.page-about {
  position: relative;
  overflow-x: hidden;
  background:
    radial-gradient(920px 540px at 88% -8%, rgba(37, 230, 200, .15), transparent 62%),
    radial-gradient(720px 440px at -10% 24%, rgba(255, 107, 74, .10), transparent 60%),
    var(--bo-night);
  color: var(--bo-ice);
  font-family: var(--bo-font-body);
}

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

.page-about .about-shell {
  width: var(--bo-shell);
  margin: 0 auto;
  padding: clamp(26px, 5vw, 56px) var(--bo-gutter) clamp(70px, 10vw, 130px);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 0 0 clamp(22px, 4vw, 40px);
  padding: 0;
  list-style: none;
  font-family: var(--bo-font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--bo-slate);
}

.page-about .about-crumb__list li {
  display: flex;
  align-items: center;
  gap: 10px;
}

.page-about .about-crumb__list li + li::before {
  content: "/";
  color: var(--bo-line-soft);
}

.page-about .about-crumb__list a {
  color: var(--bo-slate);
  text-decoration: none;
  transition: color 200ms ease;
}

.page-about .about-crumb__list a:hover,
.page-about .about-crumb__list a:focus-visible {
  color: var(--bo-cyan);
}

/* ---------- 首屏 ---------- */
.page-about .about-masthead__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 5vw, 52px);
  align-items: end;
}

.page-about .about-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 clamp(14px, 2.4vw, 22px);
  padding: 6px 14px 6px 8px;
  border: 1px solid var(--bo-line);
  border-radius: 999px;
  font-family: var(--bo-font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--bo-glow);
}

.page-about .about-eyebrow span {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--bo-cyan);
  color: var(--bo-ink);
  font-weight: 700;
}

.page-about .about-h1 {
  margin: 0 0 clamp(18px, 3vw, 26px);
  font-family: var(--bo-font-display);
  font-weight: 200;
  font-size: clamp(2.1rem, 7.4vw, 4.5rem);
  line-height: 1.06;
  letter-spacing: -.02em;
  color: var(--bo-ice);
}

.page-about .about-h1__sub {
  display: block;
  margin-top: .18em;
  font-weight: 800;
  font-size: .52em;
  line-height: 1.28;
  letter-spacing: -.01em;
  color: var(--bo-cyan);
}

.page-about .about-lede {
  max-width: 46ch;
  margin: 0 0 clamp(22px, 3vw, 32px);
  font-family: var(--bo-font-round);
  font-size: clamp(1rem, 1.6vw, 1.1rem);
  line-height: 1.92;
  color: rgba(234, 242, 255, .82);
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 24px;
  border-radius: 999px;
  font-family: var(--bo-font-display);
  font-weight: 700;
  font-size: .92rem;
  text-decoration: none;
  transition: transform 200ms ease, box-shadow 200ms ease, border-color 200ms ease, color 200ms ease;
}

.page-about .about-btn--solid {
  background: var(--bo-cyan);
  color: var(--bo-ink);
  box-shadow: 4px 4px 0 rgba(4, 7, 13, .85);
}

.page-about .about-btn--solid:hover,
.page-about .about-btn--solid:focus-visible {
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 rgba(4, 7, 13, .85);
}

.page-about .about-btn--line {
  border: 1px solid var(--bo-line);
  color: var(--bo-ice);
}

.page-about .about-btn--line:hover,
.page-about .about-btn--line:focus-visible {
  border-color: var(--bo-cyan);
  color: var(--bo-cyan);
}

.page-about .about-masthead__figure {
  position: relative;
  margin: 0;
  padding: 10px;
  border: 1px solid var(--bo-line);
  border-radius: var(--bo-radius-lg);
  background: linear-gradient(155deg, rgba(14, 59, 65, .55), rgba(10, 22, 40, .7));
  box-shadow: var(--bo-shadow-float);
}

.page-about .about-masthead__figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: calc(var(--bo-radius-lg) - 8px);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 24px), calc(100% - 24px) 100%, 0 100%);
}

.page-about .about-masthead__figure figcaption {
  margin-top: 12px;
  font-family: var(--bo-font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--bo-slate);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 16px;
  margin-top: clamp(46px, 7vw, 86px);
  padding: 16px 0;
  border-top: 1px solid var(--bo-line);
  border-bottom: 1px solid var(--bo-line-soft);
}

.page-about .about-index__label {
  font-family: var(--bo-font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--bo-coral);
}

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

.page-about .about-index__list a {
  display: inline-block;
  padding: 6px 13px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-family: var(--bo-font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--bo-slate);
  text-decoration: none;
  transition: color 200ms ease, border-color 200ms ease, background 200ms ease;
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  color: var(--bo-cyan);
  border-color: var(--bo-line);
  background: rgba(37, 230, 200, .08);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  margin-top: var(--bo-stack);
  scroll-margin-top: 130px;
}

