;
  --th-g2: #3A574F; --th-g3: #5A726B; --th-g4: #7A8D86; --th-g5: #9AA7A1; --th-g6: #BAC2BC; --th-g7: #DADDD8;
  --th-au2: #CDAD79; --th-au3: #D4B98E; --th-au4: #DCC6A2; --th-au5: #E3D2B6; --th-au6: #EBDFCA; --th-au7: #F2EBDF;

  --font-display: "Nohemi", sans-serif;
  --font-text: "Manrope", sans-serif;

  --fs-mega: clamp(2.5rem, min(10.6vw, 21svh), 11.8rem); /* "THOUSAND" ≈ 4.5em wide; height-capped so the hero fits under both headers */
  --fs-display: clamp(2.3rem, 4.9vw, 5.5rem);
  --fs-display-md: clamp(2.1rem, 4.3vw, 4.7rem);
  --fs-h3: clamp(1.5rem, 2.3vw, 2.25rem);
  --fs-lead: clamp(1.125rem, 1.45vw, 1.4rem);
  --fs-body: clamp(1rem, 1.05vw, 1.0625rem);
  --fs-meta: 0.8125rem;

  --gutter: clamp(16px, 4.2vw, 72px);
  --maxw: 1720px;
  --section-y: clamp(96px, 13vw, 220px);
  --header-h: 52px;
  --chrome-h: calc(var(--site-offset) + var(--header-h));

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --dur: 0.6s;

  --radius: 2px;
}

/* ---------- Section themes ---------- */
:where(.bk) [data-theme="dark"] { --bg: var(--wd-bg);        --fg: var(--wd-text); --muted: var(--wd-muted); --line: rgba(242,239,233,.12); --tint: var(--th-gold); --card: var(--wd-surface); }
:where(.bk) [data-theme="surface"] { --bg: var(--wd-surface);   --fg: var(--wd-text); --muted: var(--wd-muted); --line: rgba(242,239,233,.12); --tint: var(--th-gold); --card: var(--wd-surface-2); }
:where(.bk) [data-theme="green"] { --bg: var(--th-green);     --fg: var(--th-ivory); --muted: var(--th-g6);   --line: rgba(242,239,233,.18); --tint: var(--th-gold); --card: rgba(5,7,6,.16); }
:where(.bk) [data-theme="cream"] { --bg: var(--th-ivory);     --fg: var(--th-green); --muted: var(--th-g2);   --line: rgba(26,60,52,.16);    --tint: #8a6a37;        --card: #EAE5DB; }
:where(.bk) [data-theme="photo-light"] { --bg: #E9E1D3; --fg: var(--th-green); --muted: var(--th-g2); --line: rgba(26,60,52,.16); --tint: #8a6a37; --card: #EAE5DB; }
:where(.bk) [data-theme="photo"] { --bg: var(--wd-bg);        --fg: var(--wd-text); --muted: var(--wd-muted); --line: rgba(242,239,233,.2);  --tint: var(--th-gold); --card: var(--wd-surface); }

/* ---------- Base ---------- */
: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-padding-top: calc(var(--site-offset) + var(--header-h)); }
html.bk-page:focus-within { scroll-behavior: smooth; }
.bk {
  margin: 0;
  background: var(--wd-bg);
  color: var(--wd-text);
  font-family: var(--font-text);
  font-size: var(--fs-body);
  line-height: 1.6;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}
:where(.bk) img, :where(.bk) svg { display: block; max-width: 100%; }
:where(.bk) svg { fill: currentColor; }
:where(.bk) img { height: auto; }
:where(.bk) button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
:where(.bk) a { color: inherit; }
:where(.bk) p { margin: 0 0 1em; }
:where(.bk) p:last-child { margin-bottom: 0; }
:where(.bk) h1, :where(.bk) h2, :where(.bk) h3 { margin: 0; font-weight: 400; }
:where(.bk) ol, :where(.bk) ul { margin: 0; padding: 0; list-style: none; }
:where(.bk) dl, :where(.bk) dd, :where(.bk) figure, :where(.bk) blockquote { margin: 0; }
:where(.bk) ::selection { background: var(--th-gold); color: var(--th-green); }

:where(.bk) :focus-visible {
  outline: 2px solid var(--wd-accent);
  outline-offset: 3px;
  border-radius: 2px;
}

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

.bk-skip-link {
  position: fixed; left: 16px; top: 12px; z-index: 200;
  padding: 10px 16px; background: var(--wd-accent); color: var(--wd-bg);
  font-weight: 600; font-size: 14px; text-decoration: none;
  transform: translateY(-160%); transition: transform .3s var(--ease);
}
.bk-skip-link:focus-visible { transform: none; }

/* Film grain — static, cheap */
.bk::after {
  content: "";
  position: fixed; inset: -50%;
  z-index: 150;
  pointer-events: none;
  opacity: .055;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='220' height='220'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 .9 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

.bk-container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* ---------- Typography primitives ---------- */
.bk-meta {
  font-family: var(--font-text);
  font-size: var(--fs-meta);
  font-weight: 500;
  letter-spacing: .01em;
  line-height: 1.5;
  color: var(--muted, var(--wd-muted));
  margin: 0;
}
.bk-eyebrow {
  display: flex; align-items: center; gap: 14px;
  font-size: var(--fs-meta); font-weight: 500;
  letter-spacing: .01em;
  color: var(--muted);
  margin: 0 0 clamp(28px, 3.2vw, 52px);
}
.bk-eyebrow__num {
  font-variant-numeric: tabular-nums;
  color: var(--tint);
  display: inline-flex; align-items: center; gap: 14px;
}
.bk-eyebrow__num::after { content: ""; width: 36px; height: 1px; background: currentColor; opacity: .7; }

.bk-display {
  font-family: var(--font-display);
  font-size: var(--fs-display);
  font-weight: 400;
  line-height: .98;
  letter-spacing: -.035em;
  color: var(--fg);
  text-wrap: balance;
}
.bk-display--md { font-size: var(--fs-display-md); }
.bk-h3 { font-family: var(--font-display); font-size: var(--fs-h3); line-height: 1.1; letter-spacing: -.02em; margin-bottom: .7em; }
.bk-lead {
  font-size: var(--fs-lead);
  line-height: 1.5;
  font-weight: 300;
  letter-spacing: -.01em;
  color: var(--fg);
  max-width: 34em;
  text-wrap: pretty;
}
.bk-note { margin-top: clamp(40px, 5vw, 72px); font-size: 13px; color: var(--muted); max-width: 46em; }


/* Split-line reveal (built by JS) */
.bk-split-line { display: inline-block; overflow: hidden; vertical-align: top; padding: .12em 0 .14em; margin: -.12em 0 -.14em; }
.bk-split-line__in { display: inline-block; will-change: transform; }

/* ---------- Chapters ---------- */
.bk-chapter, .bk-interlude {
  position: relative;
  background: var(--bg);
  color: var(--fg);
}
.bk-chapter { padding-block: var(--section-y); }
.bk-chapter__head { margin-bottom: clamp(56px, 8vw, 128px); max-width: 1180px; }
.bk-chapter__head--split {
  max-width: none;
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: clamp(32px, 6vw, 120px);
  align-items: end;
}
.bk-chapter__head--split .bk-lead { justify-self: end; padding-bottom: .4em; }

/* ---------- Progress & header ---------- */
.bk-progress {
  position: fixed; inset: auto 0 0 0; height: 2px; z-index: 120;
  background: rgba(242,239,233,.06);
  pointer-events: none;
}
.bk-progress__bar {
  display: block; height: 100%;
  background: var(--wd-accent);
  transform-origin: 0 50%;
  transform: scaleX(0);
}

/* Chapter bar — sits directly under the main site header (offset by --site-offset). */
.bk-site-header {
  position: fixed; inset: var(--site-offset) 0 auto 0; z-index: 110;
  height: var(--header-h);
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 16px;
  padding-inline: var(--gutter);
  color: var(--wd-text);
  transition: color .5s var(--ease), transform .5s var(--ease);
}
.bk-site-header::before {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background: rgba(5,7,6,.72);
  -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(242,239,233,.08);
  transition: background-color .5s var(--ease), border-color .5s var(--ease);
}
.bk-site-header[data-nav-theme="light"] { color: var(--th-green); }
.bk-site-header[data-nav-theme="light"]::before { background: rgba(242,239,233,.8); border-bottom-color: rgba(26,60,52,.1); }
.bk-site-header.bk-is-hidden { transform: translateY(calc(-100% - 2px)); opacity: 0; pointer-events: none; }

.bk-site-header__chapter {
  margin: 0; min-width: 0; overflow: hidden;
  display: flex; align-items: center; gap: 12px;
  font-size: 12px; letter-spacing: .01em;
  white-space: nowrap;
}
.bk-site-header__num { font-variant-numeric: tabular-nums; font-weight: 600; }
.bk-site-header__sep { width: 24px; height: 1px; background: currentColor; opacity: .5; }
.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: 40px; padding: 0 4px 0 14px;
  font-size: 12px; letter-spacing: .01em; font-weight: 500;
}
.bk-menu-btn__icon { position: relative; width: 28px; height: 28px; border: 1px solid currentColor; border-radius: 50%; opacity: .9; transition: transform .5s var(--ease); }
.bk-menu-btn__icon i { position: absolute; left: 8px; right: 8px; height: 1px; background: currentColor; transition: transform .4s var(--ease); }
.bk-menu-btn__icon i:first-child { top: 11px; }
.bk-menu-btn__icon i:last-child { top: 15px; }
.bk-menu-btn:hover .bk-menu-btn__icon { transform: rotate(90deg); }

/* ---------- Side rail ---------- */
.bk-rail {
  position: fixed; right: clamp(14px, 1.6vw, 28px); top: 50%; z-index: 100;
  transform: translateY(-50%);
  display: none;
  color: var(--wd-text);
  transition: color .5s var(--ease);
}
.bk-rail[data-nav-theme="light"] { color: var(--th-green); }
.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: 22px;
  text-decoration: none;
}
.bk-rail__tick {
  width: 10px; height: 1px; background: currentColor; opacity: .38;
  transition: width .45s var(--ease), opacity .45s var(--ease);
}
.bk-rail__label {
  position: absolute; right: 30px; top: 50%;
  transform: translate(8px, -50%);
  white-space: nowrap;
  font-size: 11px; letter-spacing: .01em;
  opacity: 0; pointer-events: none;
  transition: opacity .35s var(--ease), transform .35s var(--ease);
}
.bk-rail__label b { font-weight: 600; 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; background: var(--wd-accent); }

