/* Hallmark · macrostructure: Photographic · theme: Midnight Plum · tone: cinematic restraint · anchor hue: magenta · pre-emit critique: P5 H5 E5 S5 R5 V5 · contrast: pass (40–41) · nav: N6 · footer: Ft6 · slop: pass (42–45) · honest: pass (46) · chrome: pass (47) · tokens: pass (48) · responsive: pass (49) · icons: pass (30) · mobile: pass (34, 49, 50–57) */
@import url("../../tokens.css");

* { box-sizing: border-box; }
html { overflow-x: clip; scroll-behavior: smooth; background: var(--color-paper); }
body { margin: 0; overflow-x: clip; background: var(--color-paper); color: var(--color-ink); font-family: var(--font-body); font-size: var(--text-base); line-height: 1.6; }
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; }
:focus-visible { outline: 2px solid var(--color-focus); outline-offset: 3px; }
.skip-link { position: fixed; left: var(--space-md); top: var(--space-md); z-index: 500; padding: var(--space-sm) var(--space-md); background: var(--color-accent); color: var(--color-accent-ink); transform: translateY(-150%); transition: transform var(--dur-short) var(--ease-out); }
.skip-link:focus { transform: translateY(0); }
.site-shell { width: min(100% - (var(--space-lg) * 2), 1180px); margin-inline: auto; }
.site-header { position: fixed; inset: var(--space-md) var(--space-md) auto; z-index: var(--z-sticky-nav); }
.site-nav { min-height: var(--nav-height); display: flex; align-items: center; gap: var(--space-md); padding: var(--space-xs) var(--space-sm) var(--space-xs) var(--space-md); background: color-mix(in oklab, var(--color-paper) 88%, transparent); border: 1px solid var(--color-line); backdrop-filter: blur(16px); }
.site-mark { min-width: 0; display: inline-flex; align-items: center; gap: var(--space-sm); font-family: var(--font-display); font-weight: 800; line-height: 1; white-space: nowrap; }
.site-mark img { width: 42px; height: 28px; object-fit: cover; object-position: 50% 50%; }
.site-menu { display: flex; align-items: center; gap: var(--space-md); margin: 0 auto 0 0; padding: 0; list-style: none; }
.site-menu a, .nav-toggle { color: var(--color-muted); font-size: var(--text-sm); white-space: nowrap; }
.site-menu a { transition: color var(--dur-short) var(--ease-out); }
.site-menu a:hover, .site-menu a[aria-current="page"] { color: var(--color-ink); }
.nav-toggle { display: none; border: 0; background: transparent; cursor: pointer; }
.button { min-height: 44px; display: inline-flex; align-items: center; justify-content: center; gap: var(--space-sm); padding: 0 var(--space-lg); border: 1px solid transparent; font-size: var(--text-sm); font-weight: 700; line-height: 1; white-space: nowrap; cursor: pointer; transition: transform var(--dur-short) var(--ease-out), background-color var(--dur-short) var(--ease-out), color var(--dur-short) var(--ease-out), border-color var(--dur-short) var(--ease-out); }
.button:hover { transform: translateY(-2px); }
.button:active { transform: translateY(1px); }
.button:disabled, .button[aria-disabled="true"] { opacity: .55; cursor: not-allowed; }
.button--accent { position: relative; overflow: hidden; background: var(--color-accent); color: var(--color-accent-ink); }
.button--accent::after { content: ""; position: absolute; inset: 0 auto 0 -45%; width: 28%; background: var(--color-sheen); transform: skewX(-18deg); animation: shimmer 4s var(--ease-in-out) infinite; }
.button--quiet { border-color: var(--color-line-strong); color: var(--color-ink); }
.button--quiet:hover { border-color: var(--color-accent); color: var(--color-accent); }
.eyebrow { margin: 0 0 var(--space-sm); color: var(--color-accent); font-family: var(--font-outlier); font-size: var(--text-xs); font-weight: 700; letter-spacing: .14em; line-height: 1; text-transform: uppercase; }
.hero-fold { position: relative; min-height: 720px; display: grid; align-items: end; overflow: hidden; background: var(--color-paper-3); }
.hero-image { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: center; }
.hero-shade { position: absolute; inset: 0; background: linear-gradient(90deg, color-mix(in oklab, var(--color-paper) 92%, transparent), color-mix(in oklab, var(--color-paper) 26%, transparent) 65%, color-mix(in oklab, var(--color-paper) 18%, transparent)); }
