.page-about {
  --about-skew: 44px;
  --about-gap: 20px;
  --about-title-color: var(--ice);
  background: var(--ink);
  color: var(--ice);
  font-family: var(--font-body);
}

/* ---------- 面包屑与首屏 ---------- */
.page-about .about-crumbs {
  margin-bottom: 18px;
}

.page-about .breadcrumbs {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.page-about .breadcrumbs a {
  color: var(--cyan);
  text-decoration: none;
  transition: color var(--t-fast);
}

.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--ice);
  text-decoration: underline;
}

.page-about .about-hero {
  position: relative;
  padding: 26px 0 52px;
  background:
    radial-gradient(circle at 86% 8%, rgba(43, 224, 208, 0.16), transparent 58%),
    linear-gradient(158deg, var(--ink) 0%, var(--ink-deep) 100%);
}

.page-about .about-hero-grid {
  display: grid;
  gap: 30px;
  align-items: end;
}

.page-about .about-title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(38px, 9vw, 88px);
  line-height: 0.94;
  letter-spacing: -0.02em;
  color: var(--about-title-color);
}

.page-about .about-lede {
  margin: 20px 0 0;
  max-width: 48ch;
  font-size: 16px;
  line-height: 1.78;
  color: rgba(247, 250, 252, 0.78);
}

.page-about .about-hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin: 26px 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.page-about .about-hero-stats > div {
  min-width: 0;
}

.page-about .about-stat-key {
  display: block;
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .about-stat-num {
  margin: 6px 0 0;
  font-size: clamp(19px, 4.6vw, 27px);
  font-weight: 500;
  color: var(--cyan);
  letter-spacing: -0.01em;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-hero-figure {
  margin: 0;
  align-self: stretch;
}

.page-about .about-hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

/* ---------- 章节通用头部 ---------- */
.page-about .about-sec-head {
  display: grid;
  gap: 10px;
  margin-bottom: 28px;
}

.page-about .about-sec-num {
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--lava);
}

.page-about .about-sec-title {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(24px, 5.4vw, 38px);
  line-height: 1.22;
  color: var(--about-title-color);
}

.page-about .about-sec-sub {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(247, 250, 252, 0.72);
}

/* ---------- 01 三条主线 ---------- */
.page-about .about-claim {
  padding: 52px 0 56px;
  background: var(--ink-deep);
}

.page-about .about-claim-grid {
  display: grid;
  gap: 14px;
}

.page-about .about-claim-card {
  padding: 22px 20px 20px;
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(43, 52, 64, 0.55), rgba(11, 27, 51, 0.55));
  box-shadow: inset 0 1px 0 rgba(43, 224, 208, 0.22);
  transition: border-color var(--t-fast), transform var(--t-fast);
}

.page-about .about-claim-card:hover {
  border-color: var(--cyan);
  transform: translateY(-2px);
}

.page-about .about-claim-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 600;
  color: var(--ice);
}

.page-about .about-claim-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
  color: rgba(247, 250, 252, 0.76);
}

.page-about .about-claim-note {
  margin-top: 14px !important;
  padding-top: 12px;
  border-top: 1px dashed var(--line-strong);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--cyan) !important;
}

/* ---------- 02 发展历程 ---------- */
.page-about .about-history {
  padding: 52px 0 76px;
  background: var(--ink-brown);
}

.page-about .about-history-paper {
  margin: 0 0 30px;
  overflow: hidden;
  border: 1px solid var(--line);
}

.page-about .about-history-paper img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 150px;
  object-fit: cover;
  opacity: 0.72;
}

.page-about .about-timeline {
  display: grid;
  gap: 26px;
}

.page-about .about-years {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  scrollbar-width: thin;
}

.page-about .about-year {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  font-size: 13px;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--t-fast), border-color var(--t-fast), background var(--t-fast);
}

.page-about .about-year::before {
  content: "";
  width: 7px;
  height: 7px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--graphite);
  border: 1px solid var(--mist);
  transition: background var(--t-fast), border-color var(--t-fast), box-shadow var(--t-fast);
}

.page-about .about-year:hover,
.page-about .about-year:focus-visible {
  color: var(--cyan);
  border-color: var(--line-strong);
  background: rgba(43, 224, 208, 0.07);
}

.page-about .about-year:hover::before,
.page-about .about-year:focus-visible::before {
  background: var(--cyan);
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(43, 224, 208, 0.16);
}

.page-about .about-events {
  display: grid;
  gap: 0;
}

.page-about .about-event {
  position: relative;
  padding: 0 0 26px 22px;
  border-left: 1px solid var(--line-strong);
  scroll-margin-top: calc(var(--header-h) + 26px);
}

