:root {
  --ink: #111214;
  --ink-soft: #48505a;
  --paper: #f6f1e7;
  --chalk: #fffaf0;
  --asphalt: #0a0c0f;
  --graphite: #20262d;
  --graphite-soft: #3a424b;
  --steel: #b8c0c5;
  --aluminium: #e0e3df;
  --signal: #b32025;
  --signal-dark: #611014;
  --amber: #ff9f43;
  --glass: #9cc7d6;
  --shadow: 0 34px 100px rgba(5, 7, 10, 0.28);
  --stage-width: min(92vw, 1180px);
  --stage-height: min(58vw, 720px);
  --display: "DIN Condensed", "Oswald", "Avenir Next Condensed", "Franklin Gothic Medium", sans-serif;
  --sans: "Avenir Next", "Gill Sans", "Trebuchet MS", Verdana, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  min-width: 320px;
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 16% 14%, rgba(179, 32, 37, 0.16), transparent 29rem),
    radial-gradient(circle at 82% 3%, rgba(255, 159, 67, 0.14), transparent 30rem),
    linear-gradient(135deg, #fbf7ed 0%, var(--paper) 42%, #d8d0c2 100%);
  font-family: var(--sans);
  overflow-x: hidden;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  content: "";
  background-image:
    linear-gradient(rgba(17, 18, 20, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(17, 18, 20, 0.035) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(circle at 50% 16%, black 0, transparent 74%);
}

body::after {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  content: "";
  opacity: 0.42;
  background:
    repeating-linear-gradient(
      108deg,
      rgba(255, 255, 255, 0.14) 0,
      rgba(255, 255, 255, 0.14) 1px,
      transparent 1px,
      transparent 11px
    );
  mix-blend-mode: soft-light;
}

a {
  color: inherit;
}

.hero {
  min-height: 100svh;
  position: relative;
  display: grid;
  align-items: center;
  padding: 1.2rem clamp(1.1rem, 4vw, 4rem) 6rem;
  isolation: isolate;
}

.hero::before {
  position: absolute;
  inset: 13vh 4vw auto auto;
  width: min(58vw, 760px);
  aspect-ratio: 1.72 / 1;
  border: 1px solid rgba(17, 18, 20, 0.1);
  border-radius: 52% 48% 44% 56% / 55% 48% 52% 45%;
  content: "";
  background:
    radial-gradient(ellipse at 50% 75%, rgba(17, 18, 20, 0.18), transparent 38%),
    linear-gradient(105deg, transparent 0 23%, rgba(179, 32, 37, 0.2) 23% 43%, transparent 43% 58%, rgba(255, 159, 67, 0.18) 58% 76%, transparent 76%),
    linear-gradient(145deg, rgba(255, 255, 255, 0.22), rgba(255, 255, 255, 0.02));
  box-shadow: inset 0 0 78px rgba(255, 255, 255, 0.4);
  opacity: 0.78;
  z-index: -1;
}

.nav {
  position: absolute;
  inset: 1.4rem clamp(1.1rem, 4vw, 4rem) auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.76rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
}

.brand,
.nav__link {
  text-decoration: none;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.72rem;
  font-weight: 800;
}

.brand__mark {
  width: 2.35rem;
  aspect-ratio: 1.45 / 1;
  border: 1px solid rgba(17, 18, 20, 0.34);
  border-radius: 999px;
  background:
    radial-gradient(circle at 24% 72%, var(--ink) 0 10%, transparent 11%),
    radial-gradient(circle at 76% 72%, var(--ink) 0 10%, transparent 11%),
    linear-gradient(12deg, transparent 0 18%, rgba(179, 32, 37, 0.88) 19% 68%, transparent 69%);
}

.nav__link {
  border-bottom: 1px solid rgba(17, 18, 20, 0.35);
  padding-bottom: 0.25rem;
}

.hero__inner {
  width: min(940px, 100%);
  padding-top: 6rem;
}

.eyebrow,
.copy-panel__kicker {
  margin: 0 0 1.25rem;
  color: var(--signal);
  font-size: 0.74rem;
  font-weight: 800;
  letter-spacing: 0.28em;
  text-transform: uppercase;
}

h1,
h2 {
  font-family: var(--display);
  font-weight: 800;
  letter-spacing: -0.055em;
  text-transform: uppercase;
}

h1 {
  max-width: 10.5ch;
  margin: 0;
  font-size: clamp(4rem, 12vw, 10.2rem);
  line-height: 0.82;
}

