:root {
  --black: #050504;
  --void: #090806;
  --panel: rgba(13, 12, 10, .84);
  --cream: #f4efe4;
  --paper: #d9c49b;
  --paper-deep: #bda77e;
  --tan: #d8bd8a;
  --line: rgba(216, 189, 138, .28);
  --line-soft: rgba(216, 189, 138, .12);
  --muted: #9f967f;
  --shadow: rgba(0, 0, 0, .68);
  --ease: cubic-bezier(.22, .8, .26, 1);
}

* {
  box-sizing: border-box;
}

html {
  min-height: 100%;
  background: var(--black);
  color-scheme: dark;
}

body {
  margin: 0;
  min-height: 100vh;
  overflow-x: hidden;
  background: var(--black);
  color: var(--cream);
  font-family: "Space Grotesk", system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

button,
a {
  font: inherit;
}

button {
  color: inherit;
}

.skip-link {
  position: fixed;
  top: -4rem;
  left: 1rem;
  z-index: 20;
  background: var(--cream);
  color: var(--black);
  padding: .75rem 1rem;
}

.skip-link:focus {
  top: 1rem;
}

.playbook-shell {
  position: relative;
  min-height: 100svh;
  overflow: hidden;
  display: grid;
  grid-template-columns: minmax(210px, 18vw) minmax(0, 1fr);
  grid-template-rows: auto minmax(0, 1fr) auto;
  gap: clamp(1rem, 2vw, 1.8rem);
  padding: clamp(1rem, 2vw, 1.7rem);
  isolation: isolate;
  background:
    radial-gradient(circle at 16% 6%, rgba(255, 227, 166, .18), transparent 14rem),
    radial-gradient(circle at 78% 58%, rgba(216, 189, 138, .06), transparent 24rem),
    linear-gradient(180deg, #11100d, #050504 38%, #030302);
}

.playbook-shell::before {
  content: "";
  position: absolute;
  inset: 5rem 0 0;
  z-index: -2;
  background:
    linear-gradient(rgba(216, 189, 138, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(216, 189, 138, .03) 1px, transparent 1px);
  background-size: 72px 72px;
  transform: perspective(700px) rotateX(58deg) translateY(2rem);
  transform-origin: center top;
  opacity: .52;
}

.playbook-shell::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    linear-gradient(90deg, rgba(0, 0, 0, .46), transparent 28%, transparent 72%, rgba(0, 0, 0, .55)),
    radial-gradient(ellipse at center, transparent 32%, rgba(0, 0, 0, .58) 88%);
}

.playbook-topbar {
  grid-column: 1 / -1;
  height: 3.1rem;
  display: grid;
  grid-template-columns: minmax(170px, 1fr) auto minmax(170px, 1fr);
  align-items: center;
  gap: 1rem;
  color: var(--tan);
  font-family: "Space Mono", ui-monospace, monospace;
  text-transform: uppercase;
  letter-spacing: .14em;
  font-size: clamp(.6rem, .85vw, .78rem);
}

.playbook-brand {
  color: var(--tan);
  text-decoration: none;
  font-size: clamp(.82rem, 1.25vw, 1.35rem);
  font-weight: 700;
  line-height: 1.1;
}

.playbook-topbar p,
.playbook-topbar span {
  margin: 0;
}

.playbook-topbar p {
  justify-self: center;
  color: var(--cream);
  font-weight: 700;
}

.playbook-topbar span {
  justify-self: end;
  color: #b79d6f;
}

.table-field {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: -1;
}

.lamp-glow {
  position: absolute;
  left: -2rem;
  top: -3rem;
  width: 18rem;
  height: 12rem;
  border-radius: 55%;
  background: radial-gradient(circle at 48% 58%, rgba(255, 230, 166, .42), rgba(216, 189, 138, .1) 24%, transparent 64%);
  filter: blur(1px);
}

.lamp-glow::before {
  content: "";
  position: absolute;
  left: .8rem;
  top: -2rem;
  width: 14rem;
  height: 7rem;
  border: 1px solid rgba(216, 189, 138, .26);
  border-bottom: 5px solid rgba(255, 230, 166, .82);
  border-radius: 0 0 8rem 8rem;
  transform: rotate(11deg);
  background: rgba(0, 0, 0, .42);
}