.hero-copy { position: relative; z-index: 1; padding: 0 0 var(--space-3xl); margin-top: auto; }
.hero-copy .eyebrow { color: var(--color-ink); }
.hero-copy h1 { max-width: 720px; margin: 0; color: var(--color-ink); font-family: var(--font-display); font-size: clamp(2.8rem, 7vw, 6.2rem); font-weight: 800; letter-spacing: -.055em; line-height: 1.03; overflow-wrap: anywhere; }
.hero-copy h1 small { display: block; margin-top: var(--space-sm); color: var(--color-ink-soft); font-family: var(--font-body); font-size: clamp(var(--text-sm), 1.8vw, var(--text-md)); font-weight: 500; letter-spacing: .02em; line-height: 1.35; }
.hero-lede { max-width: 58ch; margin: var(--space-lg) 0 0; color: var(--color-ink-soft); font-size: clamp(var(--text-base), 2vw, var(--text-md)); }
.hero-actions { display: flex; align-items: center; flex-wrap: wrap; gap: var(--space-sm); margin-top: var(--space-lg); }
.hero-meta { display: flex; align-items: center; flex-wrap: wrap; gap: var(--space-sm) var(--space-lg); margin-top: var(--space-lg); color: var(--color-ink-soft); font-family: var(--font-outlier); font-size: var(--text-xs); letter-spacing: .08em; text-transform: uppercase; }
.hero-annotation { position: absolute; top: 118px; right: var(--space-lg); z-index: 1; display: grid; gap: var(--space-xs); color: var(--color-ink-soft); font-family: var(--font-outlier); font-size: var(--text-xs); letter-spacing: .1em; text-align: right; }
.fact-ribbon { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 0; padding-block: var(--space-lg); border-bottom: 1px solid var(--color-line); }
.fact-ribbon > div { display: grid; gap: var(--space-xs); min-width: 0; padding: var(--space-xs) var(--space-lg); border-left: 1px solid var(--color-line); }
.fact-ribbon > div:first-child { padding-left: 0; border-left: 0; }
.fact-ribbon span { color: var(--color-muted); font-size: var(--text-xs); }
.fact-ribbon strong { font-family: var(--font-display); font-size: var(--text-md); line-height: 1.15; overflow-wrap: anywhere; }
.photo-band { position: relative; margin-top: var(--space-4xl); }
.photo-band img { width: 100%; max-height: 720px; object-fit: cover; object-position: center; }
.photo-caption { position: absolute; right: var(--space-lg); bottom: var(--space-lg); max-width: 18ch; margin: 0; color: var(--color-ink); font-family: var(--font-display); font-size: clamp(var(--text-md), 2.7vw, var(--text-xl)); font-weight: 700; line-height: 1.1; text-align: right; }
.reading-section, .feature-section, .gallery-section, .timeline-section, .fit-section, .faq-section, .platform-section, .requirements-section, .guide-index-section, .guide-body, .article-rail, .article-index { padding-block: var(--space-4xl); }
.reading-section { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: var(--space-4xl); }
.reading-head h2, .section-intro h2, .download-band h2, .final-band h2, .page-lead h1, .article-hero h1 { max-width: 15ch; margin: 0; font-family: var(--font-display); font-size: clamp(2rem, 5vw, 4.6rem); font-weight: 800; letter-spacing: -.045em; line-height: 1.04; overflow-wrap: anywhere; }
.reading-copy { max-width: 65ch; font-size: var(--text-md); }
.reading-copy p { margin: 0 0 var(--space-lg); }
.content-note { padding-top: var(--space-lg); border-top: 1px solid var(--color-line); color: var(--color-muted); font-size: var(--text-sm); }
.section-intro { max-width: 70ch; margin-bottom: var(--space-2xl); }
.section-intro > p:last-child { max-width: 60ch; margin: var(--space-md) 0 0; color: var(--color-muted); }
.feature-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-xl) var(--space-lg); }
.feature-card { min-width: 0; padding-top: var(--space-md); border-top: 1px solid var(--color-line-strong); transition: transform var(--dur-mid) var(--ease-out), box-shadow var(--dur-mid) var(--ease-out); }
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 16px 32px color-mix(in oklab, var(--color-ink) 10%, transparent); }
.feature-code, .fit-index, .timeline-date { display: block; color: var(--color-accent); font-family: var(--font-outlier); font-size: var(--text-xs); letter-spacing: .12em; }