@media (min-width: 1024px) { .bk-rail { display: block; } }

/* ---------- Menu overlay ---------- */
.bk-menu {
  position: fixed; inset: var(--site-offset) 0 0 0; z-index: 130;
  background: var(--wd-bg);
  color: var(--wd-text);
  overflow-y: auto;
  overscroll-behavior: contain;
}
.bk-menu[hidden] { display: none; }
.bk-menu__inner {
  min-height: 100%;
  max-width: var(--maxw); margin-inline: auto;
  padding: 0 var(--gutter) 32px;
  display: flex; flex-direction: column;
}
.bk-menu__head { display: flex; justify-content: space-between; align-items: center; height: var(--header-h); }
.bk-menu__close { display: inline-flex; gap: 10px; align-items: center; font-size: 12px; letter-spacing: .01em; padding: 8px 0; }
.bk-menu__close span { font-size: 22px; line-height: 1; }
.bk-menu__list { flex: 1; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); grid-template-rows: repeat(7, auto); grid-auto-flow: column; column-gap: var(--gutter); align-content: center; padding-block: 24px; }
.bk-menu__item { border-top: 1px solid rgba(242,239,233,.1); }
.bk-menu__link {
  display: grid; grid-template-columns: 44px 1fr auto; align-items: baseline; gap: 12px;
  padding: clamp(10px, 1.4vw, 18px) 0;
  text-decoration: none;
  transition: color .3s var(--ease), padding .4s var(--ease);
}
.bk-menu__num { font-size: 12px; letter-spacing: .1em; color: var(--wd-muted); font-variant-numeric: tabular-nums; }
.bk-menu__title { font-family: var(--font-display); font-size: clamp(1.5rem, 2.6vw, 2.6rem); line-height: 1.05; letter-spacing: -.02em; }
.bk-menu__pl { font-size: 12px; color: var(--wd-muted); letter-spacing: .01em; }
.bk-menu__link:hover, .bk-menu__link:focus-visible { color: var(--wd-accent-soft); padding-left: 10px; }
.bk-menu__link[aria-current="true"] .bk-menu__num { color: var(--wd-accent); }
.bk-menu__foot { padding-top: 16px; }
.bk-menu-open { overflow: hidden; }

/* ---------- Buttons ---------- */
.bk-btn {
  position: relative;
  display: inline-flex; align-items: center; justify-content: center; gap: 14px;
  min-height: 56px; padding: 0 30px;
  font-size: 13px; font-weight: 500; letter-spacing: .01em;
  text-decoration: none;
  border-radius: 999px;
  overflow: hidden;
  isolation: isolate;
  transition: color .45s var(--ease), border-color .45s var(--ease), transform .45s var(--ease);
}
.bk-btn::before {
  content: ""; position: absolute; inset: 0; z-index: -1;
  border-radius: inherit;
  transform: translateY(101%);
  transition: transform .55s var(--ease);
}
.bk-btn:hover::before, .bk-btn:focus-visible::before { transform: translateY(0); }
.bk-btn__arrow { display: inline-block; transition: transform .45s var(--ease); }
.bk-btn:hover .bk-btn__arrow { transform: translateX(5px); }
.bk-btn:hover .bk-btn__arrow--back { transform: translateX(-5px); }
.bk-btn:active { transform: scale(.98); }
.bk-btn--ghost { border: 1px solid rgba(242,239,233,.28); color: var(--wd-text); }
.bk-btn--ghost::before { background: var(--wd-text); }
.bk-btn--ghost:hover, .bk-btn--ghost:focus-visible { color: var(--wd-bg); border-color: var(--wd-text); }
.bk-btn--solid { background: var(--wd-accent); color: var(--wd-bg); }
.bk-btn--solid::before { background: var(--wd-accent-soft); }

.bk-media-btn {
  display: block; width: 100%;
  position: relative;
  cursor: zoom-in;
  overflow: hidden;
}
.bk-media-btn img { width: 100%; transition: transform 1.2s var(--ease), filter .6s var(--ease); }
.bk-media-btn::after {
  content: "+";
  position: absolute; right: 14px; bottom: 14px;
  width: 38px; height: 38px; border-radius: 50%;
  display: grid; place-items: center;
  font-size: 20px; font-weight: 300; line-height: 1;
  background: rgba(5,7,6,.55); color: var(--wd-text);
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
  opacity: 0; transform: scale(.8);
  transition: opacity .4s var(--ease), transform .4s var(--ease);
}
.bk-media-btn:hover img { transform: scale(1.025); }
.bk-media-btn:hover::after, .bk-media-btn:focus-visible::after { opacity: 1; transform: scale(1); }

/* ==========================================================================
   00 — HERO
   ========================================================================== */
.bk-hero {
  min-height: calc(100vh - var(--site-offset)); min-height: calc(100svh - var(--site-offset));
  padding-block: calc(var(--header-h) + 20px) clamp(24px, 3vw, 40px);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  grid-template-rows: auto 1fr auto;
  overflow: hidden;
}
.bk-hero__decor {
  position: absolute; z-index: 0;
  right: -12vw; top: 50%;
  width: min(78vw, 1100px);
  transform: translateY(-50%);
  color: var(--th-gold);
  opacity: .07;
  pointer-events: none;
}
.bk-hero__sign { width: 100%; height: auto; }
.bk-hero__top, .bk-hero__body, .bk-hero__bottom { position: relative; z-index: 1; }
.bk-hero__top { display: flex; justify-content: space-between; gap: 16px; padding-top: clamp(12px, 2vw, 28px); }
.bk-hero__body {
  align-self: end;
  position: relative;
  padding-bottom: clamp(32px, 5vw, 72px);
}
.bk-hero__title {
  font-family: var(--font-display);
  font-size: var(--fs-mega);
  line-height: .86;
  letter-spacing: -.055em;
  font-weight: 400;
  margin-left: -.05em;
}
.bk-hero__title .bk-line { display: block; overflow: hidden; padding: .16em 0 .06em; margin-top: -.16em; }
.bk-hero__title .bk-line__in { display: inline-block; }
.bk-hero__title .bk-line:nth-child(2) { padding-left: clamp(0px, 9vw, 180px); }
.bk-hero__dot { color: var(--th-gold); }
.bk-hero__aside {
  position: absolute; right: var(--gutter); bottom: calc(clamp(32px, 5vw, 72px) + 2.4vw);
  display: grid; gap: 22px; justify-items: start; width: min(30vw, 340px);
}
.bk-hero__logo { width: clamp(200px, 19vw, 320px); height: auto; color: var(--th-ivory); }
.bk-hero__sub { font-size: var(--fs-lead); font-weight: 300; letter-spacing: -.01em; color: var(--wd-muted); margin: 0; }
.bk-hero__bottom { display: flex; justify-content: space-between; align-items: end; gap: 16px; }
.bk-scroll-cue {
  display: inline-flex; align-items: center; gap: 14px;
  font-size: 12px; letter-spacing: .01em; text-decoration: none;
  color: var(--wd-text);
}
.bk-scroll-cue__track { position: relative; width: 1px; height: 44px; background: rgba(242,239,233,.2); overflow: hidden; }
.bk-scroll-cue__dot { position: absolute; left: 0; top: 0; width: 1px; height: 14px; background: var(--wd-accent); animation: bk-cue 2.2s var(--ease-in-out) infinite; }
@keyframes bk-cue { 0% { transform: translateY(-14px); } 100% { transform: translateY(44px); } }

/* ==========================================================================
   INTRO — opening book
   ========================================================================== */
.bk-book { display: none; }
.bk-preload .bk-book, .bk-book.bk-is-playing {
  display: block;
  position: fixed; inset: 0; z-index: 160;
}
.bk-book__stage {
  position: absolute; inset: 0;
  perspective: 2400px;
  perspective-origin: 0% 50%;
}
.bk-book__leaf {
  position: absolute; inset: 0;
  transform-origin: 0% 50%;
  transform-style: preserve-3d;
  will-change: transform;
}
.bk-book__face {
  position: absolute; inset: 0;
  backface-visibility: hidden; -webkit-backface-visibility: hidden;
  overflow: hidden;
}
.bk-book__face--back { transform: rotateY(180deg); }
.bk-book__leaf--cover .bk-book__face--front {
  background:
    radial-gradient(120% 90% at 60% 40%, rgba(255,255,255,.05), transparent 60%),
    var(--th-green);
}
.bk-book__leaf--cover .bk-book__face--back { background: #142f29; }
.bk-book__leaf--page .bk-book__face--front {
  background:
    linear-gradient(90deg, rgba(26,60,52,.12), transparent 7%),
    var(--th-ivory);
}
.bk-book__leaf--page .bk-book__face--back { background: #E6E1D6; }
.bk-book__shade {
  position: absolute; inset: 0; pointer-events: none;
  background: linear-gradient(90deg, rgba(0,0,0,.55), rgba(0,0,0,.15) 60%, rgba(0,0,0,0));
  opacity: 0;
}
.bk-book__spine {
  position: absolute; left: 0; top: 0; bottom: 0; width: clamp(14px, 2vw, 28px);
  background: linear-gradient(90deg, rgba(0,0,0,.45), rgba(0,0,0,0));
  pointer-events: none;
}

.bk-book__cover {
  position: absolute; inset: clamp(16px, 3vw, 40px);
  display: grid; grid-template-rows: 1fr auto auto; justify-items: center; align-items: center;
  padding: clamp(32px, 6vh, 72px) 24px clamp(24px, 4vh, 48px);
  border: 1px solid rgba(197,160,101,.45);
  outline: 1px solid rgba(197,160,101,.18); outline-offset: 6px;
  color: var(--th-gold);
  text-align: center;
}
.bk-book__logo { width: clamp(150px, 18vw, 260px); height: auto; align-self: center; }
.bk-book__label { margin: 0 0 10px; font-size: 12px; letter-spacing: .01em; color: var(--th-au4); }
.bk-book__foot { margin: 0; font-size: 11px; letter-spacing: .01em; color: rgba(220,198,162,.6); }

.bk-book__page {
  position: absolute; inset: 0;
  display: grid; place-content: center; justify-items: center; gap: 14px;
  padding: 24px; text-align: center;
  color: var(--th-green);
}
.bk-book__kicker { margin: 0; font-size: 11px; letter-spacing: .01em; color: var(--th-g3); }
.bk-book__title { margin: 0; font-family: var(--font-display); font-size: clamp(2.6rem, 7vw, 6.5rem); line-height: 1; letter-spacing: -.03em; padding-top: .3em; }
.bk-book__sub { margin: 0; font-size: clamp(1rem, 1.4vw, 1.25rem); font-weight: 300; color: var(--th-g2); }
.bk-book__words { margin: 18px 0 0; font-size: 11px; letter-spacing: .01em; color: #8a6a37; }

