:root {
  --ink: #0b1526;
  --navy: #172a46;
  --paper: #f7f3e9;
  --gold: #d1b47b;
  --silver: #a8b3c4;
  --white: #ffffff;
  --line-dark: rgba(11, 21, 38, .26);
  --line-light: rgba(255, 255, 255, .3);
}

*, *::before, *::after { box-sizing: border-box; letter-spacing: 0; }
html, body { width: 100%; height: 100%; margin: 0; }
html { background: var(--ink); }
body { overflow: hidden; color: var(--ink); background: var(--paper); font-family: Arial, Helvetica, sans-serif; }
button, a { color: inherit; font: inherit; }
img { display: block; max-width: 100%; }
a { text-underline-offset: 4px; }
:focus-visible { outline: 3px solid var(--gold); outline-offset: 3px; box-shadow: 0 0 0 6px var(--ink); }

.skip-link {
  position: fixed;
  z-index: 200;
  top: 8px;
  left: 8px;
  padding: 12px 16px;
  color: #fff;
  background: #000;
  font-weight: 900;
  transform: translateY(-150%);
}
.skip-link:focus { transform: none; }

.reading-progress {
  position: fixed;
  z-index: 120;
  top: max(5px, env(safe-area-inset-top));
  right: clamp(14px, 3vw, 42px);
  left: clamp(14px, 3vw, 42px);
  display: grid;
  grid-template-columns: repeat(var(--moments), minmax(0, 1fr));
  gap: 6px;
  height: 17px;
  padding: 1px 4px;
  border: 1px solid rgba(255, 255, 255, .14);
  border-radius: 999px;
  background: rgba(5, 10, 18, .3);
  backdrop-filter: blur(12px);
}
.reading-progress button {
  position: relative;
  width: 100%;
  height: 15px;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
}
.reading-progress button::before,
.reading-progress button::after {
  content: "";
  position: absolute;
  top: 5px;
  right: 0;
  left: 0;
  height: 3px;
  border-radius: 99px;
}
.reading-progress button::before { background: rgba(255, 255, 255, .3); }
.reading-progress button::after {
  background: #fff;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 320ms cubic-bezier(.2, .8, .2, 1);
}
.reading-progress button.complete::after,
.reading-progress button[aria-current]::after { transform: scaleX(1); }
.reading-progress button span { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0, 0, 0, 0); }

.site-header {
  position: fixed;
  z-index: 100;
  top: max(16px, calc(env(safe-area-inset-top) + 10px));
  right: 0;
  left: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 52px;
  padding: 0 clamp(14px, 3vw, 42px);
  color: #fff;
  pointer-events: none;
}
.brand,
.header-links,
.reading-status { pointer-events: auto; }
.brand {
  display: block;
  width: 166px;
  height: 44px;
  padding: 5px 10px;
  border: 1px solid rgba(255, 255, 255, .24);
  border-radius: 999px;
  background: rgba(5, 10, 18, .34);
  backdrop-filter: blur(18px);
}
.brand img { width: 100%; height: 100%; object-fit: contain; object-position: left center; }
.reading-status {
  display: flex;
  align-items: center;
  gap: 8px;
  max-width: 220px;
  padding: 9px 13px;
  border: 1px solid rgba(255, 255, 255, .24);
  border-radius: 999px;
  background: rgba(5, 10, 18, .34);
  font-size: 9px;
  font-weight: 900;
  text-transform: uppercase;
  backdrop-filter: blur(18px);
}
.reading-status span { color: var(--gold); }
.reading-status strong { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.header-links {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 5px;
  border: 1px solid rgba(255, 255, 255, .24);
  border-radius: 999px;
  background: rgba(5, 10, 18, .34);
  backdrop-filter: blur(18px);
}
.header-links a {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 0 12px;
  border-radius: 999px;
  color: #fff;
  font-size: 9px;
  font-weight: 900;
  text-decoration: none;
  text-transform: uppercase;
}
.header-links a[aria-current="page"] { color: var(--ink); background: #fff; }

