.page-about {
  --about-gap: clamp(24px, 4vw, 56px);
  --about-radius: clamp(20px, 2.6vw, 32px);
  --about-line: rgba(28, 27, 24, 0.12);
  position: relative;
  overflow-x: clip;
  background-color: var(--ivory);
  background-image: radial-gradient(rgba(28, 27, 24, 0.055) 1px, transparent 1.2px);
  background-size: 20px 20px;
  color: var(--graphite);
  font-family: var(--font-body);
  line-height: 1.75;
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

.page-about .section {
  padding: 0 0 clamp(44px, 6vw, 88px);
}

.page-about .h-section {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(26px, 4vw, 44px);
  font-weight: 600;
  line-height: 1.24;
  letter-spacing: 0.03em;
  color: var(--graphite);
}

.page-about .lede {
  margin: 14px 0 0;
  max-width: 56ch;
  font-size: clamp(15px, 1.35vw, 17px);
  line-height: 1.8;
  color: rgba(28, 27, 24, 0.8);
}

.page-about .note-card {
  margin-top: clamp(18px, 2.4vw, 28px);
  padding: 16px 20px;
  border-left: 3px solid var(--gold);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  background: rgba(228, 220, 203, 0.6);
  font-size: 13.5px;
  line-height: 1.78;
  color: rgba(28, 27, 24, 0.78);
}

.page-about .note-card a {
  color: var(--wine);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .note-card a:hover {
  color: var(--cinnabar);
}

/* 面包屑 */
.page-about .breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  padding-top: clamp(18px, 3vw, 30px);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--patina);
}

.page-about .breadcrumb a {
  color: var(--patina);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-about .breadcrumb a:hover {
  color: var(--cinnabar);
  border-bottom-color: currentColor;
}

.page-about .breadcrumb span[aria-current="page"] {
  color: var(--graphite);
}

/* 首屏 */
.page-about .about-hero {
  padding: clamp(28px, 4.5vw, 66px) 0 clamp(30px, 4vw, 62px);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  align-items: end;
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-size: clamp(38px, 7.4vw, 88px);
  font-weight: 400;
  line-height: 1.08;
  letter-spacing: 0.035em;
  color: var(--graphite);
  text-wrap: balance;
}

.page-about .about-hero__lede {
  margin-top: clamp(18px, 2.4vw, 28px);
  max-width: 48ch;
}

.page-about .about-hero__note {
  margin: 16px 0 0;
  max-width: 44ch;
  font-size: 14px;
  line-height: 1.8;
  color: var(--patina);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(22px, 3vw, 34px);
}

.page-about .about-hero__panel {
  position: relative;
  overflow: hidden;
  padding: clamp(24px, 3.4vw, 40px);
  border-radius: var(--about-radius);
  background: linear-gradient(155deg, var(--ink) 0%, #062b25 62%, var(--indigo) 135%);
  color: var(--ivory);
  box-shadow: var(--shadow-card);
}

.page-about .about-hero__panel::after {
  content: "";
  position: absolute;
  right: -32%;
  bottom: -46%;
  width: 260px;
  height: 260px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(201, 162, 39, 0.34), transparent 70%);
  pointer-events: none;
}

.page-about .about-hero__panel-k {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--celadon);
}

.page-about .about-hero__big {
  margin: 6px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(44px, 6.2vw, 64px);
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--gold);
}

.page-about .about-hero__panel-unit {
  margin: 8px 0 0;
  font-size: 13.5px;
  letter-spacing: 0.06em;
  color: rgba(248, 244, 233, 0.78);
}

.page-about .about-hero__stats {
  position: relative;
  z-index: 1;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin: clamp(20px, 2.6vw, 30px) 0 0;
  padding: clamp(16px, 2vw, 22px) 0 0;
  border-top: 1px solid rgba(248, 244, 233, 0.18);
}

.page-about .about-hero__stats li {
  display: grid;
  gap: 4px;
}

.page-about .about-hero__stat-num {
  font-family: var(--font-mono);
  font-size: clamp(19px, 2.4vw, 26px);
  line-height: 1;
  color: var(--ivory);
}

.page-about .about-hero__stat-k {
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--celadon);
}

