.page-contact {
  --contact-rail-w: 236px;
  --contact-sticky-top: 96px;
  --contact-glow: color-mix(in srgb, var(--color-accent) 34%, transparent);
  position: relative;
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */

.page-contact .contact-intro {
  position: relative;
  isolation: isolate;
  border-bottom: var(--border-thin) solid var(--color-line);
  padding-top: calc(var(--section-y) / 2);
}

.page-contact .contact-intro::before {
  content: "";
  position: absolute;
  inset: -20% -10% -30% -10%;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(760px 380px at 14% 8%, color-mix(in srgb, var(--color-primary) 30%, transparent), transparent 70%),
    radial-gradient(640px 320px at 88% 0%, color-mix(in srgb, var(--color-accent) 11%, transparent), transparent 72%);
}

.page-contact .contact-intro::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.55;
  background-image: repeating-linear-gradient(
    to bottom,
    color-mix(in srgb, var(--color-ink) 6%, transparent) 0 1px,
    transparent 1px 9px
  );
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95), transparent 76%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95), transparent 76%);
}

.page-contact .contact-intro__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-4);
  align-items: start;
}

.page-contact .contact-rail {
  display: grid;
  gap: var(--space-2);
  padding: var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-lg);
  background: color-mix(in srgb, var(--color-surface-alt) 74%, transparent);
}

.page-contact .contact-rail__badge {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.page-contact .contact-rail__badge-code {
  display: inline-grid;
  place-items: center;
  width: var(--space-4);
  height: var(--space-4);
  border-radius: var(--radius-sm);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-accent) 42%, transparent);
  background: var(--color-primary-soft);
  color: var(--color-accent);
  font-size: var(--text-xs);
  font-weight: var(--weight-heading);
  letter-spacing: 0.08em;
}

.page-contact .contact-rail__badge-text {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  letter-spacing: 0.06em;
}

.page-contact .contact-rail__figure {
  position: relative;
  margin: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: var(--border-thin) solid var(--color-line);
}

.page-contact .contact-rail__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  filter: grayscale(0.4) contrast(1.08) brightness(0.8);
}

.page-contact .contact-rail__figure::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(158deg, color-mix(in srgb, var(--color-primary) 52%, transparent), transparent 62%);
  mix-blend-mode: screen;
}

.page-contact .contact-rail__figure-cap {
  position: absolute;
  left: var(--space-1);
  bottom: var(--space-1);
  z-index: 1;
  padding: 2px var(--space-1);
  border-radius: var(--radius-pill);
  background: color-mix(in srgb, var(--color-contrast-surface) 84%, transparent);
  color: var(--color-contrast-ink);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
}

.page-contact .contact-rail__strip {
  margin: 0;
  padding-left: var(--space-2);
  border-left: var(--border-thin) solid var(--color-line);
  writing-mode: vertical-rl;
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  color: var(--color-ink-muted);
  min-height: 96px;
}

.page-contact .contact-intro__body {
  display: grid;
  gap: var(--space-3);
}

.page-contact .contact-intro__title {
  margin: 0;
  max-width: 22ch;
  font-size: var(--text-2xl);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  font-weight: var(--weight-heading);
  color: color-mix(in srgb, var(--color-ink) 62%, var(--color-primary-ink));
}

.page-contact .contact-intro__lede {
  margin: 0;
  max-width: 62ch;
}

.page-contact .contact-intro__signal {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  margin: 0;
  padding-top: var(--space-2);
  border-top: var(--border-thin) solid var(--color-line);
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
}

/* ---------- 渠道卡片 ---------- */

.page-contact .contact-channels__top {
  display: grid;
  gap: var(--space-4);
  margin-bottom: var(--space-6);
}

.page-contact .contact-channels__note {
  margin: var(--space-2) 0 0;
  max-width: 60ch;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-contact .contact-channels__figure {
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-lg);
}

.page-contact .contact-cards {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-3);
}