.feature-card h3, .fit-card h3, .timeline h3, .platform-card h2, .step-list h3 { margin: var(--space-md) 0 var(--space-sm); font-family: var(--font-display); font-size: var(--text-lg); line-height: 1.15; }
.feature-card p, .fit-card p, .timeline p, .platform-card p, .step-list p { margin: 0; color: var(--color-muted); }
.gallery-section { background: var(--color-paper-2); }
.gallery-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-md); }
.gallery-card { min-width: 0; margin: 0; }
.gallery-card button { position: relative; display: block; width: 100%; padding: 0; overflow: hidden; border: 0; background: transparent; cursor: pointer; }
.gallery-card img { aspect-ratio: 16 / 9; width: 100%; object-fit: cover; transition: transform var(--dur-mid) var(--ease-out), filter var(--dur-mid) var(--ease-out); }
.gallery-card button:hover img, .gallery-card button:focus-visible img { transform: scale(1.03); filter: brightness(1.08); }
.gallery-card-wash { position: absolute; inset: 0; background: linear-gradient(180deg, transparent 45%, color-mix(in oklab, var(--color-paper) 32%, transparent)); pointer-events: none; }
.gallery-card figcaption { display: flex; align-items: center; justify-content: space-between; gap: var(--space-sm); padding-top: var(--space-sm); color: var(--color-muted); font-size: var(--text-sm); }
.text-link { display: inline-flex; align-items: center; gap: var(--space-sm); margin-top: var(--space-lg); border-bottom: 1px solid var(--color-accent); padding-bottom: var(--space-xs); color: var(--color-ink); font-weight: 700; transition: color var(--dur-short) var(--ease-out); }
.text-link:hover { color: var(--color-accent); }
.download-band, .final-band { background: var(--color-ink); color: var(--color-paper); }
.download-band-inner, .final-band-inner { display: flex; align-items: end; justify-content: space-between; gap: var(--space-2xl); padding-block: var(--space-4xl); }
.download-band .eyebrow, .final-band .eyebrow { color: var(--color-accent); }
.download-band h2, .final-band h2 { color: var(--color-paper); }
.download-band p:not(.eyebrow), .final-band p:not(.eyebrow) { max-width: 52ch; color: var(--color-ink-soft); }
.timeline { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-2xl); }
.timeline article { padding-top: var(--space-md); border-top: 1px solid var(--color-line-strong); }
.fit-section { background: var(--color-paper-2); }
.fit-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-lg); }
.fit-card { padding: var(--space-lg); background: var(--color-paper-3); }
.faq-list { max-width: 900px; }
.faq-item { border-top: 1px solid var(--color-line-strong); }
.faq-item:last-child { border-bottom: 1px solid var(--color-line-strong); }
.faq-item summary { display: flex; align-items: center; justify-content: space-between; gap: var(--space-lg); padding-block: var(--space-lg); cursor: pointer; list-style: none; font-family: var(--font-display); font-size: var(--text-md); font-weight: 700; line-height: 1.2; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary b { color: var(--color-accent); font-family: var(--font-outlier); font-size: var(--text-lg); font-weight: 400; }
.faq-item[open] summary b { transform: rotate(45deg); }
.faq-answer { max-width: 65ch; padding: 0 0 var(--space-lg); color: var(--color-muted); }
.faq-answer p { margin: 0; }
.final-band-inner { display: block; padding-block: var(--space-4xl) var(--space-5xl); }
.final-band h2 { max-width: 12ch; }
.final-band .button { margin-top: var(--space-lg); }
.site-footer { padding-block: var(--space-3xl) var(--space-lg); background: var(--color-paper-3); }
.footer-layout { display: grid; grid-template-columns: 1.4fr .7fr .9fr; gap: var(--space-3xl); }
.footer-brand img { width: 120px; height: 64px; object-fit: cover; object-position: 50% 50%; }
.footer-brand p { max-width: 36ch; margin: var(--space-md) 0 0; color: var(--color-muted); }
.footer-legal { font-size: var(--text-xs); }
.site-footer h2 { margin: 0 0 var(--space-md); color: var(--color-ink); font-size: var(--text-sm); }
.footer-links { display: grid; gap: var(--space-sm); margin: 0; padding: 0; list-style: none; }
