.page-about {
  --about-accent: var(--spring);
  --about-panel: var(--sand);
  background: var(--paper);
  color: var(--ink);
  overflow-x: hidden;
}

.page-about h2 {
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 40px);
  line-height: 1.25;
  letter-spacing: 0.02em;
  margin: 0;
  color: var(--ink);
}

.page-about h3 {
  font-family: var(--font-display);
  font-size: 19px;
  line-height: 1.4;
  letter-spacing: 0.01em;
  margin: 8px 0 8px;
  color: var(--ink);
}

.page-about .note {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-70);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: 116px 0 clamp(36px, 6vw, 72px);
  background:
    repeating-linear-gradient(90deg, rgba(28, 27, 23, 0.035) 0 1px, transparent 1px 96px),
    var(--paper);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 32px;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(30px, 6.6vw, 62px);
  font-weight: 800;
  line-height: 1.14;
  letter-spacing: 0.02em;
  margin: 14px 0 18px;
  color: var(--ink);
  max-width: 16em;
}

.page-about .about-hero__intro {
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-70);
  margin: 0 0 14px;
  max-width: 36em;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-about .about-hero__figure {
  position: relative;
  background: var(--sand);
  padding: 24px 20px 20px;
  border-top: 3px solid var(--spring);
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 0 100%);
}

.page-about .about-figure__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--ink-55);
  margin: 0;
}

.page-about .about-figure__value {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(76px, 20vw, 132px);
  line-height: 0.86;
  letter-spacing: -0.01em;
  margin: 6px 0 4px;
  color: var(--ink);
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.page-about .about-figure__unit {
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--ink-70);
}

.page-about .about-roles {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-roles__item {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 9px 0 12px;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-roles__item--spring { --season: var(--spring); --bar: 100%; }
.page-about .about-roles__item--summer { --season: var(--summer); --bar: 82%; }
.page-about .about-roles__item--autumn { --season: var(--autumn); --bar: 73%; }

.page-about .about-roles__num {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
  min-width: 2ch;
}

.page-about .about-roles__name {
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--ink-70);
}

.page-about .about-roles__bar {
  position: absolute;
  left: 0;
  bottom: -1px;
  height: 3px;
  width: var(--bar);
  background: var(--season);
}

.page-about .about-figure__cap {
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-70);
  margin: 16px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

/* ---------- 目录条 ---------- */
.page-about .about-index {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}

.page-about .about-index__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 18px;
  padding: 13px 0;
}

.page-about .about-index__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--ink-55);
  white-space: nowrap;
}

.page-about .about-index__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 6px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-index__link {
  display: inline-block;
  padding: 5px 12px;
  font-size: 13px;
  color: var(--ink-70);
  text-decoration: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  transition: color var(--t), border-color var(--t), background-color var(--t);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--ink);
  border-color: var(--ink);
  background: var(--sand);
}

.page-about .about-index__link:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

/* ---------- 团队分工 ---------- */
.page-about .about-team__grid {
  display: grid;
  gap: 32px;
  margin-top: 28px;
}

.page-about .about-team__lead {
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-70);
  margin: 0;
  max-width: 40em;
}

.page-about .about-role-cards {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-role-card {
  --season: var(--spring);
  position: relative;
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 18px 18px 16px;
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
  transition: transform var(--t), border-color var(--t), background-color var(--t);
}

.page-about .about-role-card--spring { --season: var(--spring); }
.page-about .about-role-card--summer { --season: var(--summer); }
.page-about .about-role-card--autumn { --season: var(--autumn); }

.page-about .about-role-card::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 4px;
  height: 100%;
  background: var(--season);
}

.page-about .about-role-card:hover,
.page-about .about-role-card:focus-within {
  transform: translateY(-3px);
  border-color: var(--season);
  background: var(--sand);
}

.page-about .about-role-card__meta {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink-55);
  margin: 0;
}

.page-about .about-role-card__num {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .about-role-card p:last-child {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-70);
  margin: 0;
}

.page-about .about-team__side {
  display: grid;
  gap: 18px;
}

.page-about .about-team__media {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--sand);
  padding: 10px;
}

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

.page-about .media__cap {
  font-size: 12px;
  line-height: 1.6;
  color: var(--ink-55);
  margin: 10px 0 0;
  padding-left: 10px;
  border-left: 2px solid var(--spring);
}

.page-about .about-team__side .note {
  border-left: 1px solid var(--line);
  padding-left: 14px;
  margin: 0;
}