.page-contact .contact-card {
  position: relative;
  display: grid;
  gap: var(--space-2);
  align-content: start;
  padding: var(--space-3);
  border-radius: var(--radius-lg);
}

.page-contact .contact-card__index {
  position: absolute;
  top: var(--space-2);
  right: var(--space-3);
  font-size: var(--text-sm);
  letter-spacing: 0.14em;
  color: var(--color-ink-muted);
}

.page-contact .contact-card__title {
  margin: 0;
  padding-right: var(--space-6);
  font-size: var(--text-lg);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: color-mix(in srgb, var(--color-ink) 70%, var(--color-primary-ink));
}

.page-contact .contact-card__value {
  margin: 0;
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  line-height: 1.5;
  color: var(--color-accent);
  overflow-wrap: anywhere;
  word-break: break-word;
}

.page-contact .contact-card__desc {
  margin: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-contact .contact-card__meta {
  margin: 0;
  padding-top: var(--space-2);
  border-top: var(--border-thin) solid var(--color-line);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

/* ---------- 响应节奏 ---------- */

.page-contact .contact-cadence__filter {
  margin-bottom: var(--space-4);
}

.page-contact .contact-cadence__list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: var(--border-thin) solid var(--color-line);
}

.page-contact .contact-cadence__item {
  display: grid;
  gap: var(--space-1);
  padding: var(--space-3) 0;
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-contact .contact-cadence__item .tag {
  justify-self: start;
}

.page-contact .contact-cadence__item .entry-title {
  margin: 0;
  font-size: var(--text-base);
  line-height: var(--leading-heading);
  font-weight: var(--weight-heading);
  color: color-mix(in srgb, var(--color-ink) 72%, var(--color-primary-ink));
}

.page-contact .contact-cadence__item .entry-desc {
  margin: 0;
  max-width: 68ch;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-contact .filter-empty {
  margin: var(--space-3) 0 0;
  padding: var(--space-2) var(--space-3);
  border: var(--border-thin) dashed var(--color-line);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
}

.page-contact .filter-empty[hidden] {
  display: none;
}

/* ---------- 准备信息 ---------- */

.page-contact .contact-prep {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-3);
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: none;
}

.page-contact .contact-prep__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--space-2);
  align-items: start;
  padding: var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background: color-mix(in srgb, var(--color-surface-alt) 58%, transparent);
}

.page-contact .contact-prep__num {
  display: inline-grid;
  place-items: center;
  min-width: var(--space-4);
  height: var(--space-4);
  padding: 0 var(--space-1);
  border-radius: var(--radius-sm);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-primary) 58%, transparent);
  background: var(--color-primary-soft);
  color: var(--color-accent);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
}

.page-contact .contact-prep__body {
  display: grid;
  gap: var(--space-1);
}

.page-contact .contact-prep__title {
  margin: 0;
  font-size: var(--text-base);
  line-height: var(--leading-heading);
  font-weight: var(--weight-heading);
  color: color-mix(in srgb, var(--color-ink) 68%, var(--color-primary-ink));
}

.page-contact .contact-prep__body p {
  margin: 0;
  max-width: 66ch;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* ---------- 地域与备案 ---------- */

.page-contact .contact-region__panel {
  display: grid;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-lg);
  background:
    linear-gradient(135deg, color-mix(in srgb, var(--color-primary) 26%, transparent), transparent 58%),
    color-mix(in srgb, var(--color-surface-alt) 82%, transparent);
  box-shadow: var(--shadow-1);
}

.page-contact .contact-region__main {
  display: grid;
  gap: var(--space-2);
}

.page-contact .contact-region__main h2 {
  margin: 0;
  font-size: var(--text-xl);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: color-mix(in srgb, var(--color-ink) 70%, var(--color-primary-ink));
}

