.page-about {
  --about-rail: 210px;
  --about-gap: clamp(24px, 4vw, 56px);
  --about-card-bg: rgba(20, 90, 68, 0.28);
  --about-card-bg-deep: rgba(7, 42, 32, 0.66);
  background: var(--c-green-night);
  color: var(--c-paper);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  background:
    radial-gradient(circle at 84% 10%, rgba(212, 175, 55, 0.14), transparent 56%),
    linear-gradient(168deg, var(--c-green) 0%, var(--c-green-night) 82%);
  border-bottom: 1px solid var(--line-gold);
  position: relative;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(90deg, var(--line-soft) 0 1px, transparent 1px 72px),
    repeating-linear-gradient(0deg, var(--line-soft) 0 1px, transparent 1px 72px);
  opacity: 0.35;
  pointer-events: none;
}

.page-about .hero-inner {
  position: relative;
  display: grid;
  gap: 32px;
  padding: clamp(28px, 5vw, 56px) 0 clamp(36px, 6vw, 76px);
}

.page-about .hero-h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 6vw, 3.5rem);
  line-height: 1.14;
  letter-spacing: 0.01em;
  margin: 14px 0 0;
  color: var(--c-paper);
  text-wrap: balance;
}

.page-about .hero-lede {
  margin: 20px 0 0;
  max-width: 36em;
  font-size: var(--fs-16);
  line-height: 1.85;
  color: var(--c-mist);
}

.page-about .hero-stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin: 28px 0 0;
  padding: 0;
  border-top: 1px solid var(--line-mid);
  padding-top: 18px;
}

.page-about .hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .hs-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.25rem, 3.4vw, 1.75rem);
  color: var(--c-gold);
  line-height: 1.1;
}

.page-about .hs-label {
  font-size: var(--fs-12);
  color: var(--c-mist);
  line-height: 1.5;
}

.page-about .hero-figure {
  margin: 0;
  border-left: 2px solid var(--c-gold);
  padding-left: 12px;
}

/* ---------- 主体双栏 ---------- */
.page-about .about-layout {
  display: grid;
  gap: 32px;
  padding: clamp(32px, 5vw, 64px) 0 clamp(48px, 8vw, 96px);
}

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

.page-about .rail-title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--c-gold);
  text-transform: uppercase;
}

.page-about .rail-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
}

.page-about .rail-link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 12px;
  font-size: var(--fs-14);
  color: var(--c-mist);
  text-decoration: none;
  border: 1px solid var(--line-soft);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .rail-num {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  color: var(--c-gold-dark);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--c-paper);
  border-color: var(--line-gold);
  background: rgba(212, 175, 55, 0.08);
}

.page-about .rail-link.is-active {
  color: var(--c-paper);
  border-color: var(--c-gold);
  background: rgba(212, 175, 55, 0.12);
}

.page-about .rail-link.is-active .rail-num {
  color: var(--c-gold);
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  margin-bottom: clamp(44px, 7vw, 84px);
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .about-section:last-child {
  margin-bottom: 0;
}

.page-about .sec-head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 10px 14px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line-soft);
  position: relative;
}

.page-about .sec-head::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 56px;
  height: 2px;
  background: var(--c-gold);
}

.page-about .sec-num {
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  letter-spacing: 0.1em;
  color: var(--c-gold);
}

.page-about .sec-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 3.4vw, 2.1rem);
  line-height: 1.25;
  color: var(--c-paper);
}

.page-about .sec-text {
  margin: 18px 0 0;
  max-width: 46em;
  font-size: var(--fs-16);
  line-height: 1.85;
  color: var(--c-mist);
}

.page-about .sub-title {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: var(--fs-18);
  letter-spacing: 0.02em;
  color: var(--c-paper);
}

.page-about .origin-quote {
  margin: 24px 0 0;
  border-left: 3px solid var(--c-red);
  background: linear-gradient(100deg, rgba(200, 16, 46, 0.12), transparent 70%);
  padding: 16px 18px;
}

.page-about .origin-quote p {
  margin: 0;
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--c-paper);
}

/* ---------- 内容体系卡片 ---------- */
.page-about .content-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 26px;
}

.page-about .c-card {
  background: linear-gradient(160deg, var(--about-card-bg), var(--about-card-bg-deep));
  border: 1px solid var(--line-soft);
  padding: 20px 18px 22px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: border-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .c-card:hover {
  border-color: var(--line-gold);
  transform: translateY(-2px);
}

.page-about .c-card--focus {
  border-color: var(--line-gold);
  box-shadow: inset 0 0 0 1px rgba(212, 175, 55, 0.18);
}

.page-about .c-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--fs-18);
  letter-spacing: 0.02em;
  color: var(--c-paper);
}

.page-about .c-desc {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--c-mist);
}

.page-about .c-meta {
  margin: auto 0 0;
  padding-top: 10px;
  border-top: 1px dashed var(--line-soft);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  line-height: 1.6;
  color: var(--c-gold-dark);
}

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

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--c-gold), rgba(201, 216, 208, 0.18));
}

.page-about .tl-item {
  position: relative;
  padding-left: 30px;
  margin-bottom: 12px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 15px;
  width: 13px;
  height: 13px;
  border: 1px solid var(--c-gold);
  background: var(--c-green-night);
  transform: rotate(45deg);
}

.page-about .tl-node {
  border: 1px solid var(--line-soft);
  background: var(--about-card-bg-deep);
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .tl-node[open] {
  border-color: var(--line-gold);
  background: var(--about-card-bg);
}

.page-about .tl-summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 13px 14px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .tl-summary:focus-visible {
  outline: 2px solid var(--c-gold);
  outline-offset: 2px;
}