.bk-book__skip {
  position: absolute; right: var(--gutter); bottom: clamp(20px, 4vh, 40px); z-index: 2;
  min-height: 40px; padding: 0 18px; border-radius: 999px;
  font-size: 11px; letter-spacing: .01em; font-weight: 500;
  color: var(--th-ivory);
  box-shadow: inset 0 0 0 1px rgba(242,239,233,.3);
  transition: background-color .3s var(--ease), color .3s var(--ease);
}
.bk-book__skip:hover { background: var(--th-ivory); color: var(--th-green); }
@media (max-width: 767px) { .bk-book__skip { top: 28px; bottom: auto; right: 28px; } }
.bk-book-lock { overflow: hidden; }

/* preload state: hide hero pieces until GSAP takes over (removed by JS / timeout) */
.bk-preload .bk-hero__title .bk-line__in { transform: translateY(105%); }
.bk-preload [data-hero-fade], .bk-preload .bk-hero__logo { opacity: 0; }

/* ==========================================================================
   TEASER — looping film (its poster shares the page background, so it rises out of the dark)
   ========================================================================== */
.bk-teaser { position: relative; background: var(--bg); color: var(--fg); padding-block: clamp(72px, 9vw, 140px) clamp(48px, 6vw, 96px); }
.bk-teaser__head {
  display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
  gap: clamp(24px, 5vw, 96px); align-items: end;
  margin-bottom: clamp(28px, 4vw, 56px);
}
.bk-teaser__head .bk-eyebrow { margin-bottom: clamp(18px, 2vw, 28px); }
.bk-teaser__title { font-family: var(--font-display); font-size: var(--fs-display-md); line-height: 1; letter-spacing: -.03em; max-width: 12em; text-wrap: balance; }
.bk-teaser__lead { color: var(--muted); max-width: 30em; justify-self: end; margin: 0; padding-bottom: .4em; }
.bk-teaser__frame {
  position: relative;
  width: calc(100% - 2 * var(--gutter)); max-width: 1880px;
  margin: 0 auto;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: 6px;
  background: var(--wd-bg);
  box-shadow: 0 0 0 1px rgba(242,239,233,.08), 0 60px 120px -60px rgba(0,0,0,.9);
  transform-origin: 50% 0%;
}
.bk-teaser__video { display: block; width: 100%; height: 100%; object-fit: cover; background: var(--wd-bg); }
.bk-teaser__bar { position: absolute; left: 0; right: 0; bottom: 0; height: 2px; background: rgba(242,239,233,.08); pointer-events: none; }
.bk-teaser__bar-in { display: block; height: 100%; background: var(--th-gold); transform-origin: 0 50%; transform: scaleX(0); }
.bk-teaser__toggle {
  position: absolute; left: clamp(12px, 2vw, 28px); bottom: clamp(14px, 2vw, 28px);
  display: inline-flex; align-items: center; gap: 10px;
  min-height: 40px; padding: 0 16px 0 12px; border-radius: 999px;
  font-size: 11px; letter-spacing: .01em; font-weight: 500;
  color: var(--wd-text);
  background: rgba(5,7,6,.55);
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
  box-shadow: inset 0 0 0 1px rgba(242,239,233,.18);
  opacity: .0; transition: opacity .4s var(--ease), background-color .3s var(--ease), color .3s var(--ease);
}
.bk-teaser__frame:hover .bk-teaser__toggle, .bk-teaser__toggle:focus-visible, .bk-teaser__frame.bk-is-paused .bk-teaser__toggle { opacity: 1; }
.bk-teaser__toggle:hover { background: var(--wd-text); color: var(--wd-bg); }
.bk-teaser__icon { position: relative; width: 12px; height: 12px; }
.bk-teaser__icon::before, .bk-teaser__icon::after { content: ""; position: absolute; top: 0; width: 3px; height: 12px; background: currentColor; border-radius: 1px; }
.bk-teaser__icon::before { left: 2px; } .bk-teaser__icon::after { right: 2px; }
.bk-is-paused .bk-teaser__icon::before { left: 2px; width: 0; height: 0; background: none; border-style: solid; border-width: 6px 0 6px 10px; border-color: transparent transparent transparent currentColor; border-radius: 0; }
.bk-is-paused .bk-teaser__icon::after { display: none; }
.bk-teaser__meta { margin-top: 18px; }
@media (hover: none) { .bk-teaser__toggle { opacity: 1; } }
@media (max-width: 1023px) {
  .bk-teaser__head { grid-template-columns: minmax(0, 1fr); }
  .bk-teaser__lead { justify-self: start; }
}
@media (max-width: 767px) {
  .bk-teaser__frame { width: 100%; border-radius: 0; box-shadow: none; }
  .bk-teaser__toggle { width: 36px; min-height: 36px; padding: 0; justify-content: center; left: 10px; bottom: 10px; }
  .bk-teaser__toggle [data-teaser-label] { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
}

/* ==========================================================================
   01 — BEGINNING
   ========================================================================== */
.bk-beginning { padding-bottom: 0; }
.bk-beginning__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  gap: clamp(40px, 8vw, 160px);
  align-items: start;
}
.bk-beginning__lead p:not(.bk-lead) { color: var(--muted); max-width: 36em; }
.bk-beginning__lead .bk-lead { margin-bottom: 1.2em; }
.bk-pull { margin-top: clamp(32px, 4vw, 56px); padding-left: 24px; border-left: 1px solid var(--th-gold); }
.bk-pull p { font-family: var(--font-display); font-size: clamp(1.4rem, 2.2vw, 2.1rem); line-height: 1.15; letter-spacing: -.02em; margin-bottom: 14px; color: var(--fg); }
.bk-pull cite { font-style: normal; font-size: 12px; letter-spacing: .01em; color: var(--muted); }

.bk-facts { border-top: 1px solid var(--line); }
.bk-facts__row {
  display: grid; grid-template-columns: 120px 1fr; gap: 16px;
  padding: 16px 0; border-bottom: 1px solid var(--line);
}
.bk-facts dt { font-size: 12px; letter-spacing: .01em; color: var(--muted); padding-top: 3px; }
.bk-facts dd { font-size: 15px; line-height: 1.5; }

.bk-words { padding-block: clamp(96px, 12vw, 200px) var(--section-y); }
.bk-words__inner { position: relative; }
.bk-words__label { margin-bottom: clamp(24px, 3vw, 48px); }
.bk-words__list { display: grid; gap: clamp(4px, 1vw, 16px); }
.bk-word {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(220px, 300px);
  align-items: center;
  gap: clamp(24px, 4vw, 72px);
  border-top: 1px solid var(--line);
}
/* Gayathri metrics: ascent .73em / descent .49em, caps .05–.73em. With padding-top .44em
   the cap height sits optically centred between the rules for any line-height. */
.bk-word__text {
  font-family: var(--font-display);
  font-size: clamp(3rem, 8.2vw, 9.5rem);
  line-height: .9;
  padding-top: .44em;
  letter-spacing: -.02em;
  color: var(--fg);
  white-space: nowrap;
}
.bk-word__note { font-size: 15px; line-height: 1.55; color: var(--muted); display: grid; gap: 10px; }
.bk-word__idx { font-family: Georgia, "Times New Roman", serif; color: var(--th-gold); font-size: 17px; letter-spacing: .08em; }

/* ==========================================================================
   INTERLUDE
   ========================================================================== */
.bk-interlude {
  min-height: 100vh; min-height: 100svh;
  display: grid; align-items: end;
  overflow: hidden;
  isolation: isolate;
}
.bk-interlude__media { position: absolute; inset: 0; z-index: -2; overflow: hidden; }
.bk-interlude__media img { width: 100%; height: 115%; object-fit: cover; object-position: 50% 60%; will-change: transform; }
.bk-interlude__veil { position: absolute; inset: 0; z-index: -1; background: linear-gradient(180deg, rgba(5,7,6,.1) 30%, rgba(5,7,6,.78) 100%); }
.bk-interlude__content { padding-block: clamp(48px, 8vw, 120px); display: grid; gap: 28px; }
.bk-interlude__quote p {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4.6vw, 4.8rem);
  line-height: 1.02; letter-spacing: -.035em;
  max-width: 15em; margin-bottom: 18px;
  text-wrap: balance;
}
.bk-interlude__quote cite { font-style: normal; font-size: 12px; letter-spacing: .01em; color: var(--th-au4); }
.bk-interlude__credit { color: rgba(242,239,233,.6); }
/* light still life: the quote sits on the empty plaster wall on the left */
.bk-interlude--light { align-items: center; }
.bk-interlude--light .bk-interlude__veil { background: linear-gradient(90deg, rgba(242,239,233,.62) 0%, rgba(242,239,233,.28) 38%, rgba(242,239,233,0) 58%); }
.bk-interlude--light .bk-interlude__quote { max-width: min(46%, 660px); }
.bk-interlude--light .bk-interlude__quote p { color: var(--th-green); }
.bk-interlude--light .bk-interlude__quote cite { color: #7a5c2e; }
.bk-interlude--light .bk-interlude__credit { color: rgba(26,60,52,.6); }

/* ==========================================================================
   02 — CHALLENGE (sticky split)
   ========================================================================== */
.bk-challenge__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(40px, 8vw, 160px);
  align-items: start;
}
.bk-challenge__sticky { position: sticky; top: calc(var(--chrome-h) + 6vh); }
.bk-challenge__sticky .bk-display { margin-bottom: clamp(28px, 3vw, 48px); }
.bk-challenge__q { color: var(--fg); max-width: 22em; }
.bk-challenge__count { margin-top: clamp(32px, 4vw, 64px); color: var(--th-gold); font-variant-numeric: tabular-nums; }
.bk-challenge__list { display: grid; gap: clamp(20px, 2vw, 32px); padding-top: clamp(0px, 14vh, 160px); padding-bottom: 10vh; }
.bk-ccard {
  position: relative;
  padding: clamp(28px, 3.2vw, 52px);
  border: 1px solid var(--line);
  background: rgba(5,7,6,.14);
  transition: border-color .6s var(--ease), background-color .6s var(--ease);
}
.bk-ccard.bk-is-current { border-color: rgba(197,160,101,.55); background: rgba(5,7,6,.24); }
.bk-ccard__num { font-family: var(--font-display); color: var(--th-gold); font-size: 1.1rem; letter-spacing: .06em; display: block; margin-bottom: 26px; }
.bk-ccard__title { font-family: var(--font-display); font-size: clamp(1.6rem, 2.4vw, 2.4rem); line-height: 1.05; letter-spacing: -.025em; margin-bottom: 26px; }
.bk-ccard__label { font-size: 11px; letter-spacing: .01em; color: var(--th-au4); margin: 18px 0 6px; }
.bk-ccard p:not(.bk-ccard__label) { color: var(--th-g7); font-size: 15.5px; max-width: 34em; }

