:root {
  --color-surface: #fcfcfc;
  --color-surface-alt: #f3f3f3;
  --color-surface-deep: #e6e7e7;
  --color-ink: #454b4f;
  --color-ink-soft: #676f74;
  --color-ink-muted: #798186;
  --color-line: #dbdcdd;
  --color-primary: #2a7cb1;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #dfeaf2;
  --color-accent: #db1a89;
  --color-accent-ink: #ffffff;
  --color-highlight: #f6d3e7;
  --color-focus: #d80d82;
  --color-contrast-surface: #172229;
  --color-contrast-ink: #e4e6e7;
  --color-contrast-line: #444d53;
  --color-contrast-accent: #e949a5;
  --overlay-scrim: linear-gradient(180deg, rgba(23, 34, 41, 0.35) 0%, rgba(23, 34, 41, 0.72) 55%, rgba(23, 34, 41, 0.92) 100%);
  --font-heading: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-body: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --text-xs: 12.9px;
  --text-sm: 15.5px;
  --text-base: 17px;
  --text-lg: 20.4px;
  --text-xl: 24.5px;
  --text-2xl: 29.4px;
  --text-3xl: 35.3px;
  --text-4xl: 42.3px;
  --text-display: clamp(34px, 4.8vw, 62px);
  --text-figure: clamp(28px, 3.5vw, 45px);
  --weight-heading: 630;
  --weight-body: 400;
  --leading-body: 1.71;
  --leading-heading: 1.19;
  --tracking-heading: 0.005em;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-pill: 999px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: 0 1px 0 rgba(69, 75, 79, 0.12);
  --shadow-2: 0 2px 0 rgba(69, 75, 79, 0.18);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1280px;
  --measure: 74ch;
  --gutter: 32px;
  --section-y: 79px;
  --section-y-lg: 111px;
}

/* ================= 01 reset & base ================= */
*, *::before, *::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
}

img, svg, video { display: block; max-width: 100%; }

a { color: var(--color-primary); text-decoration: none; }
a:hover { text-decoration: underline; }

button { font: inherit; color: inherit; }

h1, h2, h3, h4, h5 {
  margin: 0 0 var(--space-2);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}
h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

p { margin: 0 0 var(--space-2); }
p:last-child { margin-bottom: 0; }

:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 2px;
}
.site-header :focus-visible,
.nav-scrim:focus-visible { outline-color: var(--color-contrast-accent); }

.skip-link {
  position: absolute;
  top: -120px;
  left: var(--space-2);
  z-index: 200;
  padding: 10px var(--space-2);
  background: var(--color-accent);
  color: var(--color-accent-ink);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  transition: top 140ms ease-out;
}
.skip-link:focus { top: var(--space-2); text-decoration: none; }

/* ================= 02 utilities ================= */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum" 1;
  letter-spacing: 0.01em;
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum" 1;
}
.num--key { color: var(--color-accent); font-weight: 600; }

.text-display {
  margin: 0;
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
}
.text-figure {
  margin: 0;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-figure);
  line-height: 1.05;
}

.eyebrow {
  display: inline-block;
  padding-left: 10px;
  border-left: 2px solid var(--color-line);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  color: var(--color-ink-muted);
  transition: border-color 140ms ease-out, color 140ms ease-out;
}

.prose { max-width: var(--measure); }
.prose p { margin-bottom: var(--space-2); }

.quote-note {
  max-width: var(--measure);
  margin: var(--space-3) 0 var(--space-3) var(--space-4);
  padding: 2px 0 2px var(--space-3);
  border-left: 2px solid var(--color-accent);
  color: var(--color-ink-soft);
  font-size: var(--text-base);
}
.quote-note::before { content: "“"; color: var(--color-accent); }
.quote-note::after { content: "”"; color: var(--color-accent); }

.rule {
  height: 0;
  margin: var(--space-3) 0;
  border: 0;
  border-top: var(--border-thin) solid var(--color-line);
}
.rule--step { margin-left: var(--space-6); }

.indent-1, .indent-2 { margin-left: 0; }

.grid { display: grid; gap: var(--space-3); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.split {
  display: grid;
  grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
  gap: var(--gutter);
  align-items: start;
}
.split__aside { display: flex; flex-direction: column; gap: var(--space-2); }

/* ================= 03 components ================= */
.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }

