.page-contact {
  --co-tab-w: 232px;
  --co-accent-soft: rgba(77, 240, 200, 0.14);
  display: block;
  padding-bottom: clamp(40px, 6vw, 88px);
}

/* 面包屑 */
.page-contact .co-crumb {
  padding-top: clamp(18px, 3vw, 30px);
}

/* ── 首屏 ───────────────────────────── */
.page-contact .co-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(34px, 6vw, 76px) 0 clamp(30px, 5vw, 56px);
  border-bottom: 1px solid var(--border-soft);
}

.page-contact .co-hero::before {
  content: "";
  position: absolute;
  inset: -20% -10% auto auto;
  width: min(680px, 90%);
  height: 130%;
  background:
    linear-gradient(160deg, rgba(77, 240, 200, 0.16) 0%, rgba(77, 240, 200, 0) 58%),
    repeating-linear-gradient(112deg, rgba(28, 107, 82, 0.34) 0 1px, transparent 1px 26px);
  transform: skewX(-9deg);
  pointer-events: none;
}

.page-contact .co-hero__inner {
  position: relative;
  display: grid;
  gap: clamp(24px, 4vw, 48px);
}

.page-contact .co-hero__eyebrow {
  color: var(--neon);
  margin: 0 0 14px;
}

.page-contact .co-hero__title {
  margin: 0;
  font-size: clamp(36px, 8.4vw, 82px);
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--fg);
  transform: scaleX(0.97);
  transform-origin: left center;
}

.page-contact .co-hero__lede {
  margin: clamp(16px, 3vw, 26px) 0 0;
  max-width: 46ch;
  color: var(--fg-mute);
}

.page-contact .co-hero__chips {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-content: flex-start;
}

.page-contact .co-hero__chips .chip {
  white-space: nowrap;
}

/* ── 章节标题行 ─────────────────────── */
.page-contact .co-head {
  margin-bottom: clamp(22px, 4vw, 40px);
}

.page-contact .co-head__note,
.page-contact .section-head__note {
  color: var(--fg-mute);
}

/* ── 合作方向：左右分屏 ───────────────── */
.page-contact .co-directions {
  padding: clamp(42px, 7vw, 84px) 0 clamp(34px, 6vw, 64px);
}

.page-contact .co-split {
  display: grid;
  gap: clamp(22px, 3vw, 40px);
}

.page-contact .co-tablist {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  padding-bottom: 8px;
  scroll-snap-type: x proximity;
}

.page-contact .co-tab {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 18px;
  scroll-snap-align: start;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--fg-mute);
  font-family: var(--font-body);
  font-size: 15px;
  cursor: pointer;
  transition: color 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.page-contact .co-tab__num {
  font-size: 12px;
  color: var(--fg-dim);
  transition: color 180ms ease;
}

.page-contact .co-tab:hover {
  color: var(--fg);
  border-color: var(--border-hot);
}

.page-contact .co-tab[aria-selected="true"] {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-on);
}

.page-contact .co-tab[aria-selected="true"] .co-tab__num {
  color: rgba(4, 20, 15, 0.62);
}

.page-contact .co-tab:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: 2px;
}

.page-contact .co-panels {
  position: relative;
}

.page-contact .co-panel {
  position: relative;
  padding: clamp(22px, 3.4vw, 40px);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-contact .co-panel::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: var(--accent);
}

.page-contact .co-panel__title {
  margin: 0 0 10px;
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--fg);
}

.page-contact .co-panel__lede {
  margin: 0 0 clamp(20px, 3vw, 30px);
  color: var(--fg-mute);
  max-width: 44ch;
}

.page-contact .co-panel__block {
  padding: 16px 0 0;
  border-top: 1px solid var(--border-soft);
}

.page-contact .co-panel__block + .co-panel__block {
  margin-top: 16px;
}

.page-contact .co-panel__label {
  margin: 0 0 6px;
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--neon);
  font-weight: 700;
}

