.page-about {
  --about-line: rgba(140, 104, 59, 0.28);
  --about-gap: clamp(28px, 5vw, 64px);
  --about-ink: #131A17;
  --about-body-ink: #33443D;
  background-color: var(--ink-deep);
  color: var(--text-base);
  font-family: var(--font-body);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding-block: clamp(18px, 3vw, 28px) clamp(34px, 5vw, 60px);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(120% 80% at 92% -10%, rgba(184, 137, 78, 0.26), transparent 62%),
    linear-gradient(180deg, #0C2A24 0%, #123029 60%, #0C2A24 100%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.55;
  background-image: linear-gradient(to right, rgba(184, 137, 78, 0.10) 1px, transparent 1px);
  background-size: 86px 100%;
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(24px, 4vw, 42px);
  margin-top: clamp(18px, 3vw, 32px);
}

.page-about .about-hero__eyebrow {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--copper);
}

.page-about .about-hero__title {
  margin: 0 0 20px;
}

.page-about .about-hero__title-mark {
  display: block;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(76px, 21vw, 188px);
  line-height: 0.82;
  letter-spacing: 0.03em;
  color: var(--paper);
}

@supports ((-webkit-background-clip: text) or (background-clip: text)) {
  .page-about .about-hero__title-mark {
    background: linear-gradient(158deg, #F5EEE2 6%, var(--copper-bright) 52%, var(--copper) 96%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
  }
}

.page-about .about-hero__title-sub {
  display: block;
  margin-top: 16px;
  font-family: var(--font-mono);
  font-size: clamp(12px, 1.7vw, 14px);
  font-weight: 400;
  letter-spacing: 0.2em;
  color: var(--copper-bright);
}

.page-about .about-hero__desc {
  margin: 0 0 24px;
  max-width: 58ch;
  color: var(--text-dim);
  font-size: clamp(15px, 1.9vw, 17px);
  line-height: 1.85;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-hero__stats {
  padding: clamp(16px, 3vw, 22px);
  border: 1px solid var(--line-soft);
  background: rgba(245, 238, 226, 0.035);
}

.page-about .about-hero__stats-title {
  margin: 0 0 6px;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--copper);
}

.page-about .stat-list {
  margin: 0;
}

.page-about .stat-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .stat-row:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .stat-row dt {
  font-size: 12.5px;
  color: var(--text-faint);
  letter-spacing: 0.03em;
}

.page-about .stat-row dd {
  margin: 0;
  font-family: var(--font-mono);
  color: var(--copper-bright);
  white-space: nowrap;
}

.page-about .stat-num {
  font-size: 22px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.page-about .stat-unit {
  margin-left: 3px;
  font-size: 12px;
  color: var(--text-dim);
}

.page-about .about-hero__figure {
  margin: clamp(26px, 4vw, 44px) 0 0;
  border: 1px solid var(--line);
  background: var(--ink-green);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  filter: saturate(0.82) contrast(1.03) sepia(0.07);
}

.page-about .about-hero__caption {
  padding: 10px 14px;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--text-faint);
}

/* ---------- 主体布局 ---------- */
.page-about .about-body {
  display: grid;
  gap: var(--about-gap);
  padding-block: clamp(30px, 5vw, 72px);
}

.page-about .about-rail {
  border-top: 1px solid var(--line-soft);
  padding-top: 14px;
}

.page-about .about-rail__label {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--copper);
}

.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  margin: 12px 0 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 11px;
  border: 1px solid var(--line-soft);
  white-space: nowrap;
  font-size: 13px;
  color: var(--text-dim);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--copper-bright);
  border-color: var(--copper);
}

.page-about .about-rail__link[aria-current="true"] {
  color: var(--ink-deep);
  background: var(--copper-bright);
  border-color: var(--copper-bright);
}

.page-about .about-rail__no {
  font-size: 10.5px;
  letter-spacing: 0.12em;
  color: var(--copper);
}

.page-about .about-rail__link[aria-current="true"] .about-rail__no {
  color: var(--ink-deep);
}

.page-about .about-rail__cta {
  display: none;
  margin-top: 18px;
  padding: 10px 14px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--copper-bright);
  text-decoration: none;
  text-align: center;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .about-rail__cta:hover,
.page-about .about-rail__cta:focus-visible {
  background: var(--copper);
  color: var(--ink-deep);
}

