.page-about {
  --about-rail: 248px;
  --about-shadow: 7px 7px 0 rgba(11, 94, 90, 0.28);
}

.page-about .about-hero {
  display: grid;
  gap: 28px;
  padding-block: clamp(20px, 4vw, 44px) clamp(24px, 4vw, 40px);
}

.page-about .about-hero__title {
  margin: 10px 0 16px;
  font-family: var(--font-display);
  font-size: clamp(28px, 5.2vw, 48px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--text);
  max-width: 22ch;
}

.page-about .about-hero__text {
  margin: 0;
  max-width: 54ch;
  font-size: clamp(15px, 1.9vw, 17px);
  line-height: 1.75;
  color: var(--text-soft);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-hero__seal {
  position: relative;
  padding: 20px 18px 18px;
  border: 1px solid var(--line);
  background: linear-gradient(160deg, var(--surface) 0%, var(--ink-900) 100%);
  box-shadow: var(--about-shadow);
}

.page-about .about-hero__seal-label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--iron);
}

.page-about .about-hero__seal-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(56px, 13vw, 104px);
  line-height: 0.94;
  letter-spacing: -0.03em;
  color: var(--accent);
}

.page-about .about-hero__seal-note {
  margin: 10px 0 18px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--text-soft);
  max-width: 40ch;
}

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

.page-about .figure__media {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line-strong);
  background:
    repeating-linear-gradient(0deg, rgba(111, 124, 134, 0.16) 0 1px, transparent 1px 36px),
    repeating-linear-gradient(90deg, rgba(111, 124, 134, 0.16) 0 1px, transparent 1px 36px),
    var(--ink-800);
}

.page-about .figure__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.82) contrast(1.05);
}

.page-about .figure__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--text-dim);
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-bottom: clamp(24px, 4vw, 44px);
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stats__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 14px;
  background: var(--surface);
}

.page-about .about-stats__num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3.4vw, 30px);
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-stats__key {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--text-dim);
}

.page-about .archive {
  display: grid;
  gap: 26px;
  padding-bottom: clamp(40px, 6vw, 76px);
}

.page-about .rail-card {
  padding: 16px;
  border: 1px solid var(--line);
  background: var(--surface);
  box-shadow: var(--about-shadow);
}

.page-about .rail-card__sign {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  letter-spacing: 0.02em;
  color: var(--text);
}

.page-about .rail-card__sub {
  margin: 6px 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--iron);
}

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

.page-about .rail-link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 8px;
  border-left: 2px solid transparent;
  color: var(--text-soft);
  font-size: 14px;
  text-decoration: none;
  transition: color 0.16s ease, border-color 0.16s ease, background-color 0.16s ease;
}

.page-about .rail-link__num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--iron);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--accent);
  border-left-color: var(--accent);
  background: rgba(57, 242, 208, 0.07);
  outline: none;
}

.page-about .about-sec {
  scroll-margin-top: calc(var(--header-h) + 18px);
  padding-block: clamp(24px, 3.6vw, 40px);
  border-top: 1px solid var(--line);
}

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

.page-about .about-sec__head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 20px;
}

.page-about .about-sec__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: clamp(24px, 4vw, 36px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: rgba(57, 242, 208, 0.42);
}

.page-about .about-sec__title {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-size: clamp(20px, 3.4vw, 29px);
  line-height: 1.28;
  letter-spacing: -0.01em;
  color: var(--text);
  max-width: 30ch;
}

.page-about .about-sec__lead {
  max-width: 62ch;
  margin: 0 0 20px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-soft);
}

.page-about .about-sec__grid {
  display: grid;
  gap: 20px;
}

.page-about .about-sec__paper {
  padding: 20px 18px;
  border: 1px solid var(--line);
  background: var(--card);
  box-shadow: var(--about-shadow);
}

.page-about .about-sec__paper p {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--text-soft);
}

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

.page-about .about-sec__aside {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 18px;
  border: 1px solid var(--line);
  background: var(--bg);
}

.page-about .about-sec__note {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--text-dim);
}

.page-about .tag-row,
.page-about .tag-wall {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .text-link {
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid rgba(57, 242, 208, 0.42);
  padding-bottom: 2px;
}

.page-about .text-link:hover,
.page-about .text-link:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--paper);
  outline: none;
}

/* 发展年轮 */
.page-about .history-wrap {
  display: grid;
  gap: 24px;
}

.page-about .tl {
  margin: 4px 0 0;
  padding: 0 0 0 22px;
  list-style: none;
  border-left: 1px solid var(--line-strong);
}

