:root {
  --ink: #17202f;
  --ink-soft: #263247;
  --paper: #fffaf0;
  --surface: #ffffff;
  --muted: #687383;
  --line: rgba(23, 32, 47, 0.14);
  --gold: #c8913a;
  --coral: #df6f5a;
  --teal: #3c8b8b;
  --sky: #8eb8d8;
  --shadow: 0 22px 58px rgba(23, 32, 47, 0.16);
  --radius: 8px;
  --module-radius: 18px;
  --content: min(1160px, calc(100% - 44px));
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 18px 18px, rgba(200, 145, 58, 0.12) 1px, transparent 1.5px),
    linear-gradient(90deg, rgba(23, 32, 47, 0.035) 1px, transparent 1px),
    linear-gradient(180deg, #fffaf0 0%, #f4efe6 52%, #ffffff 100%);
  background-size: 36px 36px, 34px 34px, auto;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", Arial, sans-serif;
  line-height: 1.72;
  text-rendering: optimizeLegibility;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
  text-decoration: none;
}

p,
figure {
  margin: 0;
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.2;
}

h1 {
  font-size: clamp(2.25rem, 5vw, 4.55rem);
  font-weight: 900;
  color: var(--gold);
  background: linear-gradient(90deg, var(--gold), var(--coral));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.stage h1 {
  position: relative;
  display: inline-block;
}

.stage h1::after {
  content: "";
  position: absolute;
  left: 0;
  right: 10%;
  bottom: 0.08em;
  z-index: -1;
  height: 0.22em;
  background: rgba(223, 111, 90, 0.24);
  border-radius: 999px;
}

h2 {
  position: relative;
  display: inline;
  font-size: clamp(1.35rem, 2.35vw, 2.2rem);
  font-weight: 880;
  color: var(--teal);
  box-shadow: inset 0 -0.28em rgba(200, 145, 58, 0.18);
}

h3 {
  font-size: 1.08rem;
}

.skip-link {
  position: fixed;
  left: 18px;
  top: -60px;
  z-index: 1000;
  padding: 10px 16px;
  border-radius: var(--radius);
  background: var(--ink);
  color: #fff;
  transition: top 0.18s ease;
}

.skip-link:focus {
  top: 18px;
}

.side-rail {
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 80;
  width: 248px;
  display: flex;
  flex-direction: column;
  padding: 28px 22px;
  color: #fff;
  background:
    linear-gradient(180deg, rgba(200, 145, 58, 0.12), transparent 34%),
    repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.035) 0 1px, transparent 1px 12px),
    var(--ink);
  border-right: 1px solid rgba(255, 255, 255, 0.12);
}

.rail-brand {
  display: grid;
  grid-template-columns: 54px 1fr;
  gap: 13px;
  align-items: center;
  padding-bottom: 24px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  font-size: 1.28rem;
  font-weight: 900;
}

.rail-brand img {
  width: 54px;
  height: 72px;
  object-fit: cover;
  border-radius: 6px;
  border: 2px solid rgba(255, 255, 255, 0.18);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.28);
}

.rail-nav {
  display: grid;
  gap: 8px;
  margin-top: 26px;
}

.rail-nav a {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 8px 14px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  color: rgba(255, 255, 255, 0.76);
  font-weight: 700;
  transition: color 0.2s ease, background 0.2s ease, transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.rail-nav a::before {
  content: "";
  position: absolute;
  left: 8px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--gold);
  opacity: 0.55;
}

.rail-nav a::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 4.7em;
  height: 4.7em;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(200, 145, 58, 0.34) 0%, rgba(200, 145, 58, 0.14) 55%, rgba(200, 145, 58, 0) 72%);
  transform: translate(-50%, -50%) scale(0.72);
  opacity: 0;
  transition: opacity 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
  pointer-events: none;
  z-index: 0;
}

.rail-nav a span {
  position: relative;
  z-index: 1;
}

.rail-nav a:hover,
.rail-nav a:focus-visible,
.rail-nav a.is-current {
  color: #fff;
  text-shadow: 0 0 10px rgba(255, 255, 255, 0.32);
  border-color: rgba(200, 145, 58, 0.72);
  background: rgba(200, 145, 58, 0.08);
  box-shadow:
    0 0 0 1px rgba(255, 255, 255, 0.08) inset,
    0 10px 24px rgba(200, 145, 58, 0.18);
  transform: translateX(4px);
}

