/* ============ UPRIGHT CO. — two tones, no third ============ */
:root {
  --ink: #060606;
  --paper: #ffffff;
  --mist: #8b8b8b;
  --hairline: #e8e8e8;
  --ghost: #f4f4f4;
  --display: "Anton", sans-serif;
  --body: "Instrument Sans", sans-serif;
  --mono: "IBM Plex Mono", monospace;
  --gutter: clamp(1.25rem, 4vw, 4rem);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--body);
  background: var(--paper);
  color: var(--ink);
  line-height: 1.55;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }

/* ---------- the spine ---------- */
#spine {
  position: fixed;
  top: 0; left: clamp(6px, 1.2vw, 18px);
  height: 100vh; width: 60px;
  color: var(--ink);
  opacity: 0.9;
  z-index: 5;
  pointer-events: none;
}
@media (max-width: 720px) { #spine { display: none; } }

/* ---------- header ---------- */
.site-head {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  padding: 1rem var(--gutter);
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--hairline);
}
.wordmark {
  font-family: var(--display);
  font-size: 1.35rem;
  letter-spacing: 0.04em;
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
}
.wordmark span { color: var(--mist); }
.wordmark .mark { width: 26px; height: 26px; border-radius: 6px; }
.head-nav { display: flex; gap: 2rem; }
.head-nav a {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s;
}
.head-nav a:hover, .head-nav a:focus-visible { border-color: var(--ink); }
.head-cta {
  white-space: nowrap;
  font-family: var(--mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 0.55rem 1.1rem;
  background: var(--ink);
  color: var(--paper);
  transition: transform 0.15s ease;
}
.head-cta:hover { transform: translateY(-2px); }
@media (max-width: 720px) { .head-nav { display: none; } }

/* ---------- hero ---------- */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  align-items: center;
  min-height: calc(100vh - 65px);
  padding: 3rem var(--gutter) 4rem;
  gap: 2rem;
}
.eyebrow {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--mist);
  margin-bottom: 1.25rem;
}
.hero-title {
  font-family: var(--display);
  font-size: clamp(4rem, 13vw, 11.5rem);
  line-height: 0.92;
  letter-spacing: 0.01em;
  text-transform: uppercase;
}
.hero-title .line { display: block; overflow: hidden; }
.hero-title .line > span {
  display: inline-block;
  transform: translateY(110%);
  animation: riseUp 0.9s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.hero-title .line:nth-child(2) > span { animation-delay: 0.12s; }
@keyframes riseUp { to { transform: translateY(0); } }

.hero-sub {
  max-width: 34rem;
  margin-top: 1.75rem;
  font-size: clamp(1rem, 1.4vw, 1.2rem);
  color: var(--ink);
}
.hero-actions { display: flex; gap: 1rem; margin-top: 2.25rem; flex-wrap: wrap; }

.btn {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 0.95rem 1.8rem;
  border: 1px solid var(--ink);
  cursor: pointer;
  transition: transform 0.15s ease, background 0.2s, color 0.2s;
}
.btn-solid { background: var(--ink); color: var(--paper); }
.btn-solid:hover { transform: translateY(-2px); }
.btn-ghost { background: transparent; color: var(--ink); }
.btn-ghost:hover { background: var(--ink); color: var(--paper); }

/* ---------- FIG. 01 — annotated spine profile ---------- */
.stage {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  perspective: 1100px;
  min-height: 420px;
}
.figure-tilt {
  transform-style: preserve-3d;
  transform: rotateX(4deg) rotateY(-8deg);
  transition: transform 0.35s ease-out;
  width: min(100%, 460px);
}
.fig { width: 100%; height: auto; color: var(--ink); }
.fig-mono {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  fill: var(--mist);
}
.fig-ruler { opacity: 0.65; }
.fig-readout {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  border-top: 1px solid var(--ink);
  margin-top: 0.75rem;
  padding-top: 0.6rem;
}
.readout-label {
  font-family: var(--mono);
  font-size: 0.66rem;
  letter-spacing: 0.2em;
  color: var(--mist);
}
#angleReadout {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 1.4rem;
  font-variant-numeric: tabular-nums;
}
@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; }
  .stage { min-height: 340px; order: 2; }
}