.rail {
  width: 100%;
  height: 100svh;
  overflow-x: hidden;
  overflow-y: auto;
  scroll-behavior: smooth;
  scroll-snap-type: y mandatory;
  overscroll-behavior-y: contain;
  scrollbar-width: none;
}
.rail::-webkit-scrollbar { display: none; }
.moment {
  position: relative;
  display: flex;
  width: 100%;
  min-height: 100svh;
  padding: 96px clamp(24px, 7vw, 104px) max(54px, calc(env(safe-area-inset-bottom) + 30px));
  overflow: hidden;
  scroll-snap-align: start;
  scroll-snap-stop: always;
  isolation: isolate;
}
.inner { position: relative; z-index: 2; width: min(100%, 1260px); min-width: 0; margin: auto; }
.inner > *, .hero-copy, .body-copy { min-width: 0; }
.dark { color: #fff; background: var(--ink); }
.navy { color: #fff; background: var(--navy); }
.paper { background: var(--paper); }
.silver { background: var(--silver); }
.gold { background: var(--gold); }
.eyebrow { margin: 0 0 15px; font-size: 10px; font-weight: 900; text-transform: uppercase; }
h1, h2, h3, p { letter-spacing: 0; }
h1, h2 { margin: 0; font-family: Georgia, "Times New Roman", serif; font-weight: 400; }
h1, h2, h3, p, li, td, th, a, strong, span { overflow-wrap: break-word; }
h1 { max-width: 980px; font-size: 96px; line-height: .9; }
h2 { max-width: 760px; font-size: 66px; line-height: .94; }
h3 { margin: 28px 0 9px; font-size: 20px; line-height: 1.2; }
p, li, td, th { font-size: 17px; line-height: 1.62; }
.answer { max-width: 790px; margin: 25px 0 0; font-size: 23px; line-height: 1.48; }
.lede { max-width: 700px; margin: 22px 0 0; font-size: 18px; line-height: 1.55; }
.meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin-top: 25px;
  padding-top: 16px;
  border-top: 1px solid currentColor;
  font-size: 10px;
  font-weight: 900;
  text-transform: uppercase;
}

.article-hero .inner,
.index-hero .inner {
  display: grid;
  grid-template-columns: minmax(0, .9fr) minmax(450px, 1.1fr);
  gap: clamp(44px, 8vw, 126px);
  align-items: center;
}
.hero-copy { max-width: 720px; }
.hero-visual {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 650px;
  border-right: 1px solid var(--line-light);
  border-left: 1px solid var(--line-light);
  background-image: linear-gradient(rgba(255,255,255,.09) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.09) 1px, transparent 1px);
  background-size: 32px 32px;
}
.paper .hero-visual,
.silver .hero-visual,
.gold .hero-visual { border-color: var(--line-dark); background-image: linear-gradient(rgba(11,21,38,.08) 1px, transparent 1px), linear-gradient(90deg, rgba(11,21,38,.08) 1px, transparent 1px); }
.hero-visual::before {
  content: "FIELD NOTE";
  position: absolute;
  top: 16px;
  left: 16px;
  font-size: 9px;
  font-weight: 900;
}
.hero-visual img {
  width: min(68%, 380px);
  max-height: 590px;
  object-fit: contain;
  filter: drop-shadow(0 32px 45px rgba(0, 0, 0, .3));
}
.summary-points {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0;
  margin: 28px 0 0;
  padding: 0;
  border-top: 1px solid currentColor;
  border-bottom: 1px solid currentColor;
  list-style: none;
}
.summary-points li { min-width: 0; min-height: 88px; padding: 14px 12px 12px 0; border-right: 1px solid currentColor; font-size: 12px; line-height: 1.4; overflow-wrap: anywhere; }
.summary-points li + li { padding-left: 12px; }
.summary-points li:last-child { border-right: 0; }
.summary-points strong { display: block; margin-bottom: 4px; font-size: 9px; text-transform: uppercase; }