.rail-nav a:hover::before,
.rail-nav a:focus-visible::before,
.rail-nav a.is-current::before {
  opacity: 1;
  box-shadow: 0 0 12px rgba(200, 145, 58, 0.8);
}

.rail-nav a:hover::after,
.rail-nav a:focus-visible::after,
.rail-nav a.is-current::after {
  opacity: 1;
  transform: translate(-50%, -50%) scale(1);
}

.rail-download {
  margin-top: auto;
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  background:
    radial-gradient(circle at 30% 28%, rgba(255, 255, 255, 0.34) 0%, rgba(255, 255, 255, 0) 38%),
    linear-gradient(135deg, #d6a248, var(--gold));
  color: var(--ink);
  font-weight: 900;
  box-shadow: 0 18px 34px rgba(0, 0, 0, 0.24);
  transition: transform 0.2s ease, box-shadow 0.2s ease, filter 0.2s ease;
}

.rail-download:hover,
.rail-download:focus-visible {
  transform: translateY(-3px);
  filter: saturate(1.08);
  box-shadow: 0 22px 42px rgba(0, 0, 0, 0.32);
}

.mobile-header {
  display: none;
}

.page-shell {
  margin-left: 248px;
}

.stage {
  position: relative;
  min-height: 100vh;
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(360px, 0.55fr);
  grid-template-rows: minmax(0, 1fr) auto;
  gap: 0;
  overflow: hidden;
  background: #fff4dc;
  color: var(--ink);
  border-radius: 0 0 var(--module-radius) var(--module-radius);
}

.stage::before {
  content: "";
  position: absolute;
  inset: 22px;
  z-index: 1;
  pointer-events: none;
  border: 1px solid rgba(200, 145, 58, 0.28);
  border-radius: var(--module-radius);
}

.stage::after {
  content: "";
  position: absolute;
  right: 36px;
  top: 36px;
  z-index: 1;
  width: 92px;
  height: 92px;
  pointer-events: none;
  border-top: 4px solid rgba(60, 139, 139, 0.46);
  border-right: 4px solid rgba(200, 145, 58, 0.46);
  border-radius: 0 var(--module-radius) 0 0;
}

.stage-media {
  position: relative;
  z-index: 2;
  min-height: 680px;
  isolation: isolate;
}

.stage-media::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(255, 244, 220, 0.08), rgba(255, 244, 220, 0.78)),
    linear-gradient(180deg, rgba(255, 250, 240, 0.02), rgba(255, 244, 220, 0.34));
}

.stage-media img {
  width: 100%;
  height: 100%;
  min-height: inherit;
  object-fit: cover;
}

.stage-copy {
  position: relative;
  z-index: 2;
  align-self: center;
  padding: 96px min(7vw, 90px) 56px 46px;
  background:
    linear-gradient(90deg, rgba(200, 145, 58, 0.16) 0 5px, transparent 5px),
    linear-gradient(180deg, rgba(255, 250, 240, 0.94), rgba(255, 244, 220, 0.88));
  border-left: 1px solid rgba(23, 32, 47, 0.1);
  border-radius: var(--module-radius) 0 0 var(--module-radius);
}

.label {
  display: flex;
  width: fit-content;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
  color: var(--gold);
  font-size: 0.88rem;
  font-weight: 900;
}

.label::before {
  content: "";
  width: 34px;
  height: 2px;
  background: currentColor;
}

.stage .lead {
  max-width: 620px;
  margin-top: 22px;
  color: var(--ink-soft);
  font-size: clamp(1.05rem, 1.5vw, 1.24rem);
}

.stage-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.button {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 12px 24px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-weight: 900;
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

.button::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(110deg, transparent 0%, rgba(255, 255, 255, 0.42) 44%, transparent 70%);
  transform: translateX(-120%);
  transition: transform 0.48s ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-3px);
}

.button:hover::after,
.button:focus-visible::after {
  transform: translateX(120%);
}

.button-primary {
  color: var(--ink);
  background: var(--gold);
  box-shadow: 0 18px 38px rgba(200, 145, 58, 0.28);
}

.button-muted {
  color: var(--ink);
  border-color: rgba(23, 32, 47, 0.18);
  background: rgba(255, 255, 255, 0.62);
}

.stage-notes {
  position: relative;
  z-index: 2;
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid rgba(23, 32, 47, 0.12);
  background: rgba(255, 250, 240, 0.94);
  border-radius: 0 0 var(--module-radius) var(--module-radius);
  overflow: hidden;
}

.stage-notes article {
  padding: 22px 32px;
  border-right: 1px solid rgba(23, 32, 47, 0.1);
}