/* ==========================================================================
   03 — CONCEPT
   ========================================================================== */
.bk-ideas { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); column-gap: clamp(20px, 3vw, 48px); border-top: 1px solid var(--line); }
.bk-idea { padding-top: clamp(28px, 3vw, 48px); }
.bk-idea__photo {
  aspect-ratio: 4 / 5; overflow: hidden;
  margin: 0 0 clamp(24px, 3vw, 40px);
  background: #0b0f0d;
}
.bk-idea__photo img { width: 100%; height: 100%; object-fit: cover; }
.bk-idea__art {
  width: 84px; height: auto; aspect-ratio: 240 / 300;
  margin: 0 0 18px;
  fill: none; stroke: var(--th-gold); stroke-width: 1; stroke-linecap: round; stroke-linejoin: round;
  overflow: visible;
}
.bk-idea__art circle { fill: var(--th-gold); stroke: none; }
.bk-idea__num { font-family: Georgia, "Times New Roman", serif; color: var(--th-gold); font-size: 17px; letter-spacing: .08em; margin-bottom: clamp(22px, 2vw, 32px); }
.bk-idea__title { font-family: var(--font-display); font-size: clamp(2.4rem, 4.2vw, 4.4rem); line-height: .95; letter-spacing: -.015em; }
.bk-idea__sub { font-size: 12px; letter-spacing: .01em; color: var(--th-au4); margin: 14px 0 18px; }
.bk-idea__text { color: var(--muted); max-width: 26em; }

/* ==========================================================================
   04 — SYMBOL
   ========================================================================== */
.bk-symbol__layout {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
  gap: clamp(40px, 6vw, 120px);
  align-items: start;
}
.bk-symbol__stage {
  position: sticky; top: calc(var(--chrome-h) + 2vh);
  min-height: calc(100vh - var(--chrome-h) - 4vh);
  display: grid; grid-template-rows: 1fr auto auto; justify-items: center; align-items: center; gap: 22px;
  padding-block: 2vh;
}
.bk-symbol__figure {
  position: relative;
  width: min(100%, 62vh, 560px);
  aspect-ratio: 376 / 383;
  margin: 8% 0;
}
.bk-symbol__svg { width: 100%; height: 100%; color: var(--th-green); overflow: visible; }
.bk-symbol__svg g { transition: opacity .7s var(--ease), fill .7s var(--ease); }
.bk-symbol__overlay {
  position: absolute; inset: 0; width: 100%; height: 100%;
  overflow: visible; pointer-events: none;
  fill: none; stroke: var(--tint); stroke-width: 1.4; stroke-linecap: round;
}
.bk-symbol__overlay circle[r="5"] { fill: var(--th-ivory); stroke: var(--tint); stroke-width: 2; }
.bk-ov { opacity: 0; transition: opacity .6s var(--ease); }
.bk-ov [pathLength] { stroke-dasharray: 1; stroke-dashoffset: 1; transition: stroke-dashoffset 1.1s var(--ease); }
.bk-ov--circle circle { stroke-dasharray: .006 .012; stroke-dashoffset: 0; }
.bk-ov--stem path { stroke-dasharray: 1; }

/* dim non-active parts */
:where(.bk) [data-active="circle"] .bk-sg-leaf, :where(.bk) [data-active="circle"] .bk-sg-bud { opacity: .13; }
:where(.bk) [data-active="stem"] .bk-sg-ring, :where(.bk) [data-active="stem"] .bk-sg-leaf--l, :where(.bk) [data-active="stem"] .bk-sg-leaf--r { opacity: .13; }
:where(.bk) [data-active="leaves"] .bk-sg-ring, :where(.bk) [data-active="leaves"] .bk-sg-bud { opacity: .13; }
:where(.bk) [data-active="circle"] .bk-ov--circle, :where(.bk) [data-active="stem"] .bk-ov--stem, :where(.bk) [data-active="leaves"] .bk-ov--leaves, :where(.bk) [data-active="open"] .bk-ov--open { opacity: 1; }
:where(.bk) [data-active="circle"] .bk-ov--circle [pathLength], :where(.bk) [data-active="stem"] .bk-ov--stem [pathLength], :where(.bk) [data-active="leaves"] .bk-ov--leaves [pathLength], :where(.bk) [data-active="open"] .bk-ov--open [pathLength] { stroke-dashoffset: 0; }
:where(.bk) [data-active="circle"] .bk-ov--circle circle { stroke-dasharray: .006 .012; }
:where(.bk) [data-active="stem"] .bk-sg-leaf--m { opacity: .35; }
:where(.bk) [data-active="open"] .bk-sg-ring { fill: var(--th-gold); }

.bk-symbol__caption { color: var(--tint); min-height: 1.5em; }
.bk-symbol__tabs { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; }
.bk-symbol__tabs button {
  min-height: 40px; padding: 0 16px;
  border: 1px solid var(--line); border-radius: 999px;
  font-size: 12px; letter-spacing: .01em; font-weight: 500;
  color: var(--muted);
  transition: background-color .4s var(--ease), color .4s var(--ease), border-color .4s var(--ease);
}
.bk-symbol__tabs button:hover { border-color: var(--th-green); color: var(--th-green); }
.bk-symbol__tabs button[aria-selected="true"] { background: var(--th-green); border-color: var(--th-green); color: var(--th-ivory); }

.bk-symbol__steps { padding-block: 10vh 30vh; }
.bk-sstep {
  min-height: 72vh;
  display: flex; flex-direction: column; justify-content: center;
  max-width: 30em;
  opacity: .28;
  transition: opacity .6s var(--ease);
}
.bk-sstep.bk-is-active { opacity: 1; }
.bk-sstep__num { font-family: var(--font-display); color: var(--tint); font-size: 18px; margin-bottom: 18px; }
.bk-sstep__title { font-family: var(--font-display); font-size: clamp(2.4rem, 4.4vw, 4.6rem); line-height: .95; letter-spacing: -.015em; }
.bk-sstep__sub { font-size: 12px; letter-spacing: .01em; color: var(--tint); margin: 18px 0 22px; }
.bk-sstep p:last-child { color: var(--muted); font-size: 16.5px; }

/* ==========================================================================
   05 — CONSTRUCTION
   ========================================================================== */
.bk-construct { padding-block: 0; }
.bk-construct__pin { min-height: 100vh; min-height: 100svh; display: grid; align-items: center; padding-block: calc(var(--chrome-h) + 4vh) 6vh; }
.bk-construct__grid {
  display: grid;
  grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr);
  gap: clamp(40px, 6vw, 120px);
  align-items: center;
}
.bk-construct__text .bk-display { font-size: clamp(2.2rem, 4.2vw, 4.5rem); margin-bottom: clamp(24px, 3vw, 40px); }
.bk-construct__text p:not(.bk-lead):not(.bk-eyebrow) { color: var(--muted); max-width: 32em; }
.bk-phases { margin-top: clamp(28px, 4vw, 56px); border-top: 1px solid var(--line); }
.bk-phase {
  display: flex; align-items: center; gap: 18px;
  padding: 12px 0; border-bottom: 1px solid var(--line);
  font-size: 14px; color: var(--muted);
  transition: color .5s var(--ease);
}
.bk-phase span { font-size: 11px; letter-spacing: .12em; color: var(--muted); font-variant-numeric: tabular-nums; transition: color .5s var(--ease); }
.bk-phase.bk-is-on { color: var(--fg); }
.bk-phase.bk-is-on span { color: var(--th-gold); }

.bk-construct__stage { position: relative; display: grid; justify-items: center; gap: clamp(20px, 3vh, 36px); }
.bk-construct__figure { width: min(100%, 62vh, 640px); aspect-ratio: 630 / 650; }
.bk-construction { width: 100%; height: 100%; overflow: hidden; }
.bk-cx-lines path { stroke: rgba(242,239,233,.22); stroke-width: 1; fill: none; }
.bk-cx-circles path { stroke: var(--th-gold); stroke-width: 1.1; fill: none; opacity: .75; }
.bk-cx-nodes path { fill: var(--wd-bg); stroke: rgba(197,160,101,.85); stroke-width: 1.4; transform-box: fill-box; transform-origin: center; transform: scale(.5); }
.bk-cx-symbol path { fill: var(--th-ivory); stroke: none; }
.bk-construct__final { width: min(70%, 380px); }
.bk-construct__logo { width: 100%; height: auto; color: var(--th-gold); }
.bk-construct__src { text-align: center; }

/* ==========================================================================
   06 — TYPOGRAPHY
   ========================================================================== */
.bk-wordmark { margin-bottom: clamp(80px, 10vw, 160px); }
.bk-wordmark__art { overflow: hidden; }
.bk-wordmark__svg { width: 100%; height: auto; color: var(--th-green); overflow: visible; }
.bk-wm-marks { fill: none; stroke: var(--tint); }
.bk-wm-mark path { stroke-width: 1.4; }
.bk-wm-mark circle { fill: var(--th-ivory); stroke-width: 1.4; }
.bk-wm-mark text { fill: var(--tint); stroke: none; font-family: var(--font-text); font-size: 11px; font-weight: 600; text-anchor: middle; }
.bk-wordmark__notes {
  display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px;
  margin: clamp(28px, 3vw, 44px) 0 16px; padding-top: 20px; border-top: 1px solid var(--line);
}
.bk-wordmark__notes li { display: flex; gap: 12px; align-items: baseline; font-size: 15px; color: var(--muted); }
.bk-wordmark__notes span {
  flex: none; width: 22px; height: 22px; border-radius: 50%;
  display: grid; place-items: center;
  border: 1px solid var(--tint); color: var(--tint);
  font-size: 11px; font-weight: 600; transform: translateY(-1px);
}