/* 页内索引 */
.page-about .about-toc {
  padding: 0 0 clamp(30px, 4.4vw, 60px);
}

.page-about .about-toc .index-label {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--patina);
}

.page-about .about-toc__list {
  list-style: none;
  display: flex;
  gap: 10px;
  margin: 14px 0 0;
  padding: 0 0 6px;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-toc__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-toc__list li {
  flex: 0 0 auto;
}

.page-about .about-toc__list a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  border-radius: var(--radius-pill);
  background: var(--mist);
  color: var(--ink);
  font-size: 13px;
  letter-spacing: 0.06em;
  text-decoration: none;
  white-space: nowrap;
  transition: background 0.25s var(--ease), color 0.25s var(--ease), transform 0.25s var(--ease);
}

.page-about .about-toc__list a:hover,
.page-about .about-toc__list a:focus-visible {
  background: var(--ink);
  color: var(--ivory);
  transform: translateY(-2px);
}

.page-about .about-toc__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--cinnabar);
}

.page-about .about-toc__list a:hover .about-toc__num,
.page-about .about-toc__list a:focus-visible .about-toc__num {
  color: var(--gold);
}

/* 起点与定位 */
.page-about .about-start__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  align-items: start;
}

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

.page-about .about-start__figure img,
.page-about .about-team__figure img,
.page-about .about-timeline__figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--about-radius);
  object-fit: cover;
  background: var(--mist);
}

.page-about .media__caption {
  margin-top: 10px;
  font-size: 12px;
  line-height: 1.7;
  letter-spacing: 0.06em;
  color: var(--patina);
}

.page-about .prose {
  margin-top: clamp(16px, 2.2vw, 24px);
  max-width: 62ch;
}

.page-about .prose p {
  margin: 0 0 1.1em;
  font-size: clamp(15px, 1.3vw, 16.5px);
  line-height: 1.85;
  color: rgba(28, 27, 24, 0.84);
}

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

/* 版本演进 */
.page-about .about-timeline__head {
  display: grid;
  gap: 18px;
  margin-bottom: clamp(20px, 3vw, 36px);
}

.page-about .about-timeline__head .btn {
  justify-self: start;
}

.page-about .about-timeline__lede {
  max-width: 52ch;
}

.page-about .about-timeline__figure {
  margin: 0 0 clamp(22px, 3.2vw, 40px);
}

.page-about .about-timeline__list {
  list-style: none;
  display: grid;
  gap: clamp(12px, 1.8vw, 20px);
  margin: 0;
  padding: 0;
}

.page-about .about-timeline__item {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(12px, 1.6vw, 22px);
  padding: clamp(18px, 2.4vw, 30px);
  border-radius: var(--about-radius);
  background: var(--mist);
  transition: background 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.page-about .about-timeline__item:hover {
  background: #ded4c0;
  box-shadow: var(--shadow-card);
}

.page-about .about-timeline__stamp {
  display: flex;
  align-items: center;
  gap: 12px;
}

.page-about .about-timeline__year {
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.4vw, 36px);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .about-timeline__badge {
  padding: 3px 11px;
  border-radius: var(--radius-pill);
  background: var(--gold);
  color: var(--graphite);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
}

.page-about .about-timeline__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(19px, 2.2vw, 24px);
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: 0.02em;
  color: var(--graphite);
}

.page-about .about-timeline__summary {
  margin: 8px 0 0;
  max-width: 54ch;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(28, 27, 24, 0.76);
}

/* 展开组 */
.page-about .disclosure {
  margin-top: 4px;
}

.page-about .disclosure__btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
  padding: 8px 16px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-pill);
  background: transparent;
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 12px;
  letter-spacing: 0.1em;
  cursor: pointer;
  transition: background 0.25s var(--ease), color 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-about .disclosure__btn:hover {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--ivory);
}

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

.page-about .disclosure__icon {
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1;
  transition: transform 0.3s var(--ease);
}

.page-about [data-disclosure][data-open] .disclosure__icon {
  transform: rotate(45deg);
}