.stage-notes span {
  display: block;
  color: var(--muted);
  font-size: 0.86rem;
}

.stage-notes strong {
  display: block;
  margin-top: 4px;
  color: var(--ink);
}

.metric-strip,
.feature-story,
.content-deck,
.guide-board,
.split-panel,
.log-section,
.install-section,
.faq-section,
.friend-links,
.site-footer {
  width: var(--content);
  margin: 0 auto;
}

.metric-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  padding: 46px 0 24px;
}

.metric-strip article {
  position: relative;
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--module-radius);
  overflow: hidden;
  box-shadow: 0 12px 28px rgba(23, 32, 47, 0.06);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
}

.metric-strip article::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 5px;
  background: var(--teal);
}

.metric-strip article:nth-child(2)::before {
  background: var(--gold);
}

.metric-strip article:nth-child(3)::before {
  background: var(--coral);
}

.metric-strip article:nth-child(4)::before {
  background: var(--sky);
}

.metric-strip article:hover {
  transform: translateY(-4px);
  border-color: rgba(60, 139, 139, 0.3);
  box-shadow: 0 20px 42px rgba(23, 32, 47, 0.12);
}

.metric-strip strong {
  display: block;
  margin-bottom: 7px;
  font-size: 1.28rem;
}

.metric-strip span {
  color: var(--muted);
  font-size: 0.95rem;
}

.feature-story,
.content-deck,
.guide-board,
.split-panel,
.log-section,
.install-section,
.faq-section {
  position: relative;
  padding: 78px 0;
}

.feature-story::before,
.content-deck::before,
.guide-board::before,
.split-panel::before,
.log-section::before,
.install-section::before,
.faq-section::before {
  content: "";
  position: absolute;
  left: 0;
  top: 44px;
  width: 74px;
  height: 10px;
  border-top: 2px solid rgba(200, 145, 58, 0.42);
  border-bottom: 2px solid rgba(60, 139, 139, 0.26);
  pointer-events: none;
}

.feature-story {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(360px, 0.72fr);
  gap: 46px;
  align-items: end;
}

.story-text {
  position: relative;
  padding: 34px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--module-radius);
  box-shadow: var(--shadow);
}

.story-text::before,
.deck-grid article::before,
.log-grid article::before,
.download-box::before,
.faq-list details::before {
  content: "";
  position: absolute;
  left: 18px;
  right: 18px;
  top: 0;
  height: 4px;
  border-radius: 0 0 999px 999px;
  background: linear-gradient(90deg, var(--gold), var(--teal));
}

.story-text h2,
.section-intro h2,
.split-panel h2,
.install-copy h2 {
  margin-bottom: 18px;
}

.story-text p:not(.label),
.section-intro p:not(.label),
.split-panel p,
.install-copy li,
.download-box p,
.faq-list p,
.site-footer p {
  color: var(--muted);
}

.story-text p + p {
  margin-top: 14px;
}

.story-image,
.wide-shot,
.split-panel figure {
  position: relative;
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--module-radius);
  box-shadow: var(--shadow);
}

.story-image::after,
.wide-shot::after,
.split-panel figure::after {
  content: "";
  position: absolute;
  inset: 10px;
  border: 1px solid rgba(255, 255, 255, 0.66);
  border-radius: calc(var(--module-radius) - 6px);
  pointer-events: none;
}

.story-image img,
.wide-shot img,
.split-panel figure img,
.guide-list img {
  width: 100%;
  object-fit: cover;
  transition: transform 0.45s ease, filter 0.3s ease;
}

.story-image:hover img,
.wide-shot:hover img,
.split-panel figure:hover img,
.guide-list article:hover img {
  transform: scale(1.035);
  filter: saturate(1.06) contrast(1.02);
}

.story-image img {
  aspect-ratio: 4 / 3;
}

figcaption {
  padding: 13px 16px;
  color: var(--muted);
  font-size: 0.92rem;
}

.section-intro {
  position: relative;
  max-width: 820px;
  margin: 0 auto 34px;
  text-align: center;
}

.section-intro .label {
  margin-left: auto;
  margin-right: auto;
}

.section-intro::after {
  content: "";
  display: block;
  width: 112px;
  height: 3px;
  margin: 20px auto 0;
  background: linear-gradient(90deg, transparent, var(--coral), var(--gold), transparent);
  border-radius: 999px;
}

.section-intro.align-left {
  margin-left: 0;
  text-align: left;
}

.deck-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.wide-shot {
  grid-column: span 2;
  grid-row: span 2;
}