.reading-grid {
  display: grid;
  grid-template-columns: minmax(270px, .68fr) minmax(0, 1.32fr);
  gap: clamp(42px, 8vw, 124px);
  align-items: center;
}
.section-heading { align-self: start; }
.section-heading .section-number { display: block; margin-bottom: 22px; color: var(--gold); font: 400 78px/.8 Georgia, "Times New Roman", serif; }
.body-copy { max-width: 760px; }
.body-copy > :first-child { margin-top: 0; }
.body-copy p { margin: 0 0 17px; }
.body-copy ul, .body-copy ol { margin: 18px 0 22px; padding-left: 23px; }
.body-copy li + li { margin-top: 9px; }
.body-copy a { font-weight: 800; }
.working-principle {
  margin: 26px 0;
  padding: 20px 0;
  border-top: 2px solid currentColor;
  border-bottom: 1px solid currentColor;
}
.working-principle strong { display: block; margin-bottom: 7px; font-size: 10px; text-transform: uppercase; }
.working-principle p { margin: 0; font: 400 25px/1.2 Georgia, "Times New Roman", serif; }

.comparison {
  width: 100%;
  margin: 24px 0;
  border-collapse: collapse;
  text-align: left;
}
.comparison th, .comparison td { padding: 12px 10px 12px 0; border-bottom: 1px solid currentColor; vertical-align: top; }
.comparison th { font-size: 10px; text-transform: uppercase; }
.comparison td { font-size: 14px; line-height: 1.45; }
.metric-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin: 24px 0;
  border-top: 1px solid currentColor;
  border-bottom: 1px solid currentColor;
}
.metric { min-height: 124px; padding: 18px 14px 16px 0; border-right: 1px solid currentColor; }
.metric + .metric { padding-left: 14px; }
.metric:last-child { border-right: 0; }
.metric strong { display: block; font: 400 38px/1 Georgia, "Times New Roman", serif; }
.metric span { display: block; margin-top: 8px; font-size: 10px; font-weight: 900; text-transform: uppercase; }

.faq-list { border-top: 1px solid currentColor; }
.faq-list details { border-bottom: 1px solid currentColor; }
.faq-list summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 62px;
  padding: 13px 2px;
  font-size: 16px;
  font-weight: 900;
  cursor: pointer;
  list-style: none;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; flex: 0 0 auto; font-size: 24px; font-weight: 400; }
.faq-list details[open] summary::after { content: "-"; }
.faq-list details p { max-width: 720px; margin: 0; padding: 0 36px 20px 2px; font-size: 15px; }
.references { margin-top: 22px; padding-top: 16px; border-top: 1px solid currentColor; }
.references h3 { margin-top: 0; font-size: 11px; text-transform: uppercase; }
.references a { font-size: 13px; }

.related-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); border-top: 1px solid currentColor; }
.related-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 210px;
  padding: 20px 18px 18px 0;
  border-right: 1px solid currentColor;
  border-bottom: 1px solid currentColor;
  color: inherit;
  text-decoration: none;
}
.related-card + .related-card { padding-left: 18px; }
.related-card:last-child { border-right: 0; }
.related-card span { font-size: 9px; font-weight: 900; text-transform: uppercase; }
.related-card strong { margin-top: 28px; font: 400 27px/1.08 Georgia, "Times New Roman", serif; }
.related-card b { margin-top: 18px; font-size: 16px; font-weight: 400; }

.button {
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  min-height: 50px;
  padding: 0 18px;
  border: 1px solid currentColor;
  border-radius: 999px;
  font-size: 10px;
  font-weight: 900;
  text-decoration: none;
  text-transform: uppercase;
}
.button.solid { color: var(--ink); background: #fff; border-color: #fff; }
.paper .button.solid, .silver .button.solid, .gold .button.solid { color: #fff; background: var(--ink); border-color: var(--ink); }
.actions { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 27px; }