.page-about .disclosure__panel {
  overflow: hidden;
}

.js .page-about .disclosure__panel {
  max-height: 0;
  opacity: 0;
  transition: max-height 0.45s var(--ease), opacity 0.3s var(--ease);
}

.js .page-about [data-disclosure][data-open] .disclosure__panel {
  max-height: 760px;
  opacity: 1;
}

.page-about .disclosure__body {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px dashed rgba(28, 27, 24, 0.18);
  font-size: 14.5px;
  line-height: 1.82;
  color: rgba(28, 27, 24, 0.82);
}

.page-about .disclosure__body p {
  margin: 0 0 0.9em;
}

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

/* 团队 */
.page-about .about-team__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  align-items: start;
}

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

.page-about .about-team__lede {
  max-width: 50ch;
}

.page-about .about-team__roles {
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: clamp(20px, 2.8vw, 32px) 0 0;
  padding: 1px;
  border-radius: var(--radius-lg);
  background: rgba(28, 27, 24, 0.12);
  overflow: hidden;
}

.page-about .about-team__roles li {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding: clamp(15px, 2vw, 22px);
  background: var(--ivory);
}

.page-about .about-team__role-num {
  flex: 0 0 auto;
  min-width: 34px;
  font-family: var(--font-mono);
  font-size: 27px;
  line-height: 1;
  color: var(--cinnabar);
}

.page-about .about-team__roles h3 {
  margin: 0 0 5px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--graphite);
}

.page-about .about-team__roles p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(28, 27, 24, 0.74);
}

/* 数据口径 */
.page-about .about-principle__slab {
  padding: clamp(26px, 4vw, 58px);
  border-radius: var(--about-radius);
  background: linear-gradient(160deg, var(--ink) 0%, #062b25 100%);
  color: var(--ivory);
}

.page-about .about-principle__title {
  color: var(--ivory);
}

.page-about .about-principle__lede {
  margin: 16px 0 0;
  max-width: 58ch;
  font-size: clamp(14.5px, 1.3vw, 16.5px);
  line-height: 1.85;
  color: rgba(248, 244, 233, 0.8);
}

.page-about .about-principle__scroll {
  margin-top: clamp(22px, 3vw, 34px);
  border-radius: var(--radius-md);
}

.page-about .about-principle__caption {
  caption-side: top;
  padding-bottom: 12px;
  text-align: left;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--celadon);
}

.page-about .about-principle__table {
  width: 100%;
  min-width: 640px;
  border-collapse: collapse;
  font-size: 14px;
}

.page-about .about-principle__table th,
.page-about .about-principle__table td {
  padding: 14px 16px;
  text-align: left;
  vertical-align: top;
  line-height: 1.7;
  border-bottom: 1px solid rgba(248, 244, 233, 0.16);
}

.page-about .about-principle__table th {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.14em;
  white-space: nowrap;
  color: var(--gold);
}

.page-about .about-principle__table td {
  color: rgba(248, 244, 233, 0.86);
}

.page-about .about-principle__table td:first-child {
  font-weight: 600;
  white-space: nowrap;
  color: var(--celadon);
}

.page-about .about-principle__table tbody tr:last-child th,
.page-about .about-principle__table tbody tr:last-child td {
  border-bottom: none;
}

.page-about .about-principle__table tbody tr:hover {
  background: rgba(248, 244, 233, 0.06);
}

.page-about .about-principle__risk {
  margin: clamp(18px, 2.4vw, 28px) 0 0;
  padding: 15px 18px;
  border-left: 3px solid var(--cinnabar);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  background: rgba(184, 50, 42, 0.16);
  font-size: 13px;
  line-height: 1.8;
  color: rgba(248, 244, 233, 0.9);
}

.page-about .about-principle__risk a {
  color: var(--gold);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* 合作生态 */
.page-about .about-eco__head {
  display: grid;
  gap: 16px;
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-about .about-eco__head .btn {
  justify-self: start;
}

.page-about .about-eco__lede {
  max-width: 50ch;
}

.page-about .about-eco__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(13px, 1.8vw, 20px);
}

.page-about .about-eco__card {
  display: grid;
  gap: 10px;
  align-content: start;
  padding: clamp(20px, 2.6vw, 30px);
  border-radius: var(--radius-lg);
}