[data-section] { scroll-margin-top: 110px; }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-1) var(--space-3);
  padding-bottom: var(--space-2);
  margin-bottom: var(--space-3);
  border-bottom: var(--border-thin) solid var(--color-line);
}
.section__title { margin: 0; font-size: var(--text-xl); }
.section__note {
  margin: 0;
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
  max-width: var(--measure);
}
[data-section][data-active] .eyebrow {
  border-left-color: var(--color-accent);
  color: var(--color-accent);
}

.card {
  padding: var(--space-3);
  background: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  transition: transform 160ms ease-out, border-color 160ms ease-out;
}
.card:hover { transform: translateY(-2px); border-color: var(--color-primary); }
.card__title { margin: 0 0 var(--space-1); font-size: var(--text-lg); }
.card__meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.panel {
  padding: var(--space-3);
  background: var(--color-surface-deep);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
}
.panel--dark {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-line);
}
.panel--dark h2, .panel--dark h3, .panel--dark h4 { color: var(--color-contrast-ink); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 2px 8px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
}
.tag--accent { background: var(--color-highlight); color: var(--color-accent); }
.tag--mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  min-height: 44px;
  padding: 0 var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface-deep);
  color: var(--color-ink);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: background-color 140ms ease-out, border-color 140ms ease-out, color 140ms ease-out;
}
.btn:hover { text-decoration: none; border-color: var(--color-primary); }
.btn--primary {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}
.btn--primary:hover { border-color: var(--color-primary); background: color-mix(in srgb, var(--color-primary) 86%, #000); }
.btn--ghost { background: transparent; border-color: var(--color-line); color: var(--color-ink); }
.btn--accent {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}
.breadcrumb__item { display: inline-flex; gap: 6px; align-items: center; }
.breadcrumb__sep { color: var(--color-line); }

.table-scroll {
  overflow-x: auto;
  background: var(--color-surface);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
}
.data-table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
  font-size: var(--text-sm);
}
.data-table caption {
  padding: var(--space-2);
  text-align: left;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  border-bottom: var(--border-thin) solid var(--color-line);
}
.data-table th, .data-table td {
  padding: 10px var(--space-2);
  border-bottom: var(--border-thin) solid var(--color-line);
  text-align: left;
  vertical-align: top;
}
.data-table thead th {
  background: var(--color-surface-deep);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--color-ink-soft);
  white-space: nowrap;
}
.data-table tbody tr:nth-child(even) { background: var(--color-surface-alt); }
.data-table tbody tr:hover { background: var(--color-primary-soft); }
.data-table .num { text-align: right; }
.data-table .num--key { color: var(--color-accent); }

.media-frame {
  position: relative;
  overflow: hidden;
  background: var(--color-contrast-surface);
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: 0;
}
.media-frame__img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: var(--color-contrast-surface);
}
.media-frame--wide .media-frame__img { aspect-ratio: 21 / 9; }
.media-frame--portrait .media-frame__img { aspect-ratio: 3 / 4; }
.media-frame--square .media-frame__img { aspect-ratio: 1 / 1; }
.media-frame__ph {
  aspect-ratio: 16 / 9;
  background-color: var(--color-contrast-surface);
  background-image:
    repeating-linear-gradient(0deg, color-mix(in srgb, var(--color-contrast-ink) 7%, transparent) 0 1px, transparent 1px 4px),
    repeating-linear-gradient(90deg, color-mix(in srgb, var(--color-contrast-ink) 7%, transparent) 0 1px, transparent 1px 4px);
}
.media-frame--wide .media-frame__ph { aspect-ratio: 21 / 9; }
.media-frame--portrait .media-frame__ph { aspect-ratio: 3 / 4; }
.media-frame--square .media-frame__ph { aspect-ratio: 1 / 1; }
.media-frame__overlay {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
}
.media-frame__caption {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  padding: var(--space-2);
  color: var(--color-contrast-ink);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.02em;
}

/* ================= 04 header / rail ================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  display: flex;
  flex-direction: column;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
  transition: background-color 160ms ease-out;
}

.rail-status {
  order: 2;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 0 var(--space-2) var(--space-1);
}
.rail-status__line {
  margin: 0;
  overflow: hidden;
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
  white-space: nowrap;
  text-overflow: ellipsis;
  color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent);
}
.rail-status__line--soft { color: color-mix(in srgb, var(--color-contrast-ink) 48%, transparent); }
.rail-status__line .mono { color: var(--color-contrast-accent); }