/* ---------- 章节 ---------- */
.page-about .about-flow {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.page-about .chapter {
  padding-block: clamp(26px, 4.5vw, 52px);
  border-top: 1px solid var(--line-soft);
}

.page-about .chapter:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .chapter__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 18px;
}

.page-about .chapter__no {
  flex: none;
  padding: 3px 8px;
  border: 1px solid var(--line);
  font-size: 12.5px;
  letter-spacing: 0.14em;
  color: var(--copper);
}

.page-about .chapter__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3.6vw, 34px);
  line-height: 1.28;
  letter-spacing: 0.01em;
  color: var(--paper);
}

.page-about .chapter__body > p {
  max-width: 70ch;
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-dim);
}

.page-about .chapter__body > p:last-child {
  margin-bottom: 0;
}

.page-about .quote-card {
  margin: 22px 0;
  padding: 20px 22px;
  border-left: 2px solid var(--copper);
  background: rgba(232, 220, 199, 0.06);
}

.page-about .quote-card__text {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: clamp(18px, 2.7vw, 23px);
  line-height: 1.62;
  color: var(--paper);
}

.page-about .quote-card__note {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--copper);
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  position: relative;
  margin: 26px 0 0;
  padding: 0 0 0 30px;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--copper) 0%, rgba(184, 137, 78, 0.16) 100%);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: clamp(22px, 3vw, 30px);
}

.page-about .timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 6px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink-deep);
  border: 1px solid var(--copper-bright);
  box-shadow: 0 0 0 4px rgba(184, 137, 78, 0.10);
}

.page-about .timeline__stage {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--copper);
}

.page-about .timeline__title {
  margin: 7px 0 6px;
  font-family: var(--font-display);
  font-size: clamp(17px, 2.4vw, 20px);
  font-weight: 700;
  color: var(--paper);
}

.page-about .timeline__text {
  margin: 0;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

/* ---------- 团队与筛选 ---------- */
.page-about .team-block {
  margin-top: 22px;
}

.page-about .team-filter__input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.page-about .team-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .team-filter__label {
  padding: 7px 14px;
  border: 1px solid var(--line);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--text-dim);
  cursor: pointer;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .team-filter__label:hover {
  border-color: var(--copper-bright);
  color: var(--copper-bright);
}

.page-about #team-all:checked ~ .team-filter [for="team-all"],
.page-about #team-content:checked ~ .team-filter [for="team-content"],
.page-about #team-dev:checked ~ .team-filter [for="team-dev"],
.page-about #team-care:checked ~ .team-filter [for="team-care"] {
  background: var(--copper);
  border-color: var(--copper-bright);
  color: var(--ink-deep);
}

.page-about .team-filter__input:focus-visible ~ .team-filter [for="team-all"],
.page-about .team-filter__input:focus-visible ~ .team-filter [for="team-content"],
.page-about .team-filter__input:focus-visible ~ .team-filter [for="team-dev"],
.page-about .team-filter__input:focus-visible ~ .team-filter [for="team-care"] {
  outline: 2px solid var(--copper-bright);
  outline-offset: 2px;
}

.page-about #team-content:checked ~ .team-grid .team-card:not([data-team="content"]),
.page-about #team-dev:checked ~ .team-grid .team-card:not([data-team="dev"]),
.page-about #team-care:checked ~ .team-grid .team-card:not([data-team="care"]) {
  display: none;
}

.page-about .team-grid {
  display: grid;
  gap: 14px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .team-card {
  padding: 18px 18px 20px;
  background: var(--paper);
  color: var(--ink-black);
  border-top: 2px solid var(--copper);
  box-shadow: 0 1px 0 rgba(19, 26, 23, 0.08);
}

.page-about .team-card__tag {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--hairline);
}

.page-about .team-card__title {
  margin: 9px 0 7px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--ink-black);
}

.page-about .team-card__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--about-body-ink);
}

/* ---------- 图 ---------- */
.page-about .about-figure {
  margin: clamp(22px, 4vw, 34px) 0 0;
  border: 1px solid var(--line);
  background: var(--ink-green);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.8) contrast(1.02) sepia(0.08);
}

.page-about .about-figure--wide img {
  aspect-ratio: 3 / 2;
}

.page-about .about-figure--tall img {
  aspect-ratio: 10 / 7;
}

.page-about .about-figure figcaption {
  padding: 9px 12px;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--text-faint);
}