.wide-shot img {
  height: 100%;
  min-height: 390px;
}

.deck-grid article,
.log-grid article,
.faq-list details,
.download-box {
  position: relative;
  padding: 24px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--module-radius);
  box-shadow: 0 14px 30px rgba(23, 32, 47, 0.07);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
}

.deck-grid article:hover,
.log-grid article:hover,
.download-box:hover,
.faq-list details:hover {
  transform: translateY(-4px);
  border-color: rgba(200, 145, 58, 0.34);
  box-shadow: 0 22px 44px rgba(23, 32, 47, 0.12);
}

.deck-grid h3,
.log-grid h3,
.guide-list h3,
.download-box h3 {
  margin-bottom: 9px;
}

.deck-grid p,
.log-grid p,
.guide-list p {
  color: var(--muted);
}

.guide-list {
  display: grid;
  gap: 18px;
}

.guide-list article {
  position: relative;
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  gap: 24px;
  align-items: center;
  padding: 18px;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid var(--line);
  border-radius: var(--module-radius);
  overflow: hidden;
  box-shadow: 0 14px 30px rgba(23, 32, 47, 0.08);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
}

.guide-list article::after {
  content: "";
  position: absolute;
  right: 22px;
  bottom: 18px;
  width: 46px;
  height: 46px;
  border-right: 3px solid rgba(223, 111, 90, 0.24);
  border-bottom: 3px solid rgba(200, 145, 58, 0.28);
  border-radius: 0 0 var(--radius) 0;
}

.guide-list article:hover {
  transform: translateX(5px);
  border-color: rgba(60, 139, 139, 0.28);
  box-shadow: 0 20px 42px rgba(23, 32, 47, 0.12);
}

.guide-list img {
  height: 180px;
  border-radius: calc(var(--module-radius) - 4px);
}

.guide-list span,
.log-grid span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 42px;
  height: 28px;
  margin-bottom: 11px;
  background: rgba(60, 139, 139, 0.12);
  color: var(--teal);
  font-weight: 900;
  font-size: 0.86rem;
}

.split-panel {
  display: grid;
  grid-template-columns: minmax(340px, 0.76fr) minmax(0, 1fr);
  gap: 42px;
  align-items: center;
}

.split-panel figure img {
  aspect-ratio: 4 / 3;
}

.feature-points {
  display: grid;
  gap: 12px;
  padding: 0;
  margin: 22px 0 0;
  list-style: none;
}

.feature-points li {
  position: relative;
  padding: 16px 18px;
  background: rgba(255, 255, 255, 0.76);
  border-left: 4px solid var(--coral);
  border-radius: var(--module-radius);
  color: var(--muted);
  box-shadow: 0 10px 24px rgba(23, 32, 47, 0.06);
  transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.feature-points li:hover {
  transform: translateX(5px);
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 16px 32px rgba(23, 32, 47, 0.1);
}

.feature-points strong {
  color: var(--ink);
}

.log-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.install-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 330px;
  gap: 30px;
  align-items: stretch;
}

.install-copy {
  position: relative;
  padding: 34px;
  background:
    repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.045) 0 1px, transparent 1px 14px),
    var(--ink);
  color: #fff;
  border-radius: var(--module-radius);
  overflow: hidden;
}

.install-copy::after {
  content: "";
  position: absolute;
  right: 24px;
  top: 24px;
  width: 82px;
  height: 82px;
  border-top: 4px solid rgba(200, 145, 58, 0.48);
  border-right: 4px solid rgba(223, 111, 90, 0.35);
  border-radius: 0 var(--module-radius) 0 0;
  pointer-events: none;
}

.install-copy .label,
.install-copy li {
  color: rgba(255, 255, 255, 0.78);
}

.steps {
  display: grid;
  gap: 12px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: step;
}

.steps li {
  counter-increment: step;
  position: relative;
  padding: 14px 16px 14px 54px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--module-radius);
  transition: background 0.2s ease, transform 0.2s ease;
}

.steps li:hover {
  background: rgba(255, 255, 255, 0.15);
  transform: translateX(4px);
}

.steps li::before {
  content: counter(step);
  position: absolute;
  left: 16px;
  top: 14px;
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  background: var(--gold);
  color: var(--ink);
  font-weight: 900;
  border-radius: 50%;
}

.download-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}

.download-box img {
  width: min(188px, 70%);
  margin-bottom: 18px;
  border-radius: 6px;
  border: 6px solid #fff;
  box-shadow: 0 14px 30px rgba(23, 32, 47, 0.16);
}