.rail-head {
  order: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding: 10px var(--space-2);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--color-contrast-ink);
  text-decoration: none;
}
.brand:hover { text-decoration: none; }
.brand__mark {
  display: grid;
  flex: none;
  place-items: center;
  width: 34px;
  height: 34px;
  border: var(--border-thin) solid var(--color-contrast-accent);
  border-radius: var(--radius-sm);
  color: var(--color-contrast-accent);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
}
.brand__text { display: flex; flex-direction: column; line-height: 1.15; }
.brand__name { font-size: var(--text-sm); font-weight: 600; letter-spacing: 0.04em; }
.brand__sub {
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: color-mix(in srgb, var(--color-contrast-ink) 58%, transparent);
}

.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 9px 10px;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-contrast-ink);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  cursor: pointer;
}
.nav-toggle:hover { border-color: var(--color-contrast-accent); }
.nav-toggle__bars {
  position: relative;
  display: block;
  width: 14px;
  height: 2px;
  background: currentColor;
}
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 14px;
  height: 2px;
  background: currentColor;
  transition: transform 140ms ease-out, opacity 140ms ease-out;
}
.nav-toggle__bars::before { top: -4px; }
.nav-toggle__bars::after { top: 4px; }
.site-header[data-open] .nav-toggle__bars { background: transparent; }
.site-header[data-open] .nav-toggle__bars::before { transform: translateY(4px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars::after { transform: translateY(-4px) rotate(-45deg); }
.nav-toggle__label { line-height: 1; }

.site-nav {
  position: absolute;
  top: 100%;
  right: 0;
  left: 0;
  display: none;
  max-height: calc(100vh - 72px);
  overflow-y: auto;
  padding: var(--space-2) var(--space-2) var(--space-3);
  background: var(--color-contrast-surface);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}
.site-header[data-open] .site-nav { display: block; }

.nav-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.nav-list__item { list-style: none; }
.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: 11px var(--space-2);
  border-left: 2px solid transparent;
  border-radius: var(--radius-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 78%, transparent);
  font-size: var(--text-sm);
  transition: background-color 120ms ease-out, color 120ms ease-out, border-color 120ms ease-out;
}
.nav-link:hover {
  background: color-mix(in srgb, var(--color-contrast-ink) 8%, transparent);
  color: var(--color-contrast-ink);
  text-decoration: none;
}
.nav-link[aria-current="page"] {
  background: color-mix(in srgb, var(--color-contrast-accent) 14%, transparent);
  border-left-color: var(--color-contrast-accent);
  color: var(--color-contrast-ink);
}
.nav-link__index {
  min-width: 2ch;
  color: var(--color-contrast-accent);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
}
.nav-link__label { line-height: 1.3; }

.rail-foot { display: none; }

.rail-now {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-1);
  padding-bottom: 10px;
  font-size: var(--text-xs);
}
.rail-now__label { letter-spacing: 0.12em; color: color-mix(in srgb, var(--color-contrast-ink) 50%, transparent); }
.rail-now__value {
  overflow: hidden;
  font-family: var(--font-mono);
  color: var(--color-contrast-accent);
  white-space: nowrap;
  text-overflow: ellipsis;
}

.rail-search {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 10px var(--space-2);
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  color: var(--color-contrast-ink);
  transition: border-color 120ms ease-out, background-color 120ms ease-out;
}
.rail-search:hover {
  border-color: var(--color-contrast-accent);
  background: color-mix(in srgb, var(--color-contrast-ink) 6%, transparent);
  text-decoration: none;
}
.rail-search__label { font-size: var(--text-sm); }
.rail-search__hint {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 55%, transparent);
}

.rail-progress {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  height: 2px;
  background: color-mix(in srgb, var(--color-contrast-ink) 14%, transparent);
  opacity: 0;
  transition: opacity 160ms ease-out;
}
.site-header[data-scrolled] .rail-progress { opacity: 1; }
.rail-progress__bar {
  display: block;
  width: 0;
  height: 100%;
  background: var(--color-contrast-accent);
  transition: width 120ms linear;
}

.nav-scrim { display: none; }

@media (max-width: 1024px) {
  .nav-open { overflow: hidden; }
  .nav-scrim:not([hidden]) {
    position: fixed;
    inset: 0;
    z-index: 70;
    display: block;
    background: color-mix(in srgb, var(--color-contrast-surface) 62%, transparent);
  }
}