.hero__copy {
  width: min(680px, 100%);
  margin: 2rem 0 0;
  color: var(--ink-soft);
  font-size: clamp(1rem, 1.35vw, 1.2rem);
  line-height: 1.8;
}

.hero__cta {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  min-height: 46px;
  margin-top: 2.4rem;
  border: 1px solid rgba(17, 18, 20, 0.28);
  border-radius: 999px;
  padding: 0.95rem 1.35rem;
  background: rgba(255, 255, 255, 0.28);
  box-shadow: 0 14px 42px rgba(17, 18, 20, 0.1);
  color: var(--ink);
  font-size: 0.72rem;
  font-weight: 900;
  letter-spacing: 0.22em;
  text-decoration: none;
  text-transform: uppercase;
  backdrop-filter: blur(12px);
}

.hero__cta::after {
  content: "";
  width: 1.65rem;
  height: 1px;
  background: currentColor;
}

.hero__cta:focus-visible,
.nav__link:focus-visible,
.brand:focus-visible {
  outline: 3px solid rgba(179, 32, 37, 0.46);
  outline-offset: 5px;
}

.assembly {
  min-height: 820vh;
  position: relative;
}

.assembly__sticky {
  min-height: 100svh;
  position: sticky;
  top: 0;
  display: grid;
  place-items: center;
  overflow: hidden;
  padding: clamp(1rem, 3vw, 3rem);
}

.assembly__sticky::before {
  position: absolute;
  inset: 7% 5%;
  border: 1px solid rgba(17, 18, 20, 0.09);
  border-radius: 2.4rem;
  content: "";
  background:
    radial-gradient(ellipse at 50% 58%, rgba(17, 18, 20, 0.16), transparent 31rem),
    radial-gradient(circle at 72% 20%, rgba(179, 32, 37, 0.16), transparent 19rem),
    linear-gradient(110deg, rgba(255, 255, 255, 0.3), rgba(255, 255, 255, 0.05));
  box-shadow: inset 0 0 80px rgba(255, 255, 255, 0.18);
}

.assembly__sticky::after {
  position: absolute;
  inset: auto 8% 9%;
  height: 34%;
  content: "";
  background:
    linear-gradient(180deg, transparent, rgba(10, 12, 15, 0.1) 38%, rgba(10, 12, 15, 0.22)),
    repeating-linear-gradient(90deg, rgba(255, 255, 255, 0.06) 0 1px, transparent 1px 78px);
  transform: perspective(900px) rotateX(62deg);
  transform-origin: bottom;
  filter: blur(0.2px);
  opacity: 0.55;
}

.chapter-index {
  position: absolute;
  top: clamp(5rem, 9vh, 7rem);
  left: clamp(1.2rem, 4vw, 4rem);
  display: flex;
  align-items: center;
  gap: 0.85rem;
  color: rgba(17, 18, 20, 0.58);
  font-family: var(--display);
  font-size: 1.05rem;
  font-weight: 800;
  letter-spacing: 0.18em;
  z-index: 5;
}

.chapter-index i {
  display: block;
  width: 5rem;
  height: 1px;
  background: rgba(17, 18, 20, 0.24);
}

.vehicle-stage {
  width: var(--stage-width);
  height: max(420px, var(--stage-height));
  position: relative;
  z-index: 2;
  transform-style: preserve-3d;
  perspective: 1700px;
  transform: translateY(var(--camera-lift, 0)) rotateX(calc((var(--assembly-progress, 0) - 0.5) * -2.5deg)) rotateY(calc((var(--assembly-progress, 0) - 0.5) * 4deg));
  transition: transform 120ms linear;
}

.vehicle-stage__floor {
  position: absolute;
  left: 7%;
  right: 7%;
  bottom: 11%;
  height: 20%;
  border-radius: 50%;
  background:
    radial-gradient(ellipse at 50% 52%, rgba(4, 5, 7, 0.38), rgba(4, 5, 7, 0.12) 44%, transparent 73%),
    radial-gradient(ellipse at 42% 42%, rgba(255, 255, 255, 0.26), transparent 52%);
  filter: blur(10px);
  opacity: calc(0.25 + var(--assembly-progress, 0) * 0.58);
  transform: translateZ(-180px);
}

.vehicle-piece {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  opacity: 0;
  transform-origin: 50% 55%;
  transform-style: preserve-3d;
  will-change: transform, opacity, filter;
  filter: drop-shadow(0 34px 34px rgba(3, 4, 6, 0.22)) blur(4px) saturate(0.9);
}