/* ---------- 复核流程 ---------- */
.page-about .review-flow {
  margin-top: 22px;
  border-top: 1px solid var(--line-soft);
}

.page-about .review-flow__item {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .review-flow__item summary {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 15px 0;
  list-style: none;
  cursor: pointer;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
  transition: color var(--dur) var(--ease);
}

.page-about .review-flow__item summary::-webkit-details-marker {
  display: none;
}

.page-about .review-flow__item summary:hover {
  color: var(--copper-bright);
}

.page-about .review-flow__item summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--copper-bright);
}

.page-about .review-flow__item[open] summary::after {
  content: "\2212";
}

.page-about .review-flow__no {
  flex: none;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--copper);
}

.page-about .review-flow__body {
  margin: 0;
  padding: 0 0 18px 34px;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--text-dim);
}

/* ---------- 覆盖与合作 ---------- */
.page-about .data-strip {
  display: grid;
  gap: 1px;
  margin-top: 22px;
  border: 1px solid var(--line-soft);
  background: var(--line-soft);
}

.page-about .data-strip__item {
  padding: 18px 16px;
  background: var(--ink-green);
}

.page-about .data-strip__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 4vw, 32px);
  line-height: 1.1;
  color: var(--copper-bright);
}

.page-about .data-strip__label {
  display: block;
  margin-top: 7px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--text-faint);
}

.page-about .partner-list {
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .partner-list__item {
  display: flex;
  gap: 14px;
  padding: 13px 0;
  border-top: 1px solid var(--line-soft);
  font-size: 15px;
  line-height: 1.78;
  color: var(--text-dim);
}

.page-about .partner-list__item span:first-child {
  flex: none;
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--copper);
}

/* ---------- 理由 ---------- */
.page-about .reason-list {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .reason-list__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  padding: clamp(16px, 3vw, 24px) 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .reason-list__no {
  padding-top: 4px;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--copper);
}

.page-about .reason-list__title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .reason-list__text {
  margin: 0;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

/* ---------- 结尾 ---------- */
.page-about .about-cta {
  margin-top: clamp(30px, 5vw, 56px);
  padding: clamp(24px, 4vw, 40px);
  border: 1px solid var(--line);
  background: linear-gradient(135deg, rgba(184, 137, 78, 0.18), rgba(23, 63, 53, 0.72));
}

.page-about .about-cta__kicker {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--copper-bright);
}

.page-about .about-cta__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(22px, 3.4vw, 30px);
  font-weight: 800;
  line-height: 1.3;
  color: var(--paper);
}

.page-about .about-cta__text {
  margin: 0 0 20px;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.82;
  color: var(--text-dim);
}

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

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .data-strip {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .chapter:nth-of-type(even) .chapter__head {
    flex-direction: row-reverse;
    justify-content: flex-end;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr) minmax(250px, 306px);
    align-items: start;
    gap: clamp(32px, 5vw, 64px);
  }

  .page-about .about-hero__stats {
    margin-top: 6px;
  }

  .page-about .about-body {
    grid-template-columns: 216px minmax(0, 1fr);
    gap: clamp(36px, 5vw, 76px);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 26px);
    border-top: 0;
    padding-top: 0;
  }

  .page-about .about-rail__list {
    display: block;
    overflow: visible;
    margin-top: 14px;
    padding-bottom: 0;
  }

  .page-about .about-rail__list li + li {
    margin-top: 2px;
  }

  .page-about .about-rail__link {
    display: flex;
    width: 100%;
    padding: 9px 0 9px 13px;
    border: 0;
    border-left: 1px solid var(--line-soft);
    box-sizing: border-box;
  }

  .page-about .about-rail__link[aria-current="true"] {
    border-left: 2px solid var(--copper-bright);
    background: transparent;
    color: var(--copper-bright);
  }

  .page-about .about-rail__link[aria-current="true"] .about-rail__no {
    color: var(--copper-bright);
  }

  .page-about .about-rail__cta {
    display: block;
  }

  .page-about .review-flow__body {
    padding-left: 46px;
  }
}

@media (min-width: 1024px) {
  .page-about .data-strip {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .team-grid {
    gap: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .team-filter__label,
  .page-about .review-flow__item summary,
  .page-about .about-rail__cta {
    transition: none;
  }
}