.page-contact .contact-region__text {
  margin: 0;
  max-width: 62ch;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-contact .contact-region__badge {
  display: grid;
  gap: var(--space-1);
  align-content: center;
  justify-items: start;
  padding: var(--space-2) var(--space-3);
  border: var(--border-thin) solid var(--contact-glow);
  border-radius: var(--radius-pill);
  background: color-mix(in srgb, var(--color-surface-deep) 70%, transparent);
  box-shadow: var(--shadow-2);
  width: fit-content;
  max-width: 100%;
}

.page-contact .contact-region__badge-code {
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  letter-spacing: 0.04em;
  color: var(--color-accent);
  overflow-wrap: anywhere;
}

.page-contact .contact-region__badge-note {
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
}

/* ---------- 下一步 ---------- */

.page-contact .contact-next__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--space-3);
}

.page-contact .contact-next__card {
  display: grid;
  gap: var(--space-2);
  align-content: start;
  padding: var(--space-3);
  border-radius: var(--radius-lg);
  text-decoration: none;
  color: inherit;
}

.page-contact .contact-next__kicker {
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  color: var(--color-accent);
}

.page-contact .contact-next__card-title {
  margin: 0;
  font-size: var(--text-lg);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: color-mix(in srgb, var(--color-ink) 70%, var(--color-primary-ink));
}

.page-contact .contact-next__card-desc {
  margin: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-contact a.contact-next__card:hover,
.page-contact a.contact-next__card:focus-visible {
  border-color: var(--contact-glow);
  box-shadow: var(--shadow-2);
}

.page-contact a.contact-next__card:hover .link-arrow,
.page-contact a.contact-next__card:focus-visible .link-arrow {
  color: var(--color-focus);
}

.page-contact .contact-next__card--legal .contact-next__kicker {
  color: var(--color-contrast-accent);
}

.page-contact .contact-next__card--legal .contact-next__card-title {
  color: var(--color-contrast-ink);
}

.page-contact .contact-next__card--legal .contact-next__card-desc {
  color: var(--color-contrast-ink);
}

.page-contact .contact-next__legal-links {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  align-items: center;
  font-size: var(--text-sm);
  color: var(--color-contrast-accent);
}

.page-contact .contact-next__legal-links a {
  color: var(--color-contrast-accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-contact .contact-next__fallback {
  margin: var(--space-4) 0 0;
  padding-top: var(--space-3);
  border-top: var(--border-thin) solid var(--color-line);
  max-width: 70ch;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-contact .contact-next__fallback a {
  color: var(--color-accent);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-contact .contact-prep {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-3);
  }
}

@media (min-width: 760px) {
  .page-contact .contact-intro__title {
    font-size: var(--text-3xl);
  }

  .page-contact .contact-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-contact .contact-next__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-contact .contact-intro__grid {
    grid-template-columns: var(--contact-rail-w) minmax(0, 1fr);
    gap: var(--space-6);
  }

  .page-contact .contact-rail {
    position: sticky;
    top: var(--contact-sticky-top);
  }

  .page-contact .contact-channels__top {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    gap: var(--space-6);
    align-items: end;
  }

  .page-contact .contact-cards {
    gap: var(--space-4);
    padding-bottom: var(--space-6);
  }

  .page-contact .contact-card:nth-child(2) {
    transform: translateY(var(--space-3));
  }

  .page-contact .contact-card:nth-child(3) {
    transform: translateY(var(--space-6));
  }

  .page-contact .contact-region__panel {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: var(--space-6);
    padding: var(--space-6) var(--space-4);
  }
}

@media (min-width: 1100px) {
  .page-contact .contact-cadence__item {
    grid-template-columns: 96px minmax(0, 1fr);
    grid-template-areas:
      "tag title"
      "tag desc";
    column-gap: var(--space-3);
    align-items: start;
  }

  .page-contact .contact-cadence__item .tag {
    grid-area: tag;
    margin-top: 4px;
  }

  .page-contact .contact-cadence__item .entry-title {
    grid-area: title;
  }

  .page-contact .contact-cadence__item .entry-desc {
    grid-area: desc;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-contact .contact-card,
  .page-contact a.contact-next__card {
    transition: none;
  }
}
</main>