.footer-links a { color: var(--color-muted); font-size: var(--text-sm); transition: color var(--dur-short) var(--ease-out); }
.footer-links a:hover { color: var(--color-accent); }
.footer-bottom { display: flex; align-items: center; justify-content: space-between; gap: var(--space-lg); margin-top: var(--space-3xl); padding-top: var(--space-md); border-top: 1px solid var(--color-line); color: var(--color-muted); font-size: var(--text-xs); }
.page-lead, .article-hero { padding: 180px 0 var(--space-3xl); background: var(--color-paper-2); }
.page-lead p:last-child, .article-hero p:last-child { max-width: 60ch; margin: var(--space-lg) 0 0; color: var(--color-muted); font-size: var(--text-md); }
.filter-tabs { display: flex; align-items: center; flex-wrap: wrap; gap: var(--space-sm); margin-bottom: var(--space-2xl); }
.filter-tabs button { min-height: 40px; padding: 0 var(--space-md); border: 1px solid var(--color-line-strong); background: transparent; color: var(--color-muted); cursor: pointer; transition: color var(--dur-short) var(--ease-out), background-color var(--dur-short) var(--ease-out), border-color var(--dur-short) var(--ease-out); }
.filter-tabs button:hover, .filter-tabs button[aria-selected="true"] { border-color: var(--color-accent); background: var(--color-accent); color: var(--color-accent-ink); }
.gallery-grid--large { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.empty-gallery { padding: var(--space-2xl); background: var(--color-paper-2); color: var(--color-muted); text-align: center; }
.platform-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-lg); }
.platform-card { min-height: 260px; display: flex; flex-direction: column; align-items: flex-start; padding: var(--space-2xl); border: 1px solid var(--color-line-strong); }
.platform-card--primary { background: var(--color-paper-2); }
.platform-card--muted { background: var(--color-paper-3); }
.platform-card .button { margin-top: auto; }
.platform-label, .platform-status { color: var(--color-accent); font-family: var(--font-outlier); font-size: var(--text-xs); letter-spacing: .1em; text-transform: uppercase; }
.platform-status { margin-top: auto; color: var(--color-muted); }
.steps-section, .notice-section { padding-block: var(--space-4xl); background: var(--color-paper-2); }
.step-list { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-lg); margin: 0; padding: 0; list-style: none; }
.step-list li { display: flex; gap: var(--space-md); padding-top: var(--space-md); border-top: 1px solid var(--color-line-strong); }
.step-list li > span { color: var(--color-accent); font-family: var(--font-outlier); font-size: var(--text-sm); }
.requirements-table { overflow-x: auto; border-top: 1px solid var(--color-line-strong); }
.requirements-table > div { min-width: 680px; display: grid; grid-template-columns: 1fr 1.4fr 1.1fr; gap: var(--space-md); padding: var(--space-md) 0; border-bottom: 1px solid var(--color-line); }
.requirements-table strong { font-weight: 600; }
.requirements-table em { color: var(--color-muted); font-style: normal; }
.requirements-head { color: var(--color-muted); font-size: var(--text-sm); }
.notice-section > div { display: grid; grid-template-columns: .8fr 1.2fr; gap: var(--space-3xl); padding-top: var(--space-xl); border-top: 1px solid var(--color-line-strong); }
.notice-section h2 { margin: 0; font-family: var(--font-display); font-size: var(--text-xl); line-height: 1.1; }
.notice-section p:last-child { max-width: 65ch; margin: 0; color: var(--color-muted); }
.guide-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: var(--space-md); }
.guide-card { min-width: 0; min-height: 300px; display: flex; flex-direction: column; align-items: flex-start; padding: var(--space-lg); background: var(--color-paper-2); transition: transform var(--dur-mid) var(--ease-out), background-color var(--dur-mid) var(--ease-out); }
.guide-card:hover { transform: translateY(-4px); background: var(--color-paper-3); }
.guide-card > span { color: var(--color-accent); font-family: var(--font-outlier); font-size: var(--text-xs); }
.guide-card h2 { margin: var(--space-2xl) 0 var(--space-sm); font-family: var(--font-display); font-size: var(--text-lg); line-height: 1.15; }