/* ---------- readout ticker ---------- */
.marquee {
  overflow: hidden;
  background: var(--ink);
  color: var(--paper);
  padding: 0.7rem 0;
  border-block: 1px solid var(--ink);
}
.marquee-track {
  display: flex;
  width: max-content;
  animation: slide 30s linear infinite;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  white-space: nowrap;
}
@keyframes slide { to { transform: translateX(-50%); } }

/* ---------- shared section scaffolding ---------- */
section { position: relative; }
.side-label {
  position: absolute;
  top: 4rem;
  left: calc(var(--gutter) * 0.35);
  writing-mode: vertical-rl;
  transform: rotate(180deg);
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.28em;
  color: var(--mist);
}
.side-label-inverse { color: color-mix(in srgb, var(--paper) 45%, transparent); }
@media (max-width: 720px) { .side-label { display: none; } }

h2 {
  font-family: var(--display);
  font-size: clamp(2.2rem, 5.4vw, 4.4rem);
  line-height: 1.02;
  text-transform: uppercase;
  letter-spacing: 0.01em;
}

/* reveal on scroll */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.is-in { opacity: 1; transform: none; }

/* measurement-ruler section divider */
.problem::before,
.promise::before {
  content: "";
  display: block;
  height: 9px;
  margin-bottom: clamp(3rem, 7vw, 6rem);
  border-top: 1px solid var(--ink);
  background-image: repeating-linear-gradient(
    90deg,
    var(--ink) 0 1px,
    transparent 1px 28px
  );
  background-size: 100% 9px;
  background-repeat: no-repeat;
}

/* ---------- problem ---------- */
.problem { padding: clamp(1rem, 2vw, 2rem) var(--gutter) clamp(4rem, 9vw, 8rem); }
.problem-inner { max-width: 68rem; margin-inline: auto; }
.problem-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  margin-top: 2.5rem;
  font-size: 1.05rem;
}
.stat-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  border-top: 1px solid var(--ink);
  margin-top: 3.5rem;
}
.stat {
  padding: 1.5rem 1rem 0.5rem;
  border-left: 1px solid var(--hairline);
}
.stat:first-child { border-left: none; }
.stat strong {
  font-family: var(--display);
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  display: block;
  line-height: 1;
}
.stat span {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--mist);
}

/* ---------- product ---------- */
.product {
  padding: clamp(4rem, 9vw, 8rem) var(--gutter);
  background: var(--ghost);
  border-block: 1px solid var(--hairline);
}
.product-inner {
  max-width: 72rem;
  margin-inline: auto;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 5rem);
  align-items: center;
}
.media-frame {
  position: relative;
  border: 1px solid var(--ink);
  background: var(--paper);
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding: 1.25rem;
}
/* plate corner marks, like a photo in a service manual */
.media-frame::before,
.media-frame::after {
  content: "";
  position: absolute;
  width: 22px; height: 22px;
  pointer-events: none;
}
.media-frame::before {
  top: 8px; left: 8px;
  border-top: 2px solid var(--ink);
  border-left: 2px solid var(--ink);
}
.media-frame::after {
  bottom: 8px; right: 8px;
  border-bottom: 2px solid var(--ink);
  border-right: 2px solid var(--ink);
}
.media-frame img { object-fit: contain; width: 100%; height: 100%; }
.price {
  display: flex; align-items: baseline; gap: 0.5rem;
  margin: 1.25rem 0 1.75rem;
}
.price #productPrice {
  font-family: var(--display);
  font-size: clamp(2.6rem, 5vw, 3.8rem);
  line-height: 1;
}
.price-note { font-family: var(--mono); font-size: 0.72rem; color: var(--mist); }
.spec-list { border-top: 1px solid var(--ink); margin-bottom: 2rem; }
.spec-list li {
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--hairline);
  font-size: 0.98rem;
}
.btn-buy { width: 100%; text-align: center; }
.detail-link { margin-top: 0.6rem; }
.buy-note {
  margin-top: 0.8rem;
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: var(--mist);
}
@media (max-width: 860px) { .product-inner { grid-template-columns: 1fr; } }