.blueprint-sheet,
.model-blocks,
.desk-card,
.sticky-note,
.wire-prism {
  position: absolute;
  border: 1px solid var(--line-soft);
  box-shadow: 0 24px 70px rgba(0, 0, 0, .45);
}

.blueprint-sheet {
  background:
    linear-gradient(rgba(216, 189, 138, .08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(216, 189, 138, .08) 1px, transparent 1px),
    rgba(47, 39, 28, .34);
  background-size: 26px 26px;
}

.sheet-left {
  left: -2rem;
  bottom: -1rem;
  width: 20rem;
  height: 13rem;
  transform: rotate(-8deg);
}

.sheet-back {
  left: 31vw;
  top: 4.2rem;
  width: 38vw;
  height: 8rem;
  transform: rotate(3deg);
}

.model-blocks {
  right: 3vw;
  top: 7rem;
  width: 10rem;
  height: 8rem;
  background:
    linear-gradient(90deg, rgba(216, 189, 138, .14) 33%, transparent 33% 38%, rgba(216, 189, 138, .1) 38% 66%, transparent 66%),
    linear-gradient(0deg, rgba(216, 189, 138, .16) 35%, transparent 35% 42%, rgba(216, 189, 138, .1) 42% 72%, transparent 72%),
    rgba(94, 78, 54, .22);
}

.desk-card {
  right: 5vw;
  bottom: 2.5rem;
  padding: 1.5rem 1.8rem;
  transform: rotate(8deg);
  color: var(--tan);
  background: rgba(8, 7, 5, .8);
  font-family: "Space Mono", monospace;
  text-transform: uppercase;
  letter-spacing: .18em;
  line-height: 1.8;
}

.sticky-note {
  left: 4vw;
  bottom: 2rem;
  width: 10rem;
  min-height: 7rem;
  padding: 1.1rem;
  transform: rotate(-10deg);
  color: #17120a;
  background: #c4a460;
  font-size: 1.15rem;
  line-height: 1.25;
}

.wire-prism {
  right: 9vw;
  top: 42%;
  width: 10rem;
  height: 6rem;
  border: 0;
  box-shadow: none;
  background:
    linear-gradient(25deg, transparent 48%, rgba(216, 189, 138, .7) 49% 51%, transparent 52%),
    linear-gradient(155deg, transparent 48%, rgba(216, 189, 138, .45) 49% 51%, transparent 52%),
    linear-gradient(90deg, transparent 48%, rgba(216, 189, 138, .34) 49% 51%, transparent 52%);
  opacity: .7;
}

.contents-rail {
  grid-column: 1;
  grid-row: 2;
  align-self: center;
  min-height: min(78svh, 760px);
  display: grid;
  align-content: start;
  gap: 1.2rem;
  padding: clamp(1rem, 1.7vw, 1.45rem);
  border: 1px solid rgba(216, 189, 138, .22);
  background: linear-gradient(180deg, rgba(8, 8, 7, .92), rgba(12, 10, 8, .76));
  box-shadow: 0 34px 90px rgba(0, 0, 0, .58);
}

.rail-kicker,
.page-kicker,
.page-number,
.flip-instructions,
.contents-list b {
  font-family: "Space Mono", ui-monospace, monospace;
  text-transform: uppercase;
  letter-spacing: .12em;
}

.rail-kicker,
.page-kicker {
  margin: 0 0 .65rem;
  color: #8c7957;
  font-size: .68rem;
}

.contents-rail h1 {
  margin: 0 0 .65rem;
  color: var(--tan);
  font-size: clamp(1.65rem, 2.2vw, 2.5rem);
  line-height: 1.05;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.contents-rail p {
  margin: 0;
  color: #a8a091;
  line-height: 1.55;
  font-size: .9rem;
}

.contents-list {
  display: grid;
  gap: .15rem;
}

.contents-list button {
  width: 100%;
  display: grid;
  grid-template-columns: 2.1rem 1fr;
  gap: .65rem;
  align-items: center;
  min-height: 2.55rem;
  padding: .45rem .35rem;
  border: 1px solid transparent;
  border-left: 2px solid transparent;
  color: #847d71;
  background: transparent;
  text-align: left;
  cursor: pointer;
}