.page-about .tl__item {
  position: relative;
  padding-bottom: 20px;
}

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

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 7px;
  width: 9px;
  height: 9px;
  background: var(--bg);
  border: 2px solid var(--accent);
}

.page-about .tl__year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .tl__name {
  margin: 4px 0 10px;
  font-size: 14px;
  color: var(--accent);
  letter-spacing: 0.04em;
}

.page-about .folio {
  border: 1px solid var(--line);
  background: var(--surface);
}

.page-about .folio summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 12px;
  cursor: pointer;
  font-size: 13px;
  color: var(--text-soft);
  list-style: none;
}

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

.page-about .folio summary::after {
  content: "＋";
  font-family: var(--font-mono);
  color: var(--accent);
}

.page-about .folio[open] summary::after {
  content: "－";
}

.page-about .folio summary:hover {
  color: var(--paper);
}

.page-about .folio__text {
  margin: 0;
  padding: 0 12px 14px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-dim);
}

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

/* 团队 */
.page-about .team-grid {
  display: grid;
  gap: 12px;
  margin-bottom: 22px;
}

.page-about .team-card {
  border: 1px solid var(--line);
  background: var(--card);
  box-shadow: 5px 5px 0 rgba(11, 94, 90, 0.22);
}

.page-about .team-card__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 13px 14px;
  cursor: pointer;
  list-style: none;
}

.page-about .team-card__head::-webkit-details-marker {
  display: none;
}

.page-about .team-card__role {
  font-family: var(--font-display);
  font-size: 16px;
  color: var(--text);
  letter-spacing: 0.01em;
}

.page-about .team-card__count {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--accent);
  border: 1px solid rgba(57, 242, 208, 0.4);
  padding: 2px 8px;
}

.page-about .team-card__body {
  padding: 0 14px 14px;
  border-top: 1px solid var(--line);
}

.page-about .team-card__body p {
  margin: 12px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-soft);
}

/* 方法四步 */
.page-about .steps {
  display: grid;
  gap: 1px;
  margin: 0 0 20px;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .steps__item {
  display: flex;
  gap: 14px;
  padding: 16px 14px;
  background: var(--surface);
}

.page-about .steps__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  padding-top: 3px;
}

.page-about .steps__title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 16px;
  letter-spacing: 0.01em;
  color: var(--text);
}

.page-about .steps__body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-soft);
}

.page-about .method-note {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 16px 18px;
  border-left: 3px solid var(--amber);
  background: rgba(255, 138, 61, 0.07);
}

.page-about .method-note p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-soft);
}

/* 服务对象 */
.page-about .user-grid {
  display: grid;
  gap: 12px;
  margin-bottom: 24px;
}

.page-about .user-card {
  padding: 16px 16px 18px;
  border: 1px solid var(--line);
  background: var(--bg);
  border-top: 2px solid rgba(57, 242, 208, 0.5);
}

.page-about .user-card__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 16px;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .user-card__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-soft);
}

/* 出口面板 */
.page-about .exit-panel {
  display: grid;
  gap: 18px;
  padding: 22px 20px;
  border: 1px solid var(--line-strong);
  background:
    linear-gradient(120deg, rgba(22, 58, 82, 0.92), rgba(7, 19, 31, 0.96)),
    var(--card);
  box-shadow: var(--about-shadow);
}

.page-about .exit-panel__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 19px;
  letter-spacing: 0.01em;
  color: var(--paper);
}

.page-about .exit-panel__desc {
  margin: 0;
  max-width: 58ch;
  font-size: 14px;
  line-height: 1.78;
  color: var(--text-soft);
}

.page-about .exit-panel__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

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

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

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

  .page-about .exit-panel {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }

  .page-about .exit-panel__actions {
    flex-direction: column;
    align-items: stretch;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    align-items: start;
    gap: 40px;
  }

  .page-about .about-sec__grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    gap: 24px;
    align-items: start;
  }

  .page-about .history-wrap {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }

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

@media (min-width: 1024px) {
  .page-about .archive {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .archive-rail {
    position: sticky;
    top: calc(var(--header-h) + 20px);
  }

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

  .page-about .user-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .page-about .user-card {
    grid-column: span 2;
  }

  .page-about .user-card:nth-child(4),
  .page-about .user-card:nth-child(5) {
    grid-column: span 3;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail-link,
  .page-about .text-link {
    transition: none;
  }
}