.bk-specimens { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: clamp(24px, 4vw, 72px); margin-bottom: clamp(80px, 10vw, 160px); }
.bk-spec { padding-top: 4px; }
.bk-spec__head { display: flex; align-items: center; gap: 18px; margin-bottom: clamp(16px, 2vw, 32px); }
.bk-spec__head .bk-meta { color: var(--fg); }
.bk-spec__rule { flex: 1; height: 1px; background: var(--line); }
.bk-spec__aa { font-size: clamp(7rem, 17vw, 17rem); line-height: .9; letter-spacing: -.05em; margin-bottom: .1em; color: var(--th-green); }
.bk-spec--gayathri .bk-spec__aa { font-family: var(--font-display); padding-top: .22em; margin-bottom: -.23em; } /* optical alignment with Inter's metrics */
.bk-spec--inter .bk-spec__aa { font-family: var(--font-text); font-weight: 300; letter-spacing: -.07em; }
.bk-mask { display: inline-block; overflow: hidden; padding: .26em .04em .1em 0; margin-top: -.26em; }
.bk-mask > span { display: inline-block; }
.bk-spec__name { font-size: clamp(1.6rem, 2.4vw, 2.4rem); line-height: 1.1; letter-spacing: -.02em; margin-bottom: 20px; }
.bk-spec--gayathri .bk-spec__name, .bk-spec--gayathri .bk-spec__set, .bk-spec--gayathri .bk-spec__digits, .bk-spec--gayathri .bk-spec__weights { font-family: var(--font-display); }
.bk-spec__set { font-size: clamp(1.05rem, 1.5vw, 1.4rem); line-height: 1.55; color: var(--muted); letter-spacing: .01em; }
.bk-spec__digits { font-size: clamp(1.4rem, 2.2vw, 2rem); letter-spacing: .04em; margin-top: 12px; }
.bk-spec__weights { display: flex; flex-wrap: wrap; gap: 8px 28px; margin-top: 24px; padding-top: 18px; border-top: 1px solid var(--line); font-size: 1.15rem; }

.bk-type-use {
  display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, .8fr);
  gap: clamp(40px, 6vw, 120px); align-items: center;
}
.bk-type-use__sample { padding: clamp(32px, 5vw, 80px); background: var(--card); }
.bk-type-use__h { font-family: var(--font-display); font-size: clamp(2.4rem, 5vw, 5rem); line-height: 1; letter-spacing: -.035em; margin: 26px 0 24px; color: var(--th-green); }
.bk-type-use__p { font-size: 17px; line-height: 1.65; color: var(--th-g2); max-width: 32em; }
.bk-type-use__specs { display: flex; gap: 40px; margin-top: 32px; padding-top: 20px; border-top: 1px solid var(--line); }
.bk-type-use__specs dt { font-size: 11px; letter-spacing: .01em; color: var(--muted); }
.bk-type-use__specs dd { font-size: 15px; font-weight: 500; }
.bk-type-use__media { justify-self: center; width: min(100%, 340px); }
.bk-type-use__media .bk-media-btn { border-radius: 28px; box-shadow: 0 40px 80px -40px rgba(26,60,52,.45), 0 0 0 1px rgba(26,60,52,.08); }
.bk-type-use__media figcaption { margin-top: 16px; text-align: center; }

/* ==========================================================================
   07 — COLOR SYSTEM
   ========================================================================== */
.bk-colors { padding-bottom: 0; }
.bk-colors__intro { padding-bottom: clamp(48px, 6vw, 96px); }
.bk-colors__intro .bk-display { margin-bottom: clamp(24px, 3vw, 40px); max-width: 12em; }
.bk-colors__stage {
  --c-bg: #1A3C34;
  --c-ink: #F2EFE9;
  position: relative;
  color: var(--c-ink);
}
.bk-colors__bg {
  position: sticky; top: 0;
  height: 100vh; height: 100svh;
  margin-bottom: -100vh; margin-bottom: -100svh;
  background: var(--c-bg);
}
.bk-no-gsap .bk-colors__bg { transition: background-color .9s var(--ease); }
.bk-no-gsap .bk-colors__stage { transition: color .9s var(--ease); }
.bk-cpanel { position: relative; min-height: 100vh; min-height: 100svh; display: grid; align-items: center; }
.bk-cpanel__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, .7fr);
  grid-template-areas: "role role" "name meta";
  gap: clamp(20px, 3vw, 48px) clamp(32px, 6vw, 120px);
  align-items: end;
  padding-block: calc(var(--chrome-h) + 4vh) 8vh;
}
.bk-cpanel__role { grid-area: role; color: inherit; opacity: .75; display: flex; gap: 16px; margin-bottom: clamp(12px, 2vw, 32px); }
.bk-cpanel__role span { font-variant-numeric: tabular-nums; }
.bk-cpanel__name {
  grid-area: name;
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 6.8vw, 7.8rem);
  line-height: .92; letter-spacing: -.05em;
}
.bk-cpanel__meta { grid-area: meta; display: grid; gap: 22px; padding-bottom: 1vw; }
.bk-cpanel__meta p { font-size: 16px; line-height: 1.6; opacity: .82; max-width: 22em; margin: 0; }
.bk-hex-btn {
  justify-self: start;
  display: inline-flex; align-items: baseline; gap: 14px;
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 4vw, 3.8rem);
  line-height: 1; letter-spacing: -.02em;
  padding-bottom: 10px;
  border-bottom: 1px solid currentColor;
  cursor: copy;
  transition: opacity .3s var(--ease);
}
.bk-hex-btn__hint { font-family: var(--font-text); font-size: 11px; letter-spacing: .01em; opacity: .7; transition: opacity .3s var(--ease), transform .3s var(--ease); }
.bk-hex-btn:hover .bk-hex-btn__hint { opacity: 1; transform: translateX(4px); }
.bk-cpanel__values { display: flex; gap: 32px; }
.bk-cpanel__values dt { font-size: 11px; letter-spacing: .01em; opacity: .65; }
.bk-cpanel__values dd { font-size: 15px; font-variant-numeric: tabular-nums; }

/* own stacking layer: the sticky colour field (negative margin) may extend past the stage */
.bk-palette { position: relative; z-index: 1; background: var(--bg); padding-block: var(--section-y); }
.bk-palette__grid { display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(0, .75fr); gap: clamp(40px, 6vw, 112px); align-items: start; }
.bk-palette__head { margin-bottom: clamp(32px, 4vw, 56px); }
.bk-palette__head .bk-eyebrow { color: var(--fg); }
.bk-palette__intro { color: var(--muted); max-width: 34em; }
.bk-scale { margin-bottom: clamp(28px, 3vw, 44px); }
.bk-scale__label { margin-bottom: 14px; }
.bk-scale__list { display: grid; grid-template-columns: repeat(7, minmax(0, 1fr)); gap: 0; }
.bk-scale--single .bk-scale__list { grid-template-columns: minmax(0, 1fr); max-width: calc(100% / 7 * 2); }
.bk-sw {
  position: relative;
  display: flex; flex-direction: column; justify-content: flex-end;
  width: 100%; height: clamp(120px, 14vw, 220px);
  padding: 12px;
  background: var(--sw);
  text-align: left;
  overflow: hidden;
  transition: transform .5s var(--ease), box-shadow .5s var(--ease);
  box-shadow: inset 0 0 0 1px rgba(26,60,52,.06);
}
.bk-sw:hover, .bk-sw:focus-visible { transform: translateY(-8px); z-index: 2; box-shadow: 0 24px 40px -24px rgba(26,60,52,.5); }
.bk-sw.bk-is-selected::before { content: ""; position: absolute; top: 12px; left: 12px; width: 8px; height: 8px; border-radius: 50%; background: currentColor; }
.bk-sw__name, .bk-sw__hex { display: block; font-size: 11px; line-height: 1.35; letter-spacing: .04em; transition: opacity .4s var(--ease), transform .4s var(--ease); }
.bk-sw__name { font-weight: 600; opacity: 0; transform: translateY(8px); }
.bk-sw__hex { font-variant-numeric: tabular-nums; opacity: .85; }
.bk-sw:hover .bk-sw__name, .bk-sw:focus-visible .bk-sw__name, .bk-sw.bk-is-selected .bk-sw__name { opacity: 1; transform: none; }
.bk-sw[data-ink="light"] { color: var(--th-ivory); }
.bk-sw[data-ink="dark"] { color: var(--th-green); }

.bk-preview { position: sticky; top: calc(var(--chrome-h) + 24px); }
.bk-preview__canvas {
  --pv-bg: #1A3C34; --pv-ink: #C5A065;
  aspect-ratio: 4 / 5;
  display: grid; place-items: center;
  background: var(--pv-bg);
  transition: background-color .7s var(--ease);
  box-shadow: inset 0 0 0 1px rgba(26,60,52,.08);
}
.bk-preview__logo { width: 62%; height: auto; color: var(--pv-ink); transition: color .7s var(--ease); }
.bk-preview__info { padding-top: 18px; display: grid; gap: 4px; }
.bk-preview__name { font-family: var(--font-display); font-size: 1.6rem; line-height: 1.1; margin: 0; }
.bk-preview__row { display: flex; justify-content: space-between; gap: 16px; font-size: 13px; color: var(--muted); font-variant-numeric: tabular-nums; margin: 0; }

/* ==========================================================================
   08 — LOGO SYSTEM
   ========================================================================== */
.bk-lsys__app { display: grid; grid-template-columns: minmax(0, 1fr); gap: 0; border: 1px solid var(--line); }
.bk-lsys__controls {
  display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 16px;
  padding: 16px; border-bottom: 1px solid var(--line);
}
.bk-tabs { display: flex; flex-wrap: wrap; gap: 4px; }
.bk-tabs button, .bk-seg button {
  min-height: 42px; padding: 0 18px;
  border-radius: 999px;
  font-size: 12px; font-weight: 500; letter-spacing: .01em;
  color: var(--muted);
  transition: background-color .4s var(--ease), color .4s var(--ease);
}
.bk-tabs button:hover, .bk-seg button:hover { color: var(--fg); }
.bk-tabs button[aria-selected="true"] { background: var(--th-ivory); color: var(--th-green); }
.bk-lsys__toggles { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; }
.bk-seg { display: flex; gap: 2px; padding: 3px; border: 1px solid var(--line); border-radius: 999px; }
.bk-seg button { display: inline-flex; align-items: center; gap: 8px; min-height: 36px; padding: 0 14px; }
.bk-seg button[aria-checked="true"] { background: var(--wd-surface-2); color: var(--fg); }
.bk-seg__dot { width: 10px; height: 10px; border-radius: 50%; background: var(--dot); box-shadow: 0 0 0 1px rgba(242,239,233,.35); }
.bk-switch { display: inline-flex; align-items: center; gap: 10px; min-height: 42px; padding: 0 8px; font-size: 12px; letter-spacing: .01em; font-weight: 500; color: var(--muted); }
.bk-switch__track { position: relative; width: 38px; height: 22px; border-radius: 999px; border: 1px solid rgba(242,239,233,.3); transition: background-color .4s var(--ease), border-color .4s var(--ease); }
.bk-switch__thumb { position: absolute; top: 3px; left: 3px; width: 14px; height: 14px; border-radius: 50%; background: var(--wd-text); transition: transform .4s var(--ease); }
.bk-switch[aria-checked="true"] { color: var(--fg); }
.bk-switch[aria-checked="true"] .bk-switch__track { background: var(--wd-accent); border-color: var(--wd-accent); }
.bk-switch[aria-checked="true"] .bk-switch__thumb { transform: translateX(16px); background: var(--wd-bg); }