/* ---------- how (black band) ---------- */
.how {
  background: var(--ink);
  color: var(--paper);
  padding: clamp(4rem, 9vw, 8rem) var(--gutter);
}
.how-inner { max-width: 68rem; margin-inline: auto; }
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 2.5rem;
  margin-top: 3.5rem;
  counter-reset: step;
}
.steps li { border-top: 1px solid color-mix(in srgb, var(--paper) 30%, transparent); padding-top: 1.25rem; }
.step-no {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: color-mix(in srgb, var(--paper) 55%, transparent);
}
.steps h3 {
  font-family: var(--display);
  text-transform: uppercase;
  font-size: 1.5rem;
  margin: 0.75rem 0 0.6rem;
  letter-spacing: 0.02em;
}
.steps p { font-size: 0.98rem; color: color-mix(in srgb, var(--paper) 82%, transparent); }

/* ---------- promise ---------- */
.promise { padding: clamp(1rem, 2vw, 2rem) var(--gutter) clamp(4rem, 9vw, 8rem); }
.promise-inner { max-width: 56rem; margin-inline: auto; text-align: center; }
.promise-inner p { margin: 1.75rem auto 2.25rem; max-width: 40rem; font-size: 1.05rem; }

/* ---------- footer ---------- */
.site-foot {
  border-top: 1px solid var(--ink);
  padding: 2.5rem var(--gutter) 2rem;
}
.foot-top {
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 1.5rem;
}
.foot-word { font-family: var(--display); font-size: 1.6rem; }
.foot-word span { color: var(--mist); }
.foot-nav { display: flex; gap: 1.75rem; flex-wrap: wrap; }
.foot-nav a {
  font-family: var(--mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  border-bottom: 1px solid transparent;
}
.foot-nav a:hover { border-color: var(--ink); }
.foot-disclaimer {
  margin-top: 2rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--hairline);
  font-size: 0.8rem;
  color: var(--mist);
  max-width: 52rem;
}
.foot-fine {
  margin-top: 1.25rem;
  font-family: var(--mono);
  font-size: 0.68rem;
  color: var(--mist);
}

/* ---------- mobile refinements ---------- */
@media (max-width: 720px) {
  .site-head { padding: 0.8rem 1rem; gap: 0.75rem; }
  .head-cta { padding: 0.5rem 0.85rem; font-size: 0.68rem; }
  .wordmark { font-size: 1.05rem; gap: 0.4rem; }
  .wordmark .mark { width: 22px; height: 22px; }

  .hero {
    min-height: auto;
    padding: 2.25rem var(--gutter) 3rem;
    gap: 2.5rem;
  }
  .hero-title { font-size: clamp(4.2rem, 19vw, 7rem); }
  .hero-sub { font-size: 1.02rem; margin-top: 1.25rem; }
  .hero-actions { margin-top: 1.75rem; }
  .hero-actions .btn { flex: 1 1 100%; text-align: center; }

  .stage { min-height: 0; }
  .figure-tilt { width: min(100%, 330px); }

  h2 { font-size: clamp(2rem, 9vw, 3rem); }

  .marquee-track { font-size: 0.64rem; }

  .problem-grid { gap: 1.25rem; margin-top: 1.75rem; }
  .stat { padding: 1.1rem 0.75rem 0.4rem; }

  .product { padding: clamp(3rem, 8vw, 5rem) var(--gutter); }
  .price { margin: 1rem 0 1.25rem; }
  .spec-list { margin-bottom: 1.5rem; }

  .steps { gap: 1.75rem; margin-top: 2.25rem; }

  .foot-top { flex-direction: column; align-items: flex-start; }
  .foot-nav { gap: 1.25rem; }
}

/* ---------- a11y & motion ---------- */
:focus-visible { outline: 2px solid var(--ink); outline-offset: 3px; }
@media (prefers-reduced-motion: reduce) {
  .hero-title .line > span { animation: none; transform: none; }
  .marquee-track { animation: none; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .vert { transition: none; }
  html { scroll-behavior: auto; }
}