.page-about .about-eco__num {
  font-family: var(--font-mono);
  font-size: clamp(34px, 4vw, 46px);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--wine);
}

.page-about .about-eco__card h3 {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--graphite);
}

.page-about .about-eco__card p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.78;
  color: rgba(28, 27, 24, 0.74);
}

.page-about .about-eco__milestones {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  border-top: 1px solid var(--about-line);
}

.page-about .about-eco__milestones li {
  display: grid;
  gap: 6px;
  padding: 15px 0;
  border-bottom: 1px solid var(--about-line);
  font-size: 14px;
  line-height: 1.75;
  color: rgba(28, 27, 24, 0.8);
}

.page-about .about-eco__year {
  font-family: var(--font-mono);
  font-size: 16px;
  letter-spacing: 0.04em;
  color: var(--cinnabar);
}

.page-about .about-eco__note {
  background: rgba(169, 200, 184, 0.28);
  border-left-color: var(--ink);
}

/* 服务边界 */
.page-about .about-boundary__slab {
  padding: clamp(26px, 4vw, 56px);
  border-radius: var(--about-radius);
  background: linear-gradient(150deg, var(--wine) 0%, #4b131c 100%);
  color: var(--ivory);
}

.page-about .about-boundary__title {
  color: var(--ivory);
}

.page-about .about-boundary__lede {
  margin: 16px 0 0;
  max-width: 60ch;
  font-size: clamp(14.5px, 1.3vw, 16px);
  line-height: 1.85;
  color: rgba(248, 244, 233, 0.84);
}

.page-about .about-boundary__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(12px, 1.8vw, 20px);
  margin-top: clamp(20px, 3vw, 32px);
}

.page-about .about-boundary__item {
  padding: 16px 18px;
  border: 1px solid rgba(248, 244, 233, 0.18);
  border-radius: var(--radius-md);
  background: rgba(248, 244, 233, 0.08);
}

.page-about .about-boundary__k {
  margin: 0 0 6px;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-about .about-boundary__v {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: rgba(248, 244, 233, 0.92);
}

.page-about .about-boundary__v--mono,
.page-about .about-boundary__v--mail {
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: 0.01em;
  word-break: break-word;
}

.page-about .about-boundary__note {
  margin: clamp(20px, 2.6vw, 28px) 0 0;
  max-width: 68ch;
  font-size: 13px;
  line-height: 1.82;
  color: rgba(248, 244, 233, 0.78);
}

.page-about .about-boundary__note a {
  color: var(--gold);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* 进入视口动效 */
.page-about [data-reveal] {
  opacity: 1;
  transform: none;
}

.js .page-about [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
}

.js .page-about [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* 平板与桌面 */
@media (min-width: 700px) {
  .page-about .about-team__roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

  .page-about .about-boundary__item--wide {
    grid-column: 1 / -1;
  }

  .page-about .about-eco__milestones li {
    grid-template-columns: 104px minmax(0, 1fr);
    align-items: baseline;
    gap: 4px 18px;
  }

  .page-about .about-eco__milestones .num {
    justify-self: start;
  }
}

@media (min-width: 940px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .about-start__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }

  .page-about .section__head {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: end;
    gap: 24px;
  }

  .page-about .about-timeline__head,
  .page-about .about-eco__head {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: end;
  }

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

  .page-about .about-timeline__item {
    grid-template-columns: 148px minmax(0, 1fr);
    padding-left: clamp(22px, 2.6vw, 36px);
    border-left: 2px solid rgba(201, 162, 39, 0.42);
    border-radius: 0 var(--about-radius) var(--about-radius) 0;
  }

  .page-about .about-timeline__item::before {
    content: "";
    position: absolute;
    left: -7px;
    top: clamp(28px, 3vw, 40px);
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--gold);
    box-shadow: 0 0 0 4px var(--ivory);
  }

  .page-about .about-timeline__stamp {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }
}

@media (min-width: 1180px) {
  .page-about .about-hero__panel {
    padding: 42px 40px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about [data-reveal],
  .js .page-about [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .js .page-about .disclosure__panel {
    transition: none;
  }
}