.bk-lsys__stage {
  --stage-bg: var(--th-ivory); --stage-ink: var(--th-green); --cs: rgba(26,60,52,.5); --cs-fill: rgba(26,60,52,.06);
  position: relative;
  min-height: clamp(360px, 46vw, 640px);
  display: grid; place-items: center;
  padding: clamp(48px, 6vw, 96px) 24px;
  background: var(--stage-bg);
  color: var(--stage-ink);
  transition: background-color .7s var(--ease), color .7s var(--ease);
  overflow: hidden;
}
:where(.bk) [data-bg="dark"] .bk-lsys__stage { --stage-bg: var(--wd-bg); --stage-ink: var(--th-ivory); --cs: rgba(242,239,233,.45); --cs-fill: rgba(242,239,233,.05); }
:where(.bk) [data-bg="green"] .bk-lsys__stage { --stage-bg: var(--th-green); --stage-ink: var(--th-gold); --cs: rgba(197,160,101,.6); --cs-fill: rgba(197,160,101,.07); }
.bk-lsys__logo { position: relative; grid-area: 1 / 1; --m: 20px; }
.bk-lsys__logo[hidden] { display: none; }
.bk-lsys__logo[data-logo="primary"] { width: min(62vw, 720px); }
.bk-lsys__logo[data-logo="alt-h"] { width: min(52vw, 520px); }
.bk-lsys__logo[data-logo="alt-v"] { width: min(34vw, 300px); }
.bk-lsys__svg { width: 100%; height: auto; position: relative; z-index: 1; }
.bk-lsys__logo.bk-is-entering .bk-lsys__svg { animation: bk-logoIn .8s var(--ease) both; }
@keyframes bk-logoIn { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: none; } }

.bk-cs { position: absolute; inset: calc(var(--m) * -2); border: 1px dashed var(--cs); opacity: 0; transition: opacity .5s var(--ease); pointer-events: none; }
.bk-cs__box { position: absolute; inset: calc(var(--m) * 2); background: var(--cs-fill); outline: 1px solid var(--cs); }
.bk-cs__m { position: absolute; width: var(--m); height: calc(var(--m) * 2); }
.bk-cs__m::before, .bk-cs__m::after { content: ""; position: absolute; left: 0; width: var(--m); height: var(--m); border-radius: 50%; border: 1px solid var(--cs); box-sizing: border-box; }
.bk-cs__m::before { top: 0; } .bk-cs__m::after { top: var(--m); }
.bk-cs__m--t { top: 0; left: calc(50% - var(--m) / 2); }
.bk-cs__m--b { bottom: 0; left: calc(50% - var(--m) / 2); }
.bk-cs__m--l, .bk-cs__m--r { top: calc(50% - var(--m) / 2); height: var(--m); width: calc(var(--m) * 2); }
.bk-cs__m--l { left: 0; } .bk-cs__m--r { right: 0; }
.bk-cs__m--l::before, .bk-cs__m--r::before { top: 0; left: 0; }
.bk-cs__m--l::after, .bk-cs__m--r::after { top: 0; left: var(--m); }
.bk-show-cs .bk-cs { opacity: 1; }
.bk-lsys__stage-meta { position: absolute; left: 20px; bottom: 16px; color: var(--stage-ink); opacity: .6; }

.bk-lsys__info { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr); border-top: 1px solid var(--line); }
.bk-lsys__usage, .bk-lsys__clear { padding: clamp(24px, 3vw, 44px); }
.bk-lsys__clear { border-left: 1px solid var(--line); }
.bk-lsys__usage .bk-meta, .bk-lsys__clear .bk-meta { margin-bottom: 14px; }
.bk-lsys__vname { font-family: var(--font-display); font-size: clamp(1.6rem, 2.4vw, 2.4rem); line-height: 1.05; letter-spacing: -.02em; margin-bottom: 14px; }
.bk-lsys__usage p:not(.bk-meta), .bk-lsys__clear p:not(.bk-meta) { color: var(--muted); max-width: 40em; }
.bk-lsys__module { display: flex; gap: 12px; align-items: baseline; margin-top: 14px; font-size: 14px; }
.bk-lsys__module-dot { flex: none; width: 12px; height: 12px; border-radius: 50%; border: 1px solid var(--th-gold); transform: translateY(1px); }

.bk-avatars { margin-top: clamp(56px, 7vw, 112px); display: grid; grid-template-columns: auto auto minmax(0, 1fr); gap: 24px clamp(24px, 4vw, 64px); align-items: center; }
.bk-avatars__list { display: flex; gap: clamp(12px, 1.6vw, 24px); }
.bk-avatar { width: clamp(72px, 8vw, 120px); aspect-ratio: 1; border-radius: 22%; display: grid; place-items: center; box-shadow: inset 0 0 0 1px rgba(242,239,233,.08); }
.bk-avatar svg { width: 58%; height: auto; }
.bk-avatar--green { background: var(--th-green); color: var(--th-gold); }
.bk-avatar--gold { background: var(--th-au4); color: var(--th-green); }
.bk-avatar--ivory { background: var(--th-ivory); color: var(--th-green); }
.bk-avatars__text { color: var(--muted); max-width: 30em; font-size: 15px; margin: 0; }

/* ==========================================================================
   09 — DIGITAL
   ========================================================================== */
.bk-digital .bk-chapter__head { margin-bottom: clamp(48px, 6vw, 96px); }
.bk-hero-shot { margin: 0 auto clamp(96px, 12vw, 200px); width: min(100%, calc(100% - 2 * var(--gutter) + 8vw)); max-width: 1880px; }
.bk-hero-shot__btn { overflow: hidden; }
.bk-hero-shot img { width: 100%; height: auto; transform-origin: 50% 50%; }
.bk-hero-shot figcaption { margin-top: 18px; }
.bk-hero-shot--after { margin: clamp(96px, 12vw, 200px) auto 0; }

.bk-digital__kb {
  display: grid; grid-template-columns: minmax(0, .7fr) minmax(0, 1.3fr);
  gap: clamp(40px, 6vw, 120px); align-items: center;
  margin-bottom: clamp(96px, 12vw, 200px);
}
.bk-digital__kb-text p:not(.bk-eyebrow):not(.bk-meta) { color: var(--muted); }
.bk-digital__hint { margin-top: 28px; color: var(--th-gold); }
.bk-browser { border-radius: 12px; overflow: hidden; background: #fbfaf7; box-shadow: 0 60px 120px -60px rgba(0,0,0,.9), 0 0 0 1px rgba(242,239,233,.08); }
.bk-browser__bar { display: flex; align-items: center; gap: 16px; height: 40px; padding: 0 14px; background: #ECE8E0; color: #5A726B; }
.bk-browser__dots { display: flex; gap: 6px; }
.bk-browser__dots i { width: 9px; height: 9px; border-radius: 50%; background: #CFC9BE; }
.bk-browser__url { flex: 1; max-width: 360px; margin-inline: auto; height: 24px; display: grid; place-items: center; background: #F7F5F0; border-radius: 6px; font-size: 11.5px; letter-spacing: .02em; color: #5A726B; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; padding-inline: 10px; }
.bk-browser__view { position: relative; aspect-ratio: 16 / 10; overflow: hidden; }
.bk-browser__page { width: 100%; height: auto; will-change: transform; }
.bk-browser figcaption { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }

.bk-devices {
  display: grid; grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2vw, 32px); align-items: start;
}
.bk-device .bk-media-btn { border-radius: clamp(18px, 2.4vw, 34px); box-shadow: 0 50px 90px -50px rgba(0,0,0,.95), 0 0 0 1px rgba(242,239,233,.1); }
.bk-device figcaption { margin-top: 16px; }
.bk-device--a { grid-column: 1 / span 3; margin-top: 10vh; }
.bk-device--b { grid-column: 4 / span 3; }
.bk-device--social { grid-column: 8 / span 5; align-self: center; }
.bk-device--social .bk-media-btn { border-radius: 4px; }
.bk-device--social figcaption { display: grid; gap: 10px; margin-top: 22px; }
.bk-device__text { color: var(--muted); font-size: 15px; max-width: 30em; }

/* ==========================================================================
   10 — PHYSICAL
   ========================================================================== */
.bk-gallery {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  column-gap: clamp(16px, 2vw, 32px);
  row-gap: clamp(56px, 7vw, 120px);
  align-items: start;
}
.bk-gitem figcaption { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 14px; margin-top: 16px; font-size: 15px; font-weight: 500; }
.bk-gitem__idx { font-size: 11px; letter-spacing: .12em; color: var(--tint); font-variant-numeric: tabular-nums; }
.bk-gitem__note { flex-basis: 100%; padding-left: 0; font-size: 13px; font-weight: 400; color: var(--muted); }
.bk-gitem__frame { display: block; overflow: hidden; }
.bk-gitem__frame img { width: 100%; height: 100%; object-fit: cover; }
.bk-gitem .bk-media-btn { background: var(--card); }

.bk-gitem--bag { grid-column: 1 / span 8; }
.bk-gitem--bag .bk-gitem__frame { aspect-ratio: 16 / 10.5; }
.bk-gitem--cards { grid-column: 10 / span 3; margin-top: 18vh; }
.bk-gitem--cards .bk-gitem__frame { aspect-ratio: 4 / 5; }
.bk-gitem--caps { grid-column: 2 / span 5; }
.bk-gitem--caps .bk-gitem__frame { aspect-ratio: 4 / 3; }
.bk-gitem--caps .bk-gitem__frame img { object-position: 55% 50%; }
.bk-gitem--sign { grid-column: 8 / span 5; margin-top: 14vh; }
.bk-gitem--sign .bk-gitem__frame { aspect-ratio: 4 / 3; }
.bk-gitem--sign .bk-gitem__frame img { object-position: 58% 50%; }
.bk-gitem--doy { grid-column: 1 / span 4; margin-top: 6vh; }
.bk-gitem--doy .bk-gitem__frame { aspect-ratio: 4 / 5; }
.bk-gitem--doy .bk-gitem__frame img { object-position: 50% 45%; }
.bk-gitem--folder { grid-column: 5 / span 4; margin-top: 20vh; }
.bk-gitem--folder .bk-gitem__frame { aspect-ratio: 1 / 1; }
.bk-gitem--dropper { grid-column: 10 / span 3; }
.bk-gitem--dropper .bk-gitem__frame { aspect-ratio: 3 / 5; }
.bk-gitem--dropper .bk-gitem__frame img { object-position: 50% 55%; }
.bk-gitem--tote { grid-column: 3 / span 6; }
.bk-gitem--tote .bk-gitem__frame { aspect-ratio: 16 / 9; }