.index-hero { background: var(--ink); color: #fff; }
.index-visual { position: relative; min-height: 650px; }
.index-phone {
  position: absolute;
  top: 50%;
  width: 230px;
  aspect-ratio: 9 / 16;
  overflow: hidden;
  border: 1px solid rgba(255,255,255,.4);
  border-radius: 28px;
  background: #080b12;
  box-shadow: 0 34px 70px rgba(0,0,0,.38);
}
.index-phone img { width: 100%; height: 100%; object-fit: cover; }
.index-phone:nth-child(1) { z-index: 1; left: 0; transform: translateY(-43%) rotate(-4deg); }
.index-phone:nth-child(2) { z-index: 3; left: 50%; width: 300px; transform: translate(-50%, -50%); }
.index-phone:nth-child(3) { z-index: 2; right: 0; transform: translateY(-57%) rotate(4deg); }
.topic-layout {
  display: grid;
  grid-template-columns: minmax(250px, .58fr) minmax(0, 1.42fr);
  gap: clamp(42px, 8vw, 120px);
  align-items: center;
}
.article-list { border-top: 1px solid currentColor; }
.article-link {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr) auto;
  gap: 15px;
  align-items: center;
  min-height: 78px;
  border-bottom: 1px solid currentColor;
  color: inherit;
  text-decoration: none;
}
.article-link span { font-size: 9px; font-weight: 900; }
.article-link strong { font: 400 25px/1.1 Georgia, "Times New Roman", serif; }
.article-link em { font-size: 9px; font-style: normal; font-weight: 900; text-transform: uppercase; }
.feature-note {
  display: grid;
  grid-template-columns: minmax(0, .85fr) minmax(280px, 1.15fr);
  gap: clamp(38px, 7vw, 100px);
  align-items: center;
}
.feature-image { position: relative; display: grid; place-items: center; min-height: 620px; border: 1px solid currentColor; }
.feature-image img { width: min(58%, 340px); max-height: 560px; object-fit: contain; filter: drop-shadow(0 28px 36px rgba(0,0,0,.28)); }
.feature-copy h2 { font-size: 72px; }
.feature-copy .answer { font-size: 20px; }

.site-footer { margin-top: 28px; padding-top: 16px; border-top: 1px solid currentColor; font-size: 10px; font-weight: 900; text-transform: uppercase; }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 18px; margin-top: 12px; }
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 480ms ease, transform 680ms cubic-bezier(.2,.8,.2,1); }
.moment.active .reveal { opacity: 1; transform: none; }

@media (max-width: 1050px) {
  h1 { font-size: 76px; }
  h2 { font-size: 56px; }
  .article-hero .inner, .index-hero .inner { grid-template-columns: minmax(0, .9fr) minmax(380px, 1.1fr); gap: 38px; }
  .hero-visual, .index-visual { min-height: 570px; }
  .index-phone { width: 180px; }
  .index-phone:nth-child(2) { width: 240px; }
}