.contents-list button:hover,
.contents-list button:focus-visible,
.contents-list button[aria-current="true"] {
  color: var(--cream);
  border-color: rgba(216, 189, 138, .16);
  border-left-color: var(--tan);
  background: rgba(216, 189, 138, .07);
}

.contents-list b {
  color: var(--tan);
  font-size: .68rem;
  font-weight: 400;
}

.contents-list span {
  font-size: .78rem;
}

.book-area {
  grid-column: 2;
  grid-row: 2;
  position: relative;
  min-width: 0;
  align-self: center;
  display: grid;
  place-items: center;
}

.open-book {
  position: relative;
  width: min(1050px, 100%);
  min-height: min(74svh, 720px);
  border-radius: 4px;
  filter: drop-shadow(0 48px 80px rgba(0, 0, 0, .62));
}

.open-book::before {
  content: "";
  position: absolute;
  inset: .7rem 2.4rem -1rem;
  z-index: -1;
  border: 1px solid rgba(216, 189, 138, .18);
  background: rgba(9, 8, 6, .78);
  box-shadow: inset 0 0 0 1px rgba(216, 189, 138, .05);
}

.spread {
  position: absolute;
  inset: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  opacity: 0;
  transform: translateX(1.4rem) scale(.99);
  pointer-events: none;
  transition: opacity .28s var(--ease), transform .34s var(--ease);
}

.spread.is-active {
  opacity: 1;
  transform: translateX(0) scale(1);
  pointer-events: auto;
}

.spread.is-exiting-left {
  transform: translateX(-1.4rem) scale(.99);
}

.book-page {
  min-height: min(74svh, 720px);
  position: relative;
  display: grid;
  align-content: center;
  overflow: hidden;
  padding: clamp(1.5rem, 4vw, 3.2rem);
}

.book-page::before {
  content: "";
  position: absolute;
  inset: 1.35rem;
  border: 1px solid currentColor;
  opacity: .18;
  pointer-events: none;
}

.dark-page {
  color: var(--tan);
  background:
    radial-gradient(circle at 55% 48%, rgba(216, 189, 138, .08), transparent 34%),
    linear-gradient(135deg, #14120e, #060605 70%);
  border-radius: 5px 0 0 5px;
  box-shadow: inset -18px 0 28px rgba(0, 0, 0, .38);
}

.light-page {
  color: #1b150d;
  background:
    linear-gradient(90deg, rgba(0, 0, 0, .14), transparent 8%),
    radial-gradient(circle at 80% 20%, rgba(255, 255, 255, .24), transparent 30%),
    linear-gradient(180deg, #dec99f, #c7ad7e);
  border-radius: 0 5px 5px 0;
  box-shadow: inset 18px 0 24px rgba(79, 57, 28, .24);
}

.page-number {
  position: absolute;
  left: clamp(1.5rem, 4vw, 3.2rem);
  top: clamp(1.5rem, 4vw, 3.2rem);
  color: var(--tan);
  font-size: .76rem;
}

.dark-page h2 {
  margin: 0 0 1.3rem;
  color: var(--cream);
  font-size: clamp(2.35rem, 4.05vw, 4.65rem);
  line-height: .94;
  font-weight: 400;
  letter-spacing: .03em;
  text-transform: uppercase;
}

.dark-page h2.title-fit {
  max-width: 7.8em;
}

.dark-page h2.title-orientation {
  font-size: clamp(2.15rem, 3.55vw, 4.15rem);
}

.spread-lede {
  max-width: 38ch;
  margin: 0 0 2rem;
  color: #d8c9aa;
  line-height: 1.65;
}

.metaphor-visual {
  position: relative;
  width: min(100%, 420px);
  min-height: 220px;
  border: 1px solid rgba(216, 189, 138, .28);
  background:
    linear-gradient(rgba(216, 189, 138, .05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(216, 189, 138, .05) 1px, transparent 1px);
  background-size: 28px 28px;
  overflow: hidden;
}

.visual-threshold span {
  position: absolute;
  left: 18%;
  right: 18%;
  border: 1px solid rgba(216, 189, 138, .38);
  transform: perspective(520px) rotateX(58deg);
}