.vehicle-piece--finish {
  mix-blend-mode: screen;
}

.copy-layer {
  position: absolute;
  inset: 0;
  z-index: 4;
  pointer-events: none;
}

.copy-panel {
  position: absolute;
  top: 50%;
  width: min(34rem, 36vw);
  min-height: 15rem;
  padding: clamp(1.25rem, 2vw, 2rem);
  border: 1px solid rgba(17, 18, 20, 0.12);
  border-radius: 1.45rem;
  background:
    linear-gradient(135deg, rgba(255, 250, 240, 0.78), rgba(231, 224, 213, 0.5)),
    radial-gradient(circle at 20% 0%, rgba(179, 32, 37, 0.11), transparent 15rem);
  box-shadow: var(--shadow);
  opacity: 0;
  transform: translate3d(0, -42%, 0);
  backdrop-filter: blur(22px);
  will-change: transform, opacity;
}

.copy-panel--left {
  left: clamp(1rem, 4vw, 4.5rem);
}

.copy-panel--right {
  right: clamp(1rem, 4vw, 4.5rem);
}

.copy-panel h2 {
  margin: 0;
  font-size: clamp(2.25rem, 4.1vw, 4.7rem);
  line-height: 0.9;
}

.copy-panel p:not(.copy-panel__kicker) {
  margin: 1.2rem 0 0;
  color: var(--ink-soft);
  font-size: clamp(0.96rem, 1.05vw, 1.08rem);
  line-height: 1.75;
}

.finale {
  min-height: 82svh;
  display: grid;
  align-content: center;
  padding: clamp(4rem, 10vw, 10rem) clamp(1.1rem, 8vw, 8rem);
  background:
    radial-gradient(circle at 78% 32%, rgba(179, 32, 37, 0.24), transparent 27rem),
    radial-gradient(circle at 20% 84%, rgba(255, 159, 67, 0.12), transparent 22rem),
    linear-gradient(135deg, #0a0c0f, #191f26 54%, #060708);
  color: var(--paper);
}

.finale h2 {
  width: min(940px, 100%);
  margin: 0;
  font-size: clamp(3.2rem, 8.5vw, 8rem);
  line-height: 0.88;
}

.finale p:not(.eyebrow) {
  width: min(700px, 100%);
  margin: 1.6rem 0 0;
  color: rgba(246, 241, 231, 0.76);
  font-size: clamp(1rem, 1.25vw, 1.18rem);
  line-height: 1.75;
}

.hero__cta--dark {
  width: fit-content;
  border-color: rgba(246, 241, 231, 0.28);
  color: var(--paper);
  background: rgba(246, 241, 231, 0.08);
}

@media (max-width: 1040px) {
  :root {
    --stage-width: min(96vw, 940px);
    --stage-height: min(70vw, 660px);
  }

  .copy-panel {
    width: min(31rem, 40vw);
  }
}

@media (max-width: 820px) {
  :root {
    --stage-width: 112vw;
    --stage-height: 72svh;
  }

  .nav__link {
    display: none;
  }

  .assembly__sticky {
    place-items: start center;
    padding-top: 10svh;
  }

  .vehicle-stage {
    margin-top: 2svh;
    height: 58svh;
  }

  .copy-panel {
    top: auto;
    bottom: 4svh;
    left: 1rem;
    right: 1rem;
    width: auto;
    min-height: 0;
  }

  .copy-panel--left,
  .copy-panel--right {
    left: 1rem;
    right: 1rem;
  }

  .copy-panel h2 {
    font-size: clamp(2rem, 8.6vw, 3.2rem);
  }

  .chapter-index {
    top: 4.7rem;
  }
}

@media (max-width: 520px) {
  h1 {
    font-size: clamp(3.2rem, 17vw, 5.2rem);
  }

  .vehicle-stage {
    width: 128vw;
    margin-left: -14vw;
  }

  .copy-panel {
    padding: 1.05rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .assembly {
    min-height: auto;
  }

  .assembly__sticky {
    position: relative;
    min-height: 120svh;
  }

  .vehicle-stage {
    transform: none !important;
  }

  .vehicle-piece {
    opacity: 1 !important;
    transform: none !important;
    filter: drop-shadow(0 24px 24px rgba(3, 4, 6, 0.18)) !important;
  }

  .copy-layer {
    position: static;
    display: grid;
    gap: 1rem;
    width: min(760px, 100%);
    margin-top: 1rem;
  }

  .copy-panel {
    position: static;
    width: 100%;
    opacity: 1 !important;
    transform: none !important;
  }
}