@media (min-width: 1025px) {
  body { padding-left: 240px; }

  .site-header {
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    width: 240px;
    height: 100vh;
    overflow: hidden;
    border-bottom: 0;
    border-right: var(--border-thin) solid var(--color-contrast-line);
    background: var(--color-contrast-surface);
    background: color-mix(in srgb, var(--color-contrast-surface) 93%, transparent);
  }
  .site-header[data-scrolled] { background: var(--color-contrast-surface); }

  .rail-status {
    order: 1;
    padding: var(--space-2);
    border-bottom: var(--border-thin) solid var(--color-contrast-line);
  }
  .rail-head { order: 2; padding: var(--space-3) var(--space-2) var(--space-2); }
  .site-nav {
    position: static;
    order: 3;
    flex: 1 1 auto;
    display: block;
    max-height: none;
    padding: var(--space-2);
    border-bottom: 0;
    overflow-y: auto;
    background: transparent;
  }
  .nav-toggle { display: none; }

  .rail-foot {
    order: 4;
    display: block;
    padding: var(--space-2);
    border-top: var(--border-thin) solid var(--color-contrast-line);
  }
  .nav-scrim { display: none !important; }
}

/* ================= 05 footer ================= */
.site-footer {
  background: var(--color-surface);
  color: var(--color-ink);
  border-top: var(--border-thin) solid var(--color-line);
}

.footer-upper {
  padding-block: var(--space-6) var(--space-4);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}
.footer-upper__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-4);
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.footer-step { display: flex; flex-direction: column; gap: var(--space-2); }

.footer-col__title {
  display: flex;
  align-items: baseline;
  gap: var(--space-1);
  margin: 0;
  padding-bottom: 8px;
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.16em;
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}
.footer-col__title .mono { color: var(--color-contrast-accent); }

.footer-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.footer-list__item { list-style: none; }
.footer-link {
  display: inline-block;
  padding: 2px 0;
  border-bottom: var(--border-thin) solid transparent;
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent);
  font-size: var(--text-sm);
}
.footer-link:hover {
  border-bottom-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
  text-decoration: none;
}

.footer-lower {
  padding-block: var(--space-4) var(--space-6);
  background: var(--color-surface);
}
.footer-lower__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-4);
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.footer-sign { display: flex; flex-direction: column; gap: 10px; }
.footer-sign__brand {
  margin: 0;
  color: var(--color-ink);
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
}
.footer-sign__note {
  max-width: 56ch;
  margin: 0;
  color: var(--color-ink-muted);
  font-size: var(--text-xs);
  line-height: 1.7;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 4px var(--space-2);
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}
.footer-legal__item { display: inline-flex; align-items: center; gap: 4px; }
.footer-legal__item + .footer-legal__item::before { content: "·"; color: var(--color-line); }
.footer-legal .mono { color: var(--color-ink-soft); }

.footer-meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 0;
  font-size: var(--text-sm);
}
.footer-contact__row {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: var(--space-2);
  align-items: baseline;
  margin: 0;
  padding: 10px 0;
  border-bottom: var(--border-thin) solid var(--color-line);
}
.footer-contact__row:first-child { border-top: var(--border-thin) solid var(--color-line); }
.footer-contact__key {
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
}
.footer-contact__val { color: var(--color-ink-soft); }

@media (min-width: 768px) {
  .footer-upper__inner { grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr) minmax(0, 0.9fr); }
  .footer-step--b { margin-top: var(--space-3); }
  .footer-step--c { margin-top: var(--space-6); }
  .footer-lower__inner {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
    gap: var(--space-6);
  }
  .footer-contact { padding-top: var(--space-3); }
  .indent-1 { margin-left: var(--space-4); }
  .indent-2 { margin-left: var(--space-8); }
}

/* ================= 06 responsive ================= */
@media (max-width: 1023px) {
  .split { grid-template-columns: minmax(0, 1fr); }
  .grid--3, .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 639px) {
  :root { --gutter: 20px; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .rule--step { margin-left: 0; }
  .footer-contact__row { grid-template-columns: minmax(0, 1fr); gap: 2px; }
}

/* ================= 07 motion ================= */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  .site-header { background: var(--color-contrast-surface); }
  .rail-progress { opacity: 1; }
  .card:hover { transform: none; }
}