.visual-threshold span:nth-child(1) { bottom: 18%; height: 38%; }
.visual-threshold span:nth-child(2) { bottom: 26%; height: 48%; left: 27%; right: 27%; }
.visual-threshold span:nth-child(3) { bottom: 35%; height: 58%; left: 36%; right: 36%; }
.visual-threshold i,
.visual-threshold b {
  position: absolute;
  color: #ddc18a;
  font-family: "Space Mono", monospace;
  font-size: .78rem;
  font-style: normal;
}
.visual-threshold i { left: 8%; bottom: 22%; }
.visual-threshold b { right: 8%; top: 25%; font-weight: 400; }

.visual-matrix {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: rgba(216, 189, 138, .18);
  padding: 1px;
}

.visual-matrix span,
.visual-plays span,
.visual-loop span,
.visual-room span {
  display: grid;
  place-items: center;
  min-height: 58px;
  padding: .8rem;
  color: #d8bd8a;
  background: rgba(5, 5, 4, .86);
  font-family: "Space Mono", monospace;
  font-size: .68rem;
  text-transform: uppercase;
  letter-spacing: .08em;
}

.visual-matrix span:last-child {
  grid-column: 1 / -1;
}

.visual-arc span {
  position: absolute;
  width: 10px;
  height: 10px;
  border: 1px solid var(--tan);
  background: var(--black);
  border-radius: 50%;
}

.visual-arc::before,
.visual-moves::before,
.visual-room::before {
  content: "";
  position: absolute;
  inset: 28% 10% 28% 10%;
  border: 1px solid rgba(216, 189, 138, .35);
  transform: skewX(-18deg);
}

.visual-arc span:nth-child(1) { left: 12%; top: 62%; }
.visual-arc span:nth-child(2) { left: 36%; top: 38%; }
.visual-arc span:nth-child(3) { left: 62%; top: 48%; }
.visual-arc span:nth-child(4) { right: 12%; top: 25%; }

.visual-plays {
  display: flex;
  align-items: end;
  gap: 1px;
  padding: 2.2rem 1.2rem;
}

.visual-plays span {
  flex: 1;
  min-height: 80px;
}

.visual-plays span:nth-child(2) {
  min-height: 140px;
}

.visual-moves span {
  position: absolute;
  width: 42%;
  height: 1px;
  background: var(--tan);
  transform-origin: left center;
}

.visual-moves span:nth-child(1) { left: 13%; top: 36%; transform: rotate(18deg); }
.visual-moves span:nth-child(2) { left: 18%; top: 58%; transform: rotate(-12deg); }
.visual-moves span:nth-child(3) { left: 47%; top: 44%; transform: rotate(33deg); }
.visual-moves span:nth-child(4) { left: 45%; top: 68%; transform: rotate(-24deg); }

.visual-assets span {
  position: absolute;
  width: 38%;
  height: 46%;
  border: 1px solid rgba(216, 189, 138, .42);
  background: rgba(216, 189, 138, .04);
}

.visual-assets span:nth-child(1) { left: 12%; top: 18%; }
.visual-assets span:nth-child(2) { left: 30%; top: 30%; }
.visual-assets span:nth-child(3) { left: 49%; top: 42%; }

.visual-loop {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  align-items: center;
  gap: .4rem;
  padding: 1rem;
}

.visual-loop span {
  border-radius: 50%;
  aspect-ratio: 1;
  min-height: 0;
}

.visual-room {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  padding: 1px;
  background: rgba(216, 189, 138, .18);
}

.light-page .page-kicker {
  color: #5d4526;
}

.example-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 1.2rem;
}

.example-list li {
  position: relative;
  padding-left: 1.2rem;
  line-height: 1.55;
}

.example-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .55rem;
  width: .42rem;
  height: .42rem;
  border: 1px solid #1b150d;
  transform: rotate(45deg);
}

.example-list strong {
  display: block;
  margin-bottom: .2rem;
  color: #070604;
}

blockquote {
  margin: 2rem 0 0;
  padding: 1rem 1.2rem;
  border: 1px solid rgba(27, 21, 13, .24);
  color: #21190f;
  font-weight: 700;
}

.book-cta {
  display: inline-flex;
  width: fit-content;
  margin-top: 1.6rem;
  padding: .82rem 1rem;
  border: 1px solid #1b150d;
  color: #1b150d;
  text-decoration: none;
  font-weight: 800;
}