@media (max-width: 760px) {
  .reading-progress { right: 12px; left: 12px; gap: 4px; }
  .reading-progress button::before, .reading-progress button::after { height: 2px; }
  .site-header { top: max(14px, calc(env(safe-area-inset-top) + 8px)); padding-inline: 12px; }
  .brand { width: 108px; height: 40px; padding-inline: 8px; }
  .reading-status { flex: 0 1 116px; max-width: 116px; padding: 8px 9px; font-size: 8px; }
  .reading-status strong { max-width: 74px; }
  .header-links { gap: 0; padding: 3px; }
  .header-links a { min-height: 34px; padding-inline: 9px; font-size: 8px; }
  .header-links a + a { display: none; }
  .moment { min-height: 100svh; padding: 72px 16px max(34px, calc(env(safe-area-inset-bottom) + 24px)); overflow: visible; }
  h1 { font-size: 48px; }
  h2 { font-size: 40px; }
  h3 { margin-top: 20px; font-size: 18px; }
  p, li, td, th { font-size: 15px; line-height: 1.5; }
  .answer { margin-top: 15px; font-size: 17px; line-height: 1.42; }
  .lede { margin-top: 14px; font-size: 15px; }
  .meta { gap: 6px 14px; margin-top: 15px; padding-top: 11px; font-size: 8px; }
  .article-hero .inner, .index-hero .inner { display: grid; grid-template-columns: 1fr; grid-template-rows: minmax(270px, .95fr) auto; gap: 13px; }
  .article-hero .hero-copy, .index-hero .hero-copy { width: 100%; max-width: 100%; }
  .article-hero .hero-visual, .index-hero .index-visual { grid-row: 1; }
  .article-hero .hero-copy, .index-hero .hero-copy { grid-row: 2; }
  .hero-visual, .index-visual { min-height: 0; height: 100%; border: 1px solid var(--line-light); }
  .hero-visual img { width: min(43%, 164px); max-height: 260px; }
  .summary-points { margin-top: 14px; }
  .summary-points li { min-height: 60px; padding: 8px 7px 7px 0; font-size: 9px; }
  .summary-points li + li { padding-left: 7px; }
  .summary-points strong { font-size: 7px; }
  .reading-grid, .topic-layout, .feature-note { grid-template-columns: 1fr; gap: 22px; align-items: start; }
  .section-heading .section-number { margin-bottom: 11px; font-size: 52px; }
  .body-copy { max-width: none; }
  .working-principle { margin: 18px 0; padding: 15px 0; }
  .working-principle p { font-size: 20px; }
  .comparison { display: block; overflow-x: auto; }
  .comparison th, .comparison td { min-width: 130px; font-size: 12px; }
  .metric { min-height: 94px; padding-top: 13px; }
  .metric strong { font-size: 29px; }
  .metric span { font-size: 8px; }
  .faq-list summary { min-height: 56px; font-size: 14px; }
  .faq-list details p { font-size: 14px; }
  .related-grid { grid-template-columns: 1fr; }
  .related-card, .related-card + .related-card { min-height: 92px; padding: 14px 2px; border-right: 0; }
  .related-card strong { margin-top: 10px; font-size: 21px; }
  .related-card b { margin-top: 8px; }
  .index-phone { width: min(31vw, 118px); border-radius: 18px; }
  .index-phone:nth-child(2) { width: min(42vw, 162px); }
  .feature-note { height: 100%; }
  .feature-image { min-height: 280px; }
  .feature-image img { width: min(42%, 162px); max-height: 260px; }
  .feature-copy h2 { font-size: 40px; }
  .feature-copy .answer { font-size: 16px; }
  .article-link { grid-template-columns: 26px minmax(0,1fr) auto; gap: 9px; min-height: 64px; }
  .article-link strong { font-size: 19px; }
  .article-link em { font-size: 7px; }
}

@media (max-width: 390px) {
  .reading-status { flex-basis: 100px; max-width: 100px; gap: 5px; padding-inline: 7px; font-size: 7px; }
  .reading-status strong { max-width: 64px; }
  .brand { width: 101px; }
  .header-links a { padding-inline: 8px; }
}

@media (max-width: 350px), (max-height: 700px) {
  .moment { padding-top: 68px; padding-bottom: 28px; }
  h1 { font-size: 41px; }
  h2, .feature-copy h2 { font-size: 35px; }
  .answer { font-size: 15px; }
  .article-hero .inner, .index-hero .inner { grid-template-rows: minmax(215px, .78fr) auto; }
  .hero-visual img { width: min(35%, 132px); max-height: 205px; }
  .summary-points li { font-size: 8px; }
  .reading-status { flex-basis: 92px; max-width: 92px; }
  .reading-status strong { max-width: 57px; }
  .header-links a { padding-inline: 7px; }
}

@media (prefers-reduced-motion: reduce) {
  .rail { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .reading-progress button::after { transition: none; }
}

@media (forced-colors: active) {
  .moment, .site-header, .reading-progress, .brand, .reading-status, .header-links { color: CanvasText; background: Canvas; border-color: CanvasText; }
  .reading-progress button { border: 1px solid CanvasText; }
  .reading-progress button[aria-current] { background: Highlight; }
}

@media print {
  html, body { height: auto; overflow: visible; background: #fff; }
  .reading-progress, .site-header { display: none; }
  .rail { height: auto; overflow: visible; }
  .moment { min-height: 0; padding: 36px 0; break-inside: avoid; }
  .reveal { opacity: 1; transform: none; }
}