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

.page-about .about-event::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 8px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--graphite);
  border: 1px solid var(--mist);
  transition: background var(--t-fast), border-color var(--t-fast);
}

.page-about .about-event:target {
  border-left-color: var(--cyan);
}

.page-about .about-event:target::before {
  background: var(--cyan);
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(43, 224, 208, 0.16);
}

.page-about .about-event-year {
  margin: 0 0 6px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--lava);
}

.page-about .about-event:target .about-event-year {
  color: var(--cyan);
}

.page-about .about-event h3 {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-size: 19px;
  font-weight: 600;
  line-height: 1.35;
  color: var(--ice);
}

.page-about .about-event > p {
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
  color: rgba(247, 250, 252, 0.74);
}

.page-about .about-event details {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px dashed var(--line);
}

.page-about .about-event summary {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  list-style: none;
  font-size: 13px;
  letter-spacing: 0.03em;
  color: var(--cyan);
  transition: color var(--t-fast);
}

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

.page-about .about-event summary::before {
  content: "+";
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--lava);
}

.page-about .about-event details[open] summary::before {
  content: "–";
}

.page-about .about-event summary:hover {
  color: var(--ice);
}

.page-about .about-event details p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(247, 250, 252, 0.68);
}

/* ---------- 奶油纸区块 ---------- */
.page-about .about-sheet {
  position: relative;
  margin-top: calc(var(--about-skew) * -1);
  padding: calc(var(--about-skew) + 58px) 0 8px;
  background: var(--paper);
  color: var(--ink-brown);
  clip-path: polygon(0 var(--about-skew), 100% 0, 100% 100%, 0 100%);
}

.page-about .about-sheet .about-sec-num {
  color: var(--press);
}

.page-about .about-sheet .about-sec-title {
  color: var(--ink-brown);
}

.page-about .about-sheet .about-sec-sub {
  color: rgba(26, 18, 14, 0.74);
}

/* ---------- 03 团队分工 ---------- */
.page-about .about-team {
  padding-bottom: 52px;
}

.page-about .about-team-grid {
  display: grid;
  gap: 24px;
}

.page-about .about-team-figure {
  margin: 0;
  box-shadow: 6px 6px 0 rgba(26, 18, 14, 0.14);
}

.page-about .about-team-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-team-cards {
  display: grid;
  gap: 12px;
}

.page-about .about-team-card {
  padding: 18px 18px 20px;
  background: rgba(255, 255, 255, 0.5);
  border: 1px solid var(--line-paper);
  border-left: 3px solid var(--press);
  transition: background var(--t-fast), border-color var(--t-fast);
}

.page-about .about-team-card:hover {
  background: rgba(255, 255, 255, 0.82);
  border-left-color: var(--lava);
}

.page-about .about-team-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 600;
  color: var(--ink-brown);
}

.page-about .about-team-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: rgba(26, 18, 14, 0.78);
}

.page-about .about-team-flow {
  margin: 26px 0 0;
  padding: 16px 18px;
  border: 1px dashed rgba(26, 18, 14, 0.3);
  background: rgba(255, 255, 255, 0.42);
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(26, 18, 14, 0.82);
}

/* ---------- 04 数据校对 ---------- */
.page-about .about-audit {
  padding: 46px 0 52px;
  border-top: 1px solid var(--line-paper);
}

.page-about .about-audit-grid {
  display: grid;
  gap: 26px;
}

.page-about .about-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 18px;
}

.page-about .about-steps li {
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr);
  column-gap: 12px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line-paper);
}

.page-about .about-steps li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-step-num {
  grid-row: span 2;
  font-size: 15px;
  font-weight: 500;
  color: var(--press);
  padding-top: 2px;
}

.page-about .about-steps h3 {
  margin: 0 0 6px;
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 600;
  color: var(--ink-brown);
}

.page-about .about-steps p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: rgba(26, 18, 14, 0.76);
}

.page-about .about-audit-note {
  padding: 24px 20px;
  background: var(--ink-brown);
  color: var(--ice);
  border-bottom: 4px solid var(--lava);
}

.page-about .about-note-num {
  margin: 0;
  font-size: clamp(40px, 11vw, 64px);
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-note-text {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.76;
  color: rgba(247, 250, 252, 0.82);
}

.page-about .about-note-small {
  margin: 14px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 05 服务承诺 ---------- */
.page-about .about-promise {
  padding: 46px 0 60px;
  border-top: 1px solid var(--line-paper);
}