.guide-card p { margin: 0; color: var(--color-muted); }
.guide-card strong { margin-top: auto; color: var(--color-accent); font-size: var(--text-sm); }
.guide-body { display: grid; grid-template-columns: 180px minmax(0, 1fr); gap: var(--space-3xl); align-items: start; }
.chapter-nav { position: sticky; top: calc(var(--nav-height) + var(--space-xl)); display: grid; gap: var(--space-sm); }
.chapter-nav a { color: var(--color-muted); font-size: var(--text-sm); transition: color var(--dur-short) var(--ease-out); }
.chapter-nav a:hover { color: var(--color-accent); }
.guide-copy { max-width: 72ch; }
.guide-copy article { padding-bottom: var(--space-4xl); scroll-margin-top: calc(var(--nav-height) + var(--space-xl)); }
.guide-copy h2 { margin: 0 0 var(--space-md); font-family: var(--font-display); font-size: var(--text-xl); line-height: 1.1; }
.guide-copy p { margin: 0 0 var(--space-lg); color: var(--color-muted); }
.number-list { display: grid; gap: var(--space-sm); margin: 0; padding-left: var(--space-lg); color: var(--color-ink-soft); }
.checklist { display: grid; gap: var(--space-sm); padding: var(--space-lg); background: var(--color-paper-2); }
.checklist label { display: flex; align-items: center; gap: var(--space-sm); color: var(--color-ink-soft); }
.checklist input { accent-color: var(--color-accent); }
.guide-table { width: 100%; border-collapse: collapse; margin-top: var(--space-lg); }
.guide-table th, .guide-table td { padding: var(--space-md) var(--space-sm); border-bottom: 1px solid var(--color-line); text-align: left; }
.guide-table th { color: var(--color-muted); font-size: var(--text-sm); font-weight: 500; }
.guide-callout { display: grid; gap: var(--space-sm); padding: var(--space-lg); background: var(--color-paper-2); }
.guide-callout strong { color: var(--color-accent); }
.article-links { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: var(--space-sm); }
.article-links a { display: flex; align-items: center; justify-content: space-between; gap: var(--space-sm); padding: var(--space-md); border-top: 1px solid var(--color-line-strong); color: var(--color-ink-soft); font-size: var(--text-sm); }
.article-links a:hover { color: var(--color-accent); }
.article-body { max-width: 820px; padding-block: var(--space-4xl); }
.article-answer { margin: 0 0 var(--space-3xl); padding: var(--space-lg); background: var(--color-paper-2); color: var(--color-ink-soft); font-size: var(--text-md); }
.article-body h2 { margin: var(--space-3xl) 0 var(--space-md); font-family: var(--font-display); font-size: var(--text-xl); line-height: 1.1; }
.article-body p { max-width: 65ch; color: var(--color-muted); }
.article-list { display: grid; gap: var(--space-sm); padding-left: var(--space-lg); color: var(--color-ink-soft); }
.article-note { display: grid; gap: var(--space-sm); margin-top: var(--space-3xl); padding: var(--space-lg); border-left: 2px solid var(--color-accent); background: var(--color-paper-2); color: var(--color-muted); }
.article-note strong { color: var(--color-ink); }
.article-links-inline { display: flex; align-items: center; flex-wrap: wrap; gap: var(--space-md); margin-top: var(--space-3xl); }
.article-links-inline a { color: var(--color-accent); border-bottom: 1px solid var(--color-accent); padding-bottom: var(--space-xs); }
.article-card-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-lg); }
.article-card { min-width: 0; display: flex; flex-direction: column; min-height: 300px; padding: var(--space-lg); background: var(--color-paper-2); transition: transform var(--dur-mid) var(--ease-out), background-color var(--dur-mid) var(--ease-out); }
.article-card:hover { transform: translateY(-4px); background: var(--color-paper-3); }
.article-card > span { color: var(--color-accent); font-family: var(--font-outlier); font-size: var(--text-xs); }
.article-card h2 { margin: var(--space-lg) 0 var(--space-md); font-family: var(--font-display); font-size: var(--text-lg); line-height: 1.15; }
.article-card p { margin: 0; color: var(--color-muted); }
.article-card strong { margin-top: auto; color: var(--color-accent); font-size: var(--text-sm); }