.page-arrow {
  position: absolute;
  z-index: 5;
  top: 50%;
  width: 3.4rem;
  height: 3.4rem;
  overflow: hidden;
  border: 1px solid rgba(216, 189, 138, .34);
  border-radius: 50%;
  color: transparent;
  background: rgba(0, 0, 0, .78);
  cursor: pointer;
  box-shadow: 0 12px 40px rgba(0, 0, 0, .5);
}

.page-arrow::before {
  content: "";
  position: absolute;
  inset: 1.05rem;
  border-top: 2px solid var(--tan);
  border-left: 2px solid var(--tan);
}

.page-arrow-prev {
  left: max(.2rem, calc(50% - 580px));
  transform: translate(-70%, -50%);
}

.page-arrow-prev::before {
  transform: translateX(.2rem) rotate(-45deg);
}

.page-arrow-next {
  right: max(.2rem, calc(50% - 580px));
  transform: translate(70%, -50%);
}

.page-arrow-next::before {
  transform: translateX(-.2rem) rotate(135deg);
}

.page-arrow:hover,
.page-arrow:focus-visible {
  border-color: var(--tan);
  background: rgba(16, 13, 9, .92);
}

.page-arrow:disabled {
  opacity: .28;
  cursor: default;
}

.flip-instructions {
  grid-column: 2;
  grid-row: 3;
  justify-self: center;
  display: flex;
  gap: 1rem;
  align-items: center;
  padding: .7rem 1rem;
  border: 1px solid rgba(216, 189, 138, .16);
  color: #8f866f;
  background: rgba(3, 3, 2, .64);
  font-size: .68rem;
}

.flip-instructions p {
  margin: 0;
}

.flip-instructions span {
  color: var(--tan);
}

@media (max-width: 1060px) {
  .playbook-shell {
    grid-template-columns: 1fr;
    overflow-y: auto;
  }

  .playbook-topbar {
    grid-template-columns: 1fr;
    height: auto;
    text-align: center;
  }

  .playbook-topbar span,
  .playbook-topbar p,
  .playbook-brand {
    justify-self: center;
  }

  .contents-rail,
  .book-area,
  .flip-instructions {
    grid-column: 1;
    grid-row: auto;
  }

  .contents-rail {
    min-height: auto;
    align-self: stretch;
    position: relative;
    z-index: 4;
  }

  .book-area {
    z-index: 2;
  }

  .contents-list {
    display: flex;
    overflow-x: auto;
    padding-bottom: .3rem;
  }

  .contents-list button {
    min-width: 170px;
  }

  .page-arrow-prev {
    left: 1rem;
    transform: translate(0, -50%);
  }

  .page-arrow-next {
    right: 1rem;
    transform: translate(0, -50%);
  }
}

@media (max-width: 720px) {
  .playbook-shell {
    min-height: 100vh;
    padding: .75rem;
    gap: .75rem;
  }

  .table-field {
    display: none;
  }

  .contents-rail {
    padding: .85rem;
  }

  .contents-rail h1 {
    font-size: 1.5rem;
  }

  .open-book {
    min-height: 0;
    width: 100%;
  }

  .spread {
    position: relative;
    grid-template-columns: 1fr;
  }

  .spread:not(.is-active) {
    display: none;
  }

  .book-page {
    min-height: auto;
    padding: 4.25rem 1.15rem 1.3rem;
  }

  .dark-page,
  .light-page {
    border-radius: 4px;
  }

  .dark-page {
    min-height: 560px;
  }

  .dark-page h2 {
    font-size: clamp(2.35rem, 12vw, 3.55rem);
  }

  .dark-page h2.title-fit {
    max-width: 7.8em;
  }

  .dark-page h2.title-orientation {
    font-size: clamp(1.95rem, 9.4vw, 2.9rem);
  }

  .metaphor-visual {
    min-height: 190px;
  }

  .page-arrow {
    top: 48%;
    width: 2.8rem;
    height: 2.8rem;
  }

  .page-arrow-prev {
    left: .15rem;
  }

  .page-arrow-next {
    right: .15rem;
  }

  .flip-instructions {
    width: 100%;
    justify-content: space-between;
    gap: .75rem;
    font-size: .6rem;
  }
}