/* ---------- 内容方法（深色章） ---------- */
.page-about .about-method {
  background: var(--ink);
  color: var(--paper);
}

.page-about .about-method .eyebrow {
  color: var(--summer);
}

.page-about .about-method h2 {
  color: var(--paper);
}

.page-about .about-method__grid {
  display: grid;
  gap: 26px;
  margin-top: 28px;
}

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

.page-about .about-season {
  --season: var(--spring);
  border-top: 3px solid var(--season);
  background: var(--ink-2);
  padding: 16px 16px 18px;
}

.page-about .about-season--spring { --season: var(--spring); }
.page-about .about-season--summer { --season: var(--summer); }
.page-about .about-season--autumn { --season: var(--autumn); }
.page-about .about-season--winter { --season: var(--winter); }

.page-about .about-season__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--season);
  margin: 0;
}

.page-about .about-method .about-season h3 {
  color: var(--paper);
  font-size: 18px;
}

.page-about .about-season p:last-child {
  font-size: 14px;
  line-height: 1.75;
  color: var(--paper-80);
  margin: 0;
}

.page-about .about-method__media {
  margin: 0;
}

.page-about .about-method__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  border: 1px solid var(--line-light);
}

.page-about .about-method__media .media__cap {
  color: var(--paper-80);
  border-left-color: var(--winter);
}

.page-about .about-method__note {
  margin: 26px 0 0;
  padding-left: 16px;
  border-left: 2px solid var(--summer);
  font-size: 14px;
  line-height: 1.85;
  color: var(--paper-80);
  max-width: 62ch;
}

/* ---------- 发展历程 ---------- */
.page-about .about-history__grid {
  display: grid;
  gap: 30px;
  margin-top: 28px;
}

.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 28px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--spring) 0%, var(--spring) 22%, var(--summer) 40%, var(--autumn) 62%, var(--winter) 100%);
}

.page-about .about-timeline__item {
  --season: var(--spring);
  position: relative;
  padding: 0 0 24px;
  outline-offset: 6px;
}

.page-about .about-timeline__item--spring { --season: var(--spring); }
.page-about .about-timeline__item--summer { --season: var(--summer); }
.page-about .about-timeline__item--autumn { --season: var(--autumn); }
.page-about .about-timeline__item--winter { --season: var(--winter); }

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 8px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--season);
  box-shadow: 0 0 0 4px var(--sand);
}

.page-about .about-timeline__item:focus-visible {
  outline: 3px solid var(--focus);
}

.page-about .about-timeline__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--ink);
}

.page-about .about-timeline__item h3 {
  font-size: 17px;
  margin: 2px 0 6px;
}

.page-about .about-timeline__item p {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-70);
  margin: 0;
  max-width: 44em;
}

.page-about .about-timeline__more {
  margin-top: 6px;
  color: var(--ink-55);
  border-left: 1px solid var(--line);
  padding-left: 10px;
}

.page-about .about-history__aside {
  align-self: start;
  background: var(--paper);
  border: 1px solid var(--line);
  border-top: 3px solid var(--winter);
  padding: 20px 18px;
}

.page-about .about-history__aside-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--winter-deep);
  margin: 0 0 8px;
}

.page-about .about-history__aside p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-70);
  margin: 0 0 12px;
}

.page-about .about-textlink {
  display: inline-block;
  font-size: 14px;
  color: var(--winter-deep);
  text-decoration: none;
  border-bottom: 1px solid currentColor;
  padding-bottom: 2px;
}

.page-about .about-textlink:hover,
.page-about .about-textlink:focus-visible {
  color: var(--ink);
}

.page-about .about-textlink:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

/* ---------- 服务能力 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin: 28px 0 0;
}

.page-about .about-stat {
  background: var(--paper);
  padding: 18px 16px;
}

.page-about .about-stat dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--ink-55);
  margin-bottom: 6px;
}

.page-about .about-stat dd {
  margin: 0;
  font-size: 14px;
  color: var(--ink-70);
}

.page-about .about-stat__num {
  font-family: var(--font-display);
  font-size: clamp(28px, 6vw, 42px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.01em;
  color: var(--ink);
  margin-right: 2px;
}

.page-about .about-stat:nth-child(1) .about-stat__num { color: var(--spring-deep); }
.page-about .about-stat:nth-child(2) .about-stat__num { color: var(--summer-deep); }
.page-about .about-stat:nth-child(3) .about-stat__num { color: var(--autumn-deep); }
.page-about .about-stat:nth-child(4) .about-stat__num { color: var(--winter-deep); }