/* ==========================================================================
   11 — DETAILS
   ========================================================================== */
.bk-principles { border-top: 1px solid var(--line); margin-bottom: clamp(72px, 9vw, 160px); }
.bk-principle {
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 22em);
  align-items: center; gap: 24px;
  padding: clamp(14px, 1.6vw, 26px) 0;
  border-bottom: 1px solid var(--line);
}
.bk-principle__word { font-family: var(--font-display); font-size: clamp(2.6rem, 7vw, 8rem); line-height: 1; letter-spacing: -.015em; padding-top: .12em; }
.bk-principle__text { color: var(--muted); font-size: 15.5px; }


/* ==========================================================================
   12 — COMPLETE
   ========================================================================== */
.bk-complete { min-height: 100vh; min-height: 100svh; display: grid; align-items: center; overflow: hidden; padding-block: clamp(96px, 9vw, 150px); }
.bk-complete__inner { position: relative; z-index: 1; display: grid; justify-items: center; text-align: center; }
.bk-section-bg { position: absolute; inset: 0; z-index: 0; overflow: hidden; pointer-events: none; }
.bk-section-bg img { width: 100%; height: 100%; object-fit: cover; }
.bk-section-bg::after { content: ""; position: absolute; inset: 0; }
.bk-section-bg--complete::after { background: radial-gradient(60% 55% at 50% 50%, rgba(26,60,52,.55), rgba(26,60,52,0) 70%), linear-gradient(180deg, var(--th-green) 0%, rgba(26,60,52,0) 14%, rgba(26,60,52,0) 86%, var(--th-green) 100%); }
.bk-section-bg--final img { object-position: 100% 60%; }
.bk-section-bg--final::after { background: linear-gradient(90deg, rgba(5,7,6,.92) 0%, rgba(5,7,6,.55) 50%, rgba(5,7,6,.1) 100%), linear-gradient(180deg, var(--wd-bg) 0%, rgba(5,7,6,0) 16%); }
.bk-complete__eyebrow { justify-content: center; }
.bk-complete__logo { width: clamp(170px, 17vw, 270px); margin: clamp(8px, 1.6vw, 24px) 0 clamp(32px, 4vw, 64px); color: var(--th-gold); }
.bk-complete__svg { width: 100%; height: auto; overflow: visible; }
.bk-complete__title { margin-bottom: clamp(24px, 3vw, 40px); }
.bk-complete__quote { font-size: clamp(1.15rem, 1.8vw, 1.6rem); font-weight: 300; line-height: 1.5; max-width: 30em; color: var(--th-g7); text-wrap: balance; }
.bk-values { display: flex; flex-wrap: wrap; justify-content: center; margin-top: clamp(40px, 5vw, 72px); border-top: 1px solid var(--line); }
.bk-values li {
  padding: 20px clamp(20px, 3.4vw, 56px) 0;
  font-size: 12px; letter-spacing: .01em; font-weight: 500;
  color: var(--th-gold);
}
.bk-values li + li { border-left: 1px solid var(--line); }

/* ==========================================================================
   13 — FINAL
   ========================================================================== */
.bk-final { min-height: 100vh; min-height: 100svh; display: grid; grid-template-rows: 1fr auto; padding-bottom: 0; }
.bk-final__inner { position: relative; z-index: 1; align-self: center; padding-block: 6vh; }
.bk-final__title { font-size: clamp(2.6rem, 6vw, 6.8rem); line-height: .92; letter-spacing: -.05em; max-width: 9em; margin-bottom: clamp(28px, 3vw, 48px); }
.bk-final__sub { font-family: var(--font-display); font-size: clamp(1.5rem, 2.4vw, 2.3rem); line-height: 1.2; color: var(--th-gold); margin-bottom: 10px; }
.bk-final__sig { margin-bottom: clamp(40px, 5vw, 72px); }
.bk-final__actions { display: flex; flex-wrap: wrap; gap: 14px; }
.bk-footer { position: relative; z-index: 1; display: flex; justify-content: space-between; align-items: center; gap: 16px; padding-block: 28px; border-top: 1px solid var(--line); }
.bk-footer__top { display: inline-flex; gap: 8px; align-items: center; color: var(--wd-text); transition: color .3s var(--ease); }
.bk-footer__top:hover { color: var(--wd-accent-soft); }


/* ---------- Toast ---------- */
.bk-toast {
  position: fixed; left: 50%; bottom: 28px; z-index: 140;
  display: inline-flex; align-items: center; gap: 12px;
  padding: 12px 20px 12px 14px;
  background: var(--wd-surface-2); color: var(--wd-text);
  border-radius: 999px;
  box-shadow: 0 0 0 1px rgba(242,239,233,.12), 0 20px 40px -16px rgba(0,0,0,.7);
  font-size: 13px; letter-spacing: .02em;
  opacity: 0; transform: translate(-50%, 16px); pointer-events: none;
  transition: opacity .4s var(--ease), transform .4s var(--ease);
}
.bk-toast.bk-is-visible { opacity: 1; transform: translate(-50%, 0); }
.bk-toast__dot { width: 18px; height: 18px; border-radius: 50%; background: var(--toast-color, var(--wd-accent)); box-shadow: 0 0 0 1px rgba(242,239,233,.25); }

/* ---------- Lightbox ---------- */
.bk-lightbox {
  width: 100vw; height: 100vh; height: 100dvh; max-width: none; max-height: none;
  margin: 0; padding: 0; border: 0;
  background: rgba(5,7,6,.96); color: var(--wd-text);
}
.bk-lightbox::backdrop { background: rgba(5,7,6,.7); }
.bk-lightbox[open] { animation: bk-lbIn .45s var(--ease); }
@keyframes bk-lbIn { from { opacity: 0; } to { opacity: 1; } }
.bk-lightbox__inner { position: relative; width: 100%; height: 100%; display: grid; place-items: center; padding: 72px clamp(16px, 7vw, 120px) 88px; }
.bk-lightbox__figure { display: grid; justify-items: center; gap: 18px; max-width: 100%; max-height: 100%; }
.bk-lightbox__img { max-width: 100%; max-height: calc(100dvh - 180px); width: auto; height: auto; object-fit: contain; animation: bk-lbImg .6s var(--ease); }
@keyframes bk-lbImg { from { opacity: 0; transform: scale(.98); } to { opacity: 1; transform: none; } }
.bk-lightbox__caption { display: flex; gap: 18px; font-size: 13px; color: var(--wd-muted); }
.bk-lightbox__caption span:first-child { color: var(--th-gold); font-variant-numeric: tabular-nums; }
.bk-lightbox__btn {
  position: absolute; width: 48px; height: 48px; border-radius: 50%;
  display: grid; place-items: center; font-size: 20px; line-height: 1;
  box-shadow: inset 0 0 0 1px rgba(242,239,233,.2);
  transition: background-color .3s var(--ease), color .3s var(--ease);
}
.bk-lightbox__btn:hover { background: var(--wd-text); color: var(--wd-bg); }
.bk-lightbox__close { top: 16px; right: 16px; font-size: 26px; }
.bk-lightbox__prev { left: 16px; top: 50%; transform: translateY(-50%); }
.bk-lightbox__next { right: 16px; top: 50%; transform: translateY(-50%); }
.bk-lightbox.bk-is-single .bk-lightbox__prev, .bk-lightbox.bk-is-single .bk-lightbox__next { display: none; }

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */
@media (max-width: 1280px) {
  .bk-menu__list { grid-template-columns: minmax(0, 1fr); grid-template-rows: none; grid-auto-flow: row; }
  .bk-hero__aside { position: static; width: auto; margin-top: clamp(28px, 4vw, 48px); grid-template-columns: auto 1fr; align-items: end; gap: 24px; }
}

@media (max-width: 1023px) {
  .bk { --header-h: 48px; --site-offset: 64px; }

  .bk-chapter__head--split { grid-template-columns: minmax(0, 1fr); align-items: start; gap: 28px; }
  .bk-chapter__head--split .bk-lead { justify-self: start; }

  .bk-hero__decor { width: 120vw; right: -50vw; top: 40%; }

  .bk-beginning__grid { grid-template-columns: minmax(0, 1fr); }
  .bk-word { grid-template-columns: minmax(0, 1fr); gap: 10px; padding-bottom: 18px; }
  .bk-word__note { grid-template-columns: auto 1fr; gap: 12px; max-width: 32em; }

  .bk-challenge__grid { grid-template-columns: minmax(0, 1fr); }
  .bk-challenge__sticky { position: static; }
  .bk-challenge__count { display: none; }
  .bk-challenge__list { padding-top: 0; padding-bottom: 0; }

  .bk-ideas { grid-template-columns: minmax(0, 1fr); }
  .bk-idea { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1fr); column-gap: 32px; align-items: start; padding: 32px 0; border-left: 0; border-bottom: 1px solid var(--line); }
  .bk-idea__photo { grid-row: 1 / span 6; margin: 0; }
  .bk-idea__art { width: 72px; margin: 0 0 14px; }

  /* Symbol: tabs instead of scroll-stepping */
  .bk-symbol__layout { grid-template-columns: minmax(0, 1fr); gap: 24px; }
  .bk-symbol__stage { position: static; min-height: 0; padding: 0; }
  .bk-symbol__figure { width: min(78vw, 440px); margin: 6% 0; }
  .bk-symbol__steps { padding: 0; }
  .bk-sstep { display: none; min-height: 0; opacity: 1; max-width: 40em; margin-inline: auto; text-align: center; }
  .bk-sstep.bk-is-active { display: flex; animation: bk-logoIn .6s var(--ease) both; }

  .bk-construct__pin { min-height: 0; padding-block: var(--section-y); }
  .bk-construct__grid { grid-template-columns: minmax(0, 1fr); }
  .bk-construct__figure { width: min(100%, 520px); }