.page-about .about-promise-grid {
  display: grid;
  gap: 12px;
}

.page-about .about-promise-card {
  padding: 20px 18px 22px;
  background: rgba(255, 255, 255, 0.5);
  border: 1px solid var(--line-paper);
  border-top: 3px solid var(--ink-brown);
  transition: border-top-color var(--t-fast), background var(--t-fast);
}

.page-about .about-promise-card:hover {
  border-top-color: var(--lava);
  background: rgba(255, 255, 255, 0.84);
}

.page-about .about-promise-num {
  margin: 0 0 10px;
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--press);
}

.page-about .about-promise-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-size: 17px;
  font-weight: 600;
  color: var(--ink-brown);
}

.page-about .about-promise-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.74;
  color: rgba(26, 18, 14, 0.76);
}

/* ---------- 06 运营与备案 ---------- */
.page-about .about-ops {
  padding: 54px 0 56px;
  background:
    linear-gradient(180deg, var(--ink-deep) 0%, var(--ink) 100%);
}

.page-about .about-ops-grid {
  display: grid;
  gap: 30px;
}

.page-about .about-ops-lede {
  margin: 14px 0 0;
  max-width: 52ch;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(247, 250, 252, 0.74);
}

.page-about .about-ops-list {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.page-about .about-ops-list li {
  display: grid;
  gap: 4px;
  padding: 13px 0;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
  color: var(--ice);
  word-break: break-word;
}

.page-about .about-ops-key {
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--mist);
}

.page-about .about-ops-list a {
  color: var(--cyan);
  text-decoration: none;
  transition: color var(--t-fast), border-color var(--t-fast);
  border-bottom: 1px solid transparent;
}

.page-about .about-ops-list a:hover,
.page-about .about-ops-list a:focus-visible {
  color: var(--ice);
  border-bottom-color: var(--cyan);
}

.page-about .about-ops-copy .btn {
  margin-top: 24px;
}

.page-about .about-ops-meta {
  display: grid;
  gap: 12px;
  align-content: start;
}

.page-about .about-ops-card {
  padding: 18px;
  border: 1px solid var(--line-strong);
  background: rgba(43, 52, 64, 0.4);
}

.page-about .about-ops-card-title {
  margin: 0 0 8px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--lava);
}

.page-about .about-ops-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: rgba(247, 250, 252, 0.78);
}

/* ---------- 尾部指引 ---------- */
.page-about .about-next {
  padding: 0 0 56px;
  background: var(--ink);
}

.page-about .about-next-label {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--mist);
}

.page-about .about-next-links {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-next-links a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 18px;
  background: var(--ink-deep);
  color: var(--ice);
  font-size: 15px;
  text-decoration: none;
  transition: background var(--t-fast), color var(--t-fast);
}

.page-about .about-next-links a span {
  color: var(--lava);
  font-family: var(--font-mono);
}

.page-about .about-next-links a:hover,
.page-about .about-next-links a:focus-visible {
  background: var(--graphite);
  color: var(--cyan);
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 700px) {
  .page-about .about-claim-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

@media (min-width: 860px) {
  .page-about {
    --about-skew: 72px;
  }

  .page-about .about-hero {
    padding: 34px 0 68px;
  }

  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    gap: 46px;
  }

  .page-about .about-claim {
    padding: 64px 0 68px;
  }

  .page-about .about-history {
    padding: 64px 0 96px;
  }

  .page-about .about-history-paper img {
    max-height: 190px;
  }

  .page-about .about-timeline {
    grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
    gap: 42px;
    align-items: start;
  }

  .page-about .about-years {
    position: sticky;
    top: calc(var(--header-h) + 20px);
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0;
    border-bottom: 0;
    border-left: 1px solid var(--line-strong);
  }

  .page-about .about-year {
    border: 0;
    border-left: 2px solid transparent;
    margin-left: -1px;
    padding: 15px 0 15px 18px;
    font-size: 14px;
  }

  .page-about .about-year:hover,
  .page-about .about-year:focus-visible {
    background: transparent;
    border-left-color: var(--cyan);
  }

  .page-about .about-event {
    padding-left: 28px;
  }

  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .about-audit-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 38px;
    align-items: start;
  }

  .page-about .about-promise-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-ops-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-ops-list li {
    grid-template-columns: 108px minmax(0, 1fr);
    align-items: baseline;
    gap: 16px;
  }
}

@media (min-width: 1120px) {
  .page-about .about-lede {
    font-size: 17px;
  }

  .page-about .about-sec-sub {
    font-size: 16px;
  }

  .page-about .about-claim-card {
    padding: 26px 24px 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0ms !important;
  }

  .page-about .about-claim-card:hover {
    transform: none;
  }
}
</main>