.page-contact .co-panel__block p {
  margin: 0;
  color: var(--fg);
  max-width: 52ch;
  line-height: 1.75;
}

/* 接口示意图 */
.page-contact .co-api-diagram {
  margin: clamp(22px, 3vw, 32px) 0 0;
  padding: 14px 16px 10px;
  background: var(--bg-sunk);
  border: 1px dashed var(--border);
  border-radius: var(--radius-sm);
}

.page-contact .co-api-svg {
  display: block;
  width: 100%;
  max-width: 640px;
  height: auto;
}

.page-contact .co-api-caption {
  margin: 8px 0 0;
  font-size: 12px;
  color: var(--fg-dim);
}

/* ── 流程四步 ───────────────────────── */
.page-contact .co-flow {
  padding: clamp(40px, 6vw, 76px) 0;
  background: linear-gradient(180deg, rgba(10, 42, 32, 0) 0%, rgba(10, 42, 32, 0.85) 40%, rgba(10, 42, 32, 0) 100%);
}

.page-contact .co-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
  counter-reset: co-step;
}

.page-contact .co-step details {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 3px solid var(--line);
  border-radius: var(--radius-sm);
  transition: border-color 200ms ease, border-left-color 200ms ease;
}

.page-contact .co-step details[open] {
  border-left-color: var(--accent);
}

.page-contact .co-step details:hover {
  border-color: var(--border-hot);
  border-left-color: var(--accent);
}

.page-contact .co-step summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

.page-contact .co-step summary::-webkit-details-marker {
  display: none;
}

.page-contact .co-step summary:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: -2px;
}

.page-contact .co-step__no {
  font-size: 13px;
  color: var(--neon);
  flex: 0 0 auto;
}

.page-contact .co-step__name {
  flex: 1 1 auto;
  font-size: clamp(16px, 2.2vw, 20px);
  font-weight: 700;
  color: var(--fg);
}

.page-contact .co-step__tag {
  flex: 0 0 auto;
}

.page-contact .co-step__body {
  padding: 0 18px 18px 44px;
}

.page-contact .co-step__body p {
  margin: 0;
  color: var(--fg-mute);
  max-width: 56ch;
  line-height: 1.75;
}

/* ── 地域与到访 ─────────────────────── */
.page-contact .co-region {
  padding: clamp(36px, 6vw, 72px) 0;
}

.page-contact .co-region__inner {
  display: grid;
  gap: clamp(22px, 4vw, 44px);
  align-items: center;
}

.page-contact .co-region__title {
  margin: 8px 0 clamp(14px, 2.4vw, 22px);
  font-size: clamp(28px, 5vw, 54px);
  line-height: 1.06;
  color: var(--fg);
}

.page-contact .co-region__para {
  margin: 0 0 14px;
  color: var(--fg-mute);
  max-width: 46ch;
  line-height: 1.8;
}

.page-contact .co-region__media {
  margin: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg-sunk);
}

.page-contact .co-region__media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.85) contrast(1.05);
}

/* ── 联系信息带 ─────────────────────── */
.page-contact .co-band {
  padding: clamp(38px, 6vw, 78px) 0;
  background: var(--bg-raise);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border-soft);
}

.page-contact .co-head--band .section-head__title {
  color: var(--fg);
}

.page-contact .co-band__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-contact .co-band__item {
  display: grid;
  gap: 6px;
  padding: 18px 20px;
  background: rgba(4, 20, 15, 0.55);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-sm);
  transition: border-color 200ms ease, background-color 200ms ease;
}

.page-contact .co-band__item:hover {
  border-color: var(--border-hot);
  background: rgba(16, 64, 47, 0.5);
}

.page-contact .co-band__key {
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--fg-dim);
}

.page-contact .co-band__val {
  font-size: clamp(17px, 3.2vw, 26px);
  font-weight: 700;
  color: var(--neon);
  word-break: break-word;
  line-height: 1.3;
}