  .bk-specimens { grid-template-columns: minmax(0, 1fr); }
  .bk-type-use { grid-template-columns: minmax(0, 1fr); }
  .bk-wordmark__notes { grid-template-columns: minmax(0, 1fr); gap: 12px; }

  .bk-cpanel__inner { grid-template-columns: minmax(0, 1fr); grid-template-areas: "role" "name" "meta"; align-content: end; }
  .bk-palette__grid { grid-template-columns: minmax(0, 1fr); }
  .bk-preview { position: static; order: -1; display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 20px; align-items: end; }
  .bk-preview__canvas { aspect-ratio: 4 / 3; }

  .bk-lsys__info { grid-template-columns: minmax(0, 1fr); }
  .bk-lsys__clear { border-left: 0; border-top: 1px solid var(--line); }
  .bk-lsys__logo[data-logo="primary"] { width: min(74vw, 620px); }
  .bk-lsys__logo[data-logo="alt-h"] { width: min(60vw, 460px); }
  .bk-lsys__logo[data-logo="alt-v"] { width: min(40vw, 260px); }
  .bk-avatars { grid-template-columns: minmax(0, 1fr); }

  .bk-digital__kb { grid-template-columns: minmax(0, 1fr); }
  .bk-devices { grid-template-columns: repeat(6, minmax(0, 1fr)); row-gap: 48px; }
  .bk-device--a { grid-column: 1 / span 3; margin-top: 8vh; }
  .bk-device--b { grid-column: 4 / span 3; }
  .bk-device--social { grid-column: 1 / -1; }

  .bk-gallery { grid-template-columns: repeat(6, minmax(0, 1fr)); grid-auto-flow: row dense; row-gap: 56px; }
  .bk-gitem--bag { grid-column: 1 / -1; }
  .bk-gitem--cards { grid-column: 4 / span 3; margin-top: 0; }
  .bk-gitem--caps { grid-column: 1 / span 3; margin-top: 12vh; }
  .bk-gitem--sign { grid-column: 1 / -1; margin-top: 0; }
  .bk-gitem--doy { grid-column: 1 / span 3; margin-top: 0; }
  .bk-gitem--folder { grid-column: 4 / span 3; margin-top: 10vh; }
  .bk-gitem--dropper { grid-column: 1 / span 3; }
  .bk-gitem--tote { grid-column: 4 / span 3; margin-top: 10vh; }
  .bk-gitem--tote .bk-gitem__frame { aspect-ratio: 4 / 5; }
  .bk-gitem--tote .bk-gitem__frame img { object-position: 52% 55%; }

}

@media (max-width: 767px) {
  .bk { --section-y: clamp(80px, 22vw, 120px); }
  .bk-menu-btn__label { font-size: 11px; }
  .bk-menu__title { font-size: 1.5rem; }
  .bk-menu__link { grid-template-columns: 36px 1fr; }
  .bk-menu__pl { display: none; }

  .bk-hero__top { flex-direction: column; gap: 4px; }
  .bk-hero__top-right { color: var(--wd-text); opacity: .7; }
  .bk-hero__title { letter-spacing: -.045em; }
  .bk-hero__title .bk-line:nth-child(2) { padding-left: 0; }
  .bk-hero__aside { grid-template-columns: minmax(0, 1fr); gap: 16px; }
  .bk-hero__logo { width: min(68vw, 260px); }
  .bk-hero__concept { display: none; }

  .bk-facts__row { grid-template-columns: minmax(0, 1fr); gap: 4px; }
  .bk-word__text { font-size: clamp(2.4rem, 12.6vw, 5.4rem); }

  .bk-ccard { padding: 24px 20px; }

  .bk-idea { grid-template-columns: minmax(0, 1fr); }
  .bk-idea__photo { grid-row: auto; margin: 0 0 24px; }
  .bk-idea__art { width: 64px; }
  .bk-interlude--light { align-items: start; }
  .bk-interlude--light .bk-interlude__media img { object-position: 74% 50%; }
  .bk-interlude--light .bk-interlude__veil { background: linear-gradient(180deg, rgba(242,239,233,.94) 0%, rgba(242,239,233,.78) 40%, rgba(242,239,233,0) 66%); }
  .bk-interlude--light .bk-interlude__quote { max-width: none; }
  .bk-interlude--light .bk-interlude__content { padding-top: calc(var(--chrome-h) + 32px); }

  .bk-symbol__tabs button { padding: 0 12px; font-size: 11px; }

  .bk-cpanel__name { font-size: clamp(2.4rem, 11vw, 3.8rem); }
  .bk-scale__list { grid-template-columns: repeat(7, minmax(0, 1fr)); }
  .bk-sw { height: 96px; padding: 6px; }
  .bk-sw__name { display: none; }
  .bk-sw__hex { font-size: 9px; writing-mode: vertical-rl; transform: rotate(180deg); align-self: flex-start; }
  .bk-scale--single .bk-scale__list { max-width: calc(100% / 7 * 3); }
  .bk-scale--single .bk-sw__hex { writing-mode: horizontal-tb; transform: none; font-size: 11px; }
  .bk-preview { grid-template-columns: minmax(0, 1fr); }

  .bk-lsys__controls { padding: 12px; }
  .bk-tabs { width: 100%; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .bk-tabs button { padding: 6px 4px; min-height: 48px; font-size: 10.5px; letter-spacing: .06em; line-height: 1.25; border-radius: 12px; }
  .bk-lsys__toggles { width: 100%; justify-content: space-between; }
  .bk-seg button { padding: 0 10px; font-size: 11px; }
  .bk-lsys__stage { min-height: 300px; padding: 56px 16px; }
  .bk-lsys__logo[data-logo="primary"] { width: 72vw; }
  .bk-lsys__logo[data-logo="alt-h"] { width: 62vw; }
  .bk-lsys__logo[data-logo="alt-v"] { width: 44vw; }

  .bk-hero-shot { width: 100%; }
  .bk-device--a { grid-column: 1 / span 3; margin-top: 40px; }
  .bk-device--b { grid-column: 4 / span 3; }

  .bk-gallery { grid-template-columns: minmax(0, 1fr); row-gap: 44px; }
  .bk-gallery .bk-gitem { grid-column: 1 / -1; margin-top: 0; }
  .bk-gitem--cards, .bk-gitem--folder { width: 82%; justify-self: end; }
  .bk-gitem--tote .bk-gitem__frame { aspect-ratio: 4 / 3; }
  .bk-gitem--caps, .bk-gitem--dropper { width: 86%; }

  .bk-principle { grid-template-columns: minmax(0, 1fr); gap: 6px; }

  .bk-values li { padding-inline: 16px; letter-spacing: .18em; }
  .bk-final__actions .bk-btn { width: 100%; }
  .bk-footer { flex-direction: column; align-items: flex-start; gap: 8px; }
  .bk-footer__mid { display: none; }
  .bk-lightbox__inner { padding: 64px 12px 96px; }
  .bk-lightbox__prev, .bk-lightbox__next { top: auto; bottom: 20px; transform: none; }
  .bk-lightbox__prev { left: calc(50% - 60px); }
  .bk-lightbox__next { right: calc(50% - 60px); }
  }

@media (max-width: 380px) {
  .bk-tabs button { font-size: 9.5px; }
  .bk-seg button { padding: 0 8px; }
  .bk-switch { font-size: 11px; letter-spacing: .06em; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html.bk-page:focus-within { scroll-behavior: auto; }
  :where(.bk) *, :where(.bk) *::before, :where(.bk) *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  .bk-scroll-cue__dot { animation: none; }
}

/* ==========================================================================
   WD Design — dopasowanie do strony (generator, 1.24.36)
   ========================================================================== */
.bk { position: relative; overflow-x: clip; }
.bk-sr { position: absolute; width: 1px; height: 1px; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
/* Próbki krojów marki jako krzywe: szerokość w em (skaluje się z font-size), wysokość z proporcji. */
.bk-curve { display: block; height: auto; max-width: 100%; overflow: visible; fill: currentColor; }
.bk-spec__aa .bk-curve { display: inline-block; vertical-align: top; }
.bk-spec__weights li { display: block; }
.bk-spec__weights .bk-curve { font-size: 1.15rem; }
.bk-type-use__narrow { display: none; }
@media (max-width: 600px) {
  .bk-type-use__wide { display: none; }
  .bk-type-use__narrow { display: block; }
}
/* Nagłówki strony (Nohemi): metryki inne niż Gayathri — wyrównanie słów między liniami. */
.bk-word__text { padding-top: .2em; }
/* Reguły motywu dla H1 stron (spany w kolorze tytułu, H1 35 px na telefonie) nie dotyczą okładki księgi. */
main .bk .bk-hero__dot { color: var(--th-gold); -webkit-text-fill-color: currentColor; }
@media (max-width: 720px) {
  main .bk h1.bk-hero__title { font-size: var(--fs-mega) !important; line-height: .86 !important; }
}
/* Hero (Dominik 23.10): nagłówek wyśrodkowany w poziomie, wiersze wyrównane do prawej; logo i hasło pod nim, do prawej krawędzi tytułu. */
.bk-hero__body { display: grid; justify-content: center; }
.bk-hero__title { width: fit-content; justify-self: end; margin-left: 0; text-align: right; }
.bk-hero__title .bk-line:nth-child(2) { padding-left: 0; }
.bk-hero__aside { position: static; width: auto; justify-self: end; justify-items: end; margin-top: clamp(20px, 2.4vw, 36px); grid-template-columns: auto; text-align: right; }
@media (max-width: 767px) {
  .bk { --fs-mega: clamp(2.5rem, 16vw, 4.4rem); }
  .bk-hero__aside { justify-self: end; }
}
/* Próbka „Aa” w masce: miejsce na lewy obrys litery. */
.bk-spec__aa .bk-mask { padding-left: .08em; margin-left: -.08em; }
/* Nohemi przy -0,05 em zlepia litery w dużych nazwach — luźniej, jak duże nagłówki strony (-0,045 em). */
.bk-cpanel__name { letter-spacing: -.035em; }
.bk-hero__title { letter-spacing: -.045em; }
/* 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-open .bk-site-header { z-index: 135; transform: none; opacity: 1; pointer-events: auto; }
.bk-menu-open .bk-site-header::before { background: var(--wd-bg); }
.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; }
/* Dominik 27.10: podpis cytatu na jasnym zdjęciu był nieczytelny — ciemniejszy, większy, z jasną poświatą. */
.bk-interlude--light .bk-interlude__quote cite { color: #4d3a1c; font-size: .875rem; font-weight: 600; text-shadow: 0 0 14px rgba(242,239,233,.95), 0 0 4px rgba(242,239,233,.9); }