.page-about .about-capability__note {
  margin: 22px 0 0;
  padding-left: 16px;
  border-left: 2px solid var(--autumn);
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink-70);
  max-width: 62ch;
}

/* ---------- 合作生态 ---------- */
.page-about .about-partners__grid {
  display: grid;
  gap: 30px;
}

.page-about .about-partners__copy p:not(.eyebrow) {
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-70);
  margin: 16px 0 0;
  max-width: 40em;
}

.page-about .about-partner-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
}

.page-about .about-partner-tags li {
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--ink);
  background: var(--sand);
  border-left: 3px solid var(--spring);
  padding: 6px 12px;
}

.page-about .about-partner-tags li:nth-child(2) { border-left-color: var(--summer); }
.page-about .about-partner-tags li:nth-child(3) { border-left-color: var(--autumn); }
.page-about .about-partner-tags li:nth-child(4) { border-left-color: var(--winter); }

.page-about .about-partners__media {
  margin: 0;
  border: 1px solid var(--line);
  padding: 10px;
  background: var(--paper);
}

.page-about .about-partners__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 11 / 7;
  object-fit: cover;
  background: var(--sand);
}

.page-about .about-partners__media .media__cap {
  border-left-color: var(--autumn);
}

/* ---------- 联络条 ---------- */
.page-about .about-reach {
  position: relative;
  background: var(--ink);
  color: var(--paper);
  padding: clamp(40px, 7vw, 72px) 0 clamp(36px, 6vw, 56px);
}

.page-about .about-reach::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--spring) 0 25%, var(--summer) 25% 50%, var(--autumn) 50% 75%, var(--winter) 75% 100%);
}

.page-about .about-reach .eyebrow {
  color: var(--winter);
}

.page-about .about-reach h2 {
  color: var(--paper);
}

.page-about .about-reach__inner {
  display: grid;
  gap: 28px;
}

.page-about .about-reach__copy p:not(.eyebrow) {
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper-80);
  margin: 14px 0 0;
  max-width: 40em;
}

.page-about .about-reach__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-about .about-reach__facts {
  display: grid;
  gap: 1px;
  background: var(--line-light);
  border: 1px solid var(--line-light);
  margin: 0;
  align-self: start;
}

.page-about .about-reach__fact {
  background: var(--ink-2);
  padding: 14px 16px;
}

.page-about .about-reach__fact dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--winter);
  margin-bottom: 4px;
}

.page-about .about-reach__fact dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--paper);
  word-break: break-word;
}

.page-about .about-reach__links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  list-style: none;
  margin: 32px 0 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--line-light);
}

.page-about .about-reach__links a {
  font-size: 13px;
  color: var(--paper-80);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  padding-bottom: 2px;
  transition: color var(--t), border-color var(--t);
}

.page-about .about-reach__links a:hover,
.page-about .about-reach__links a:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

.page-about .about-reach__links a:focus-visible {
  outline: 3px solid var(--paper);
  outline-offset: 3px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-reach__facts {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: 7fr 5fr;
    gap: 56px;
    align-items: start;
  }

  .page-about .about-team__grid {
    grid-template-columns: 7fr 5fr;
    gap: 48px;
    align-items: start;
  }

  .page-about .about-method__grid {
    grid-template-columns: 7fr 5fr;
    gap: 40px;
    align-items: start;
  }

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

  .page-about .about-history__grid {
    grid-template-columns: 8fr 4fr;
    gap: 44px;
    align-items: start;
  }

  .page-about .about-partners__grid {
    grid-template-columns: 5fr 7fr;
    gap: 48px;
    align-items: center;
  }

  .page-about .about-reach__inner {
    grid-template-columns: 7fr 5fr;
    gap: 48px;
    align-items: start;
  }

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

  .page-about .about-stats {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}

@media (hover: hover) and (min-width: 900px) {
  .page-about .about-timeline__more {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height var(--t) ease, opacity var(--t) ease;
  }

  .page-about .about-timeline__item:hover .about-timeline__more,
  .page-about .about-timeline__item:focus-within .about-timeline__more,
  .page-about .about-timeline__item:focus .about-timeline__more {
    max-height: 180px;
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-role-card,
  .page-about .about-index__link,
  .page-about .about-timeline__more {
    transition: none;
  }
  .page-about .about-role-card:hover,
  .page-about .about-role-card:focus-within {
    transform: none;
  }
}