.page-about .tl-year {
  flex: none;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--fs-14);
  color: var(--c-paper);
  background: var(--c-red);
  padding: 2px 8px;
  letter-spacing: 0.04em;
}

.page-about .tl-head {
  flex: 1;
  font-size: var(--fs-16);
  font-weight: 700;
  line-height: 1.5;
  color: var(--c-paper);
}

.page-about .tl-chev {
  flex: none;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--c-gold);
  border-bottom: 2px solid var(--c-gold);
  transform: rotate(45deg);
  transition: transform 0.25s var(--ease);
}

.page-about .tl-node[open] .tl-chev {
  transform: rotate(-135deg);
}

.page-about .tl-body {
  padding: 0 14px 16px;
}

.page-about .tl-body p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.85;
  color: var(--c-mist);
}

/* ---------- 团队 ---------- */
.page-about .team-bars {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-top: 26px;
}

.page-about .team-bar {
  border: 1px solid var(--line-soft);
  border-left: 3px solid var(--c-gold);
  background: var(--about-card-bg-deep);
  padding: 16px 14px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  transition: background 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .team-bar:hover {
  background: var(--about-card-bg);
  border-color: var(--line-gold);
  border-left-color: var(--c-red);
}

.page-about .tb-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--fs-32);
  line-height: 1;
  color: var(--c-gold);
}

.page-about .tb-label {
  font-size: var(--fs-14);
  font-weight: 700;
  color: var(--c-paper);
}

.page-about .tb-desc {
  margin: 4px 0 0;
  font-size: var(--fs-12);
  line-height: 1.7;
  color: var(--c-mist);
}

.page-about .team-split {
  display: grid;
  gap: 24px;
  margin-top: 30px;
}

.page-about .review-flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .review-flow li {
  position: relative;
  padding: 14px 16px 14px 52px;
  border: 1px solid var(--line-soft);
  background: rgba(11, 61, 46, 0.4);
}

.page-about .rf-num {
  position: absolute;
  left: 14px;
  top: 14px;
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  color: var(--c-red);
  background: var(--c-paper);
  padding: 0 5px;
  line-height: 1.5;
}

.page-about .review-flow strong {
  display: block;
  font-size: var(--fs-16);
  color: var(--c-paper);
  margin-bottom: 4px;
}

.page-about .review-flow p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--c-mist);
}

.page-about .team-figure,
.page-about .eco-figure {
  margin: 0;
}

/* ---------- 合作生态 ---------- */
.page-about .eco-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin-top: 26px;
}

.page-about .eco-card {
  border: 1px solid var(--line-soft);
  border-top: 2px solid var(--c-red);
  background: var(--about-card-bg-deep);
  padding: 18px 16px 20px;
}

.page-about .eco-kicker {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--c-gold);
}

.page-about .eco-num {
  margin: 0;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.75rem, 5vw, 2.5rem);
  line-height: 1;
  color: var(--c-paper);
}

.page-about .eco-label {
  margin: 6px 0 0;
  font-size: var(--fs-14);
  font-weight: 700;
  color: var(--c-gold);
}

.page-about .eco-desc {
  margin: 10px 0 0;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--c-mist);
}

.page-about .eco-honor {
  margin-top: 18px;
  border: 1px solid var(--line-gold);
  background: linear-gradient(100deg, rgba(212, 175, 55, 0.12), transparent 78%);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .honor-badge {
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--c-ink);
  background: var(--c-gold);
  padding: 3px 9px;
}

.page-about .honor-text {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--c-paper);
}

.page-about .eco-figure {
  margin-top: 22px;
}

/* ---------- 联系 ---------- */
.page-about .contact-board {
  display: grid;
  gap: 22px;
  margin-top: 24px;
  border: 1px solid var(--line-soft);
  border-top: 2px solid var(--c-gold);
  background: linear-gradient(160deg, var(--about-card-bg), var(--about-card-bg-deep));
  padding: clamp(20px, 4vw, 32px);
}

.page-about .contact-copy .sec-text {
  margin-top: 0;
}

.page-about .contact-legal {
  margin: 14px 0 18px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  color: var(--c-mist);
}

.page-about .contact-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .contact-list li {
  display: grid;
  gap: 2px;
  padding: 10px 0;
  border-bottom: 1px dashed var(--line-soft);
}

.page-about .contact-list li:last-child {
  border-bottom: 0;
}

.page-about .contact-tip {
  margin: 14px 0 0;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--c-amber);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .content-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .contact-list li {
    grid-template-columns: 96px minmax(0, 1fr);
    align-items: baseline;
    gap: 12px;
  }
}

@media (min-width: 720px) {
  .page-about .team-bars {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .hero-inner {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    align-items: center;
    gap: 48px;
  }

  .page-about .team-split {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
    gap: 32px;
  }

  .page-about .contact-board {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: 32px;
    align-items: start;
  }
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 24px);
    border-top: 0;
    border-left: 1px solid var(--line-mid);
    padding-top: 0;
    padding-left: 16px;
  }

  .page-about .rail-list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
  }

  .page-about .rail-link {
    border: 0;
    border-left: 2px solid transparent;
    padding: 7px 10px;
    background: transparent;
  }

  .page-about .rail-link:hover,
  .page-about .rail-link:focus-visible {
    background: rgba(212, 175, 55, 0.08);
  }

  .page-about .rail-link.is-active {
    border-left-color: var(--c-gold);
    background: rgba(212, 175, 55, 0.1);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .c-card,
  .page-about .tl-chev,
  .page-about .rail-link,
  .page-about .team-bar {
    transition: none;
  }

  .page-about .c-card:hover {
    transform: none;
  }
}