.download-box .button {
  margin-top: 14px;
}

.faq-list {
  display: grid;
  gap: 12px;
  max-width: 980px;
  margin: 0 auto;
}

.faq-list details {
  padding: 0;
}

.faq-list summary {
  cursor: pointer;
  padding: 20px 58px 20px 22px;
  position: relative;
  font-weight: 900;
  list-style: none;
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list summary::after {
  content: "+";
  position: absolute;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--coral);
  font-size: 1.4rem;
}

.faq-list details[open] summary::after {
  content: "-";
}

.faq-list details[open] {
  border-color: rgba(60, 139, 139, 0.32);
  background: linear-gradient(180deg, #fff, rgba(255, 244, 220, 0.5));
}

.faq-list p {
  padding: 0 58px 22px 22px;
}

.friend-links {
  padding: 46px 0;
  text-align: center;
  border-top: 1px solid rgba(23, 32, 47, 0.08);
  border-bottom: 1px solid rgba(23, 32, 47, 0.08);
}

.friend-links h2 {
  margin-bottom: 18px;
}

.friend-links div {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}

.friend-links a,
.site-footer a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 9px 18px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  font-weight: 800;
  box-shadow: 0 10px 24px rgba(23, 32, 47, 0.06);
  transition: transform 0.2s ease, color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.friend-links a:hover,
.site-footer a:hover,
.friend-links a:focus-visible,
.site-footer a:focus-visible {
  transform: translateY(-3px);
  color: var(--teal);
  border-color: rgba(60, 139, 139, 0.34);
  box-shadow: 0 16px 32px rgba(23, 32, 47, 0.1);
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 32px 0 46px;
  border-top: 1px solid var(--line);
}

.site-footer p {
  margin-top: 4px;
}

.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}

@media (max-width: 1120px) {
  .side-rail {
    top: 66px;
    bottom: 0;
    height: calc(100vh - 66px);
    padding-top: 22px;
    overflow-y: auto;
    transform: translateX(-100%);
    transition: transform 0.24s ease;
  }

  .side-rail.is-open {
    transform: translateX(0);
  }

  .mobile-header {
    position: fixed;
    inset: 0 0 auto;
    z-index: 90;
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 66px;
    padding: 8px 18px;
    color: #fff;
    background: rgba(23, 32, 47, 0.94);
    backdrop-filter: blur(14px);
  }

  .mobile-brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 900;
  }

  .mobile-brand img {
    width: 36px;
    height: 48px;
    object-fit: cover;
    border-radius: 5px;
  }

  .menu-button {
    width: 42px;
    height: 42px;
    border: 1px solid rgba(255, 255, 255, 0.22);
    border-radius: var(--radius);
    background: transparent;
    padding: 9px;
  }

  .menu-button span {
    display: block;
    height: 2px;
    margin: 5px 0;
    background: #fff;
    transition: transform 0.2s ease, opacity 0.2s ease;
  }

  .menu-button[aria-expanded="true"] span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .menu-button[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
  }

  .menu-button[aria-expanded="true"] span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .page-shell {
    margin-left: 0;
  }

  .stage {
    padding-top: 66px;
  }
}

@media (max-width: 920px) {
  .stage,
  .feature-story,
  .split-panel,
  .install-section,
  .guide-list article {
    grid-template-columns: 1fr;
  }

  .stage-media {
    min-height: 420px;
  }

  .stage-copy {
    padding: 40px 24px;
  }

  .stage-notes,
  .metric-strip,
  .deck-grid,
  .log-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .wide-shot {
    grid-column: span 2;
  }

  .guide-list img {
    height: 260px;
  }
}

@media (max-width: 640px) {
  :root {
    --content: min(100% - 28px, 1160px);
  }

  .side-rail {
    width: min(84vw, 286px);
  }

  .stage-notes,
  .metric-strip,
  .deck-grid,
  .log-grid {
    grid-template-columns: 1fr;
  }

  .wide-shot {
    grid-column: span 1;
  }

  .wide-shot img {
    min-height: 260px;
  }

  .stage-actions .button {
    width: 100%;
  }

  .feature-story,
  .content-deck,
  .guide-board,
  .split-panel,
  .log-section,
  .install-section,
  .faq-section {
    padding: 56px 0;
  }

  .story-text,
  .install-copy,
  .deck-grid article,
  .log-grid article,
  .download-box {
    padding: 22px;
  }

  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }
}