.lightbox { position: fixed; inset: 0; z-index: 600; display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: var(--space-md); padding: var(--space-lg); background: color-mix(in oklab, var(--color-paper) 94%, transparent); }
.lightbox[hidden] { display: none; }
.lightbox figure { min-width: 0; margin: 0; }
.lightbox-image { width: 100%; max-height: 80vh; object-fit: contain; }
.lightbox figcaption { margin-top: var(--space-sm); color: var(--color-muted); text-align: center; }
.lightbox-close, .lightbox-prev, .lightbox-next { min-height: 44px; padding: 0 var(--space-sm); border: 1px solid var(--color-line-strong); background: var(--color-paper-2); color: var(--color-ink); cursor: pointer; }
.lightbox-close { position: absolute; top: var(--space-lg); right: var(--space-lg); }
.lightbox-close:hover, .lightbox-prev:hover, .lightbox-next:hover { border-color: var(--color-accent); color: var(--color-accent); }
@keyframes shimmer { 0%, 70% { transform: translateX(0) skewX(-18deg); opacity: 0; } 78% { opacity: .7; } 100% { transform: translateX(560%) skewX(-18deg); opacity: 0; } }
@media (max-width: 1024px) {
  .feature-grid, .fit-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .guide-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .article-card-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  .site-header { inset: var(--space-sm) var(--space-sm) auto; }
  .site-nav { flex-wrap: wrap; }
  .site-mark span { font-size: var(--text-sm); }
  .nav-toggle { display: block; margin-left: auto; }
  .site-menu { order: 4; width: 100%; display: none; grid-template-columns: repeat(2, minmax(0, 1fr)); padding: var(--space-sm) 0 var(--space-xs); }
  .site-menu.is-open { display: grid; }
  .site-nav > .button { display: none; }
  .hero-fold { min-height: 680px; }
  .hero-copy { padding-bottom: var(--space-2xl); }
  .hero-annotation { top: 100px; right: var(--space-md); }
  .fact-ribbon, .reading-section, .notice-section { grid-template-columns: 1fr; }
  .fact-ribbon { gap: var(--space-sm); }
  .fact-ribbon > div, .fact-ribbon > div:first-child { padding: var(--space-sm) 0; border-left: 0; border-top: 1px solid var(--color-line); }
  .fact-ribbon > div:first-child { border-top: 0; }
  .reading-section { gap: var(--space-2xl); }
  .download-band-inner, .footer-bottom { align-items: flex-start; flex-direction: column; }
  .timeline, .platform-grid, .step-list, .guide-body { grid-template-columns: 1fr; }
  .chapter-nav { position: static; display: flex; flex-wrap: wrap; gap: var(--space-sm) var(--space-md); padding-bottom: var(--space-lg); border-bottom: 1px solid var(--color-line); }
  .article-links { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .gallery-grid, .gallery-grid--large { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-layout { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .site-shell { width: min(100% - (var(--space-md) * 2), 1180px); }
  .site-mark img { width: 36px; height: 24px; }
  .site-mark span { max-width: 14ch; overflow: hidden; text-overflow: ellipsis; }
  .hero-fold { min-height: 660px; }
  .hero-shade { background: linear-gradient(90deg, color-mix(in oklab, var(--color-paper) 88%, transparent), color-mix(in oklab, var(--color-paper) 38%, transparent)); }
  .hero-copy h1 { font-size: clamp(2.45rem, 13vw, 4.1rem); }
  .hero-lede { max-width: 35ch; }
  .hero-actions, .hero-actions .button { width: 100%; }
  .hero-actions .button { justify-content: center; }
  .feature-grid, .fit-grid, .gallery-grid, .gallery-grid--large, .guide-grid, .article-card-grid { grid-template-columns: 1fr; }
  .gallery-card img { aspect-ratio: 16 / 10; }
  .footer-layout { grid-template-columns: 1fr; }
  .page-lead, .article-hero { padding-top: 140px; }
  .reading-section, .feature-section, .gallery-section, .timeline-section, .fit-section, .faq-section, .platform-section, .requirements-section, .guide-index-section, .guide-body, .article-rail, .article-index { padding-block: var(--space-3xl); }
  .lightbox { grid-template-columns: 1fr; padding: var(--space-md); }
  .lightbox-prev, .lightbox-next { position: absolute; top: 50%; }
  .lightbox-prev { left: var(--space-sm); }
  .lightbox-next { right: var(--space-sm); }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}