.page-contact .co-band__val--text {
  font-family: var(--font-body);
  font-weight: 500;
  color: var(--fg);
  font-size: clamp(16px, 2.6vw, 20px);
}

.page-contact .co-band__sub {
  font-size: 13px;
  color: var(--fg-mute);
}

.page-contact .co-band__note {
  margin: clamp(20px, 3vw, 28px) 0 0;
  font-size: 14px;
  color: var(--fg-mute);
  max-width: 62ch;
  line-height: 1.8;
}

.page-contact .co-band__note a {
  color: var(--neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(77, 240, 200, 0.4);
}

.page-contact .co-band__note a:hover {
  color: var(--neon-soft);
  border-bottom-color: var(--neon-soft);
}

/* ── 常见问题 ───────────────────────── */
.page-contact .co-faq {
  padding: clamp(40px, 6vw, 76px) 0 0;
}

.page-contact .co-faq__list {
  display: grid;
  gap: 12px;
}

.page-contact .co-faq__item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: border-color 200ms ease;
}

.page-contact .co-faq__item[open] {
  border-color: var(--border-hot);
}

.page-contact .co-faq__item summary {
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
  font-weight: 700;
  color: var(--fg);
  font-size: clamp(15px, 2vw, 17px);
  position: relative;
  padding-right: 44px;
}

.page-contact .co-faq__item summary::-webkit-details-marker {
  display: none;
}

.page-contact .co-faq__item summary::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  color: var(--neon);
  font-size: 18px;
}

.page-contact .co-faq__item[open] summary::after {
  content: "–";
}

.page-contact .co-faq__item summary:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: -2px;
}

.page-contact .co-faq__item p {
  margin: 0;
  padding: 0 18px 18px;
  color: var(--fg-mute);
  max-width: 62ch;
  line-height: 1.8;
}

/* ── 收尾 ───────────────────────────── */
.page-contact .co-cta {
  margin-top: clamp(32px, 5vw, 56px);
  padding: clamp(22px, 3.4vw, 36px);
  background: linear-gradient(120deg, rgba(77, 240, 200, 0.12) 0%, rgba(4, 20, 15, 0) 62%);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  display: grid;
  gap: 18px;
}

.page-contact .co-cta__text {
  margin: 0;
  color: var(--fg);
  max-width: 52ch;
  line-height: 1.75;
}

.page-contact .co-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ── 中等宽度 ───────────────────────── */
@media (min-width: 700px) {
  .page-contact .co-hero__inner {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-contact .co-band__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-contact .co-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ── 桌面：左右分屏 ─────────────────── */
@media (min-width: 980px) {
  .page-contact .co-hero__inner {
    grid-template-columns: minmax(0, 1.6fr) minmax(220px, 1fr);
    align-items: end;
  }

  .page-contact .co-hero__chips {
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-end;
    padding-bottom: 12px;
  }

  .page-contact .co-split {
    grid-template-columns: var(--co-tab-w) minmax(0, 1fr);
    gap: clamp(28px, 3.6vw, 52px);
    align-items: start;
  }

  .page-contact .co-tablist {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
    position: sticky;
    top: 96px;
  }

  .page-contact .co-tab {
    width: 100%;
    justify-content: flex-start;
    padding: 16px 18px;
    border-left: 3px solid transparent;
  }

  .page-contact .co-tab[aria-selected="true"] {
    border-left-color: var(--accent-on);
  }

  .page-contact .co-panel {
    min-height: 420px;
  }

  .page-contact .co-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .page-contact .co-region__inner {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
  }

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

  .page-contact .co-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

@media (min-width: 1240px) {
  .page-contact .co-step__body {
    padding-left: 52px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-contact .co-tab,
  .page-contact .co-step details,
  .page-contact .co-band__item,
  .page-contact .co-faq__item {
    transition: none;
  }
}