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 6px 18px;
  align-items: baseline;
  margin-bottom: clamp(24px, 4vw, 44px);
  padding-bottom: 18px;
  border-bottom: 1px solid var(--bo-line-soft);
}

.page-about .about-chapter__no {
  grid-row: 1 / span 2;
  align-self: start;
  padding-bottom: 3px;
  border-bottom: 2px solid var(--bo-cyan);
  font-family: var(--bo-font-mono);
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--bo-cyan);
}

.page-about .about-chapter__title {
  grid-column: 2;
  margin: 0;
  font-family: var(--bo-font-display);
  font-weight: 300;
  font-size: clamp(1.55rem, 4vw, 2.5rem);
  line-height: 1.2;
  letter-spacing: -.02em;
  color: var(--bo-ice);
}

.page-about .about-chapter__kicker {
  grid-column: 2;
  margin: 0;
  font-family: var(--bo-font-round);
  font-size: .95rem;
  line-height: 1.75;
  color: var(--bo-slate);
}

/* ---------- 通用文本与分栏 ---------- */
.page-about .about-text {
  max-width: 62ch;
  margin: 0 0 1.05em;
  font-size: clamp(1rem, 1.3vw, 1.06rem);
  line-height: 1.92;
  color: rgba(234, 242, 255, .86);
}

.page-about .about-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 44px);
  align-items: start;
}

.page-about .about-points {
  display: grid;
  gap: 14px;
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-points li {
  padding: 16px 20px;
  border-left: 2px solid var(--bo-cyan);
  border-radius: 0 var(--bo-radius) var(--bo-radius) 0;
  background: var(--bo-surface);
}

.page-about .about-points strong {
  display: block;
  margin-bottom: 6px;
  font-family: var(--bo-font-display);
  font-weight: 700;
  font-size: 1rem;
  color: var(--bo-ice);
}

.page-about .about-points p {
  margin: 0;
  font-family: var(--bo-font-round);
  font-size: .93rem;
  line-height: 1.78;
  color: rgba(234, 242, 255, .72);
}

/* ---------- 速览面板 ---------- */
.page-about .about-facts {
  padding: clamp(20px, 3vw, 30px);
  border: 1px solid var(--bo-line);
  border-radius: var(--bo-radius-lg);
  background: linear-gradient(155deg, rgba(14, 59, 65, .78), rgba(10, 22, 40, .92));
  box-shadow: var(--bo-shadow-hard);
}

.page-about .about-facts__title {
  margin: 0 0 18px;
  font-family: var(--bo-font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--bo-cyan);
}

.page-about .about-facts dl {
  display: grid;
  gap: 16px;
  margin: 0;
}

.page-about .about-facts__row {
  padding-bottom: 14px;
  border-bottom: 1px dashed rgba(126, 143, 166, .28);
}

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

.page-about .about-facts dt {
  font-family: var(--bo-font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--bo-slate);
}

.page-about .about-facts dd {
  margin: 6px 0 0;
  font-family: var(--bo-font-display);
  font-size: 1.02rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--bo-ice);
}

/* ---------- 图与说明 ---------- */
.page-about .about-figure {
  margin: 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--bo-line-soft);
  border-radius: var(--bo-radius);
}

.page-about .about-figure--wide {
  margin-bottom: clamp(24px, 4vw, 38px);
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-family: var(--bo-font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--bo-slate);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(232px, 1fr));
  gap: 16px;
  padding: 4px 2px 16px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  scrollbar-color: var(--bo-cyan) transparent;
}

.page-about .about-timeline__item {
  position: relative;
  padding: 26px 18px 20px;
  border: 1px solid var(--bo-line-soft);
  border-radius: var(--bo-radius);
  background: rgba(14, 59, 65, .52);
  scroll-snap-align: start;
  transition: transform 220ms ease, border-color 220ms ease, background 220ms ease;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 18px;
  right: 18px;
  height: 3px;
  background: var(--bo-cyan);
  transform: scaleX(.26);
  transform-origin: left center;
  transition: transform 300ms ease;
}

.page-about .about-timeline__item:hover,
.page-about .about-timeline__item:focus-visible {
  transform: translateY(-4px);
  border-color: var(--bo-line);
  background: rgba(14, 59, 65, .82);
  outline: none;
}

.page-about .about-timeline__item:hover::before,
.page-about .about-timeline__item:focus-visible::before {
  transform: scaleX(1);
}

.page-about .about-timeline__meta {
  margin: 0 0 10px;
  font-family: var(--bo-font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--bo-coral);
}

.page-about .about-timeline__name {
  margin: 0 0 10px;
  font-family: var(--bo-font-display);
  font-weight: 700;
  font-size: 1.04rem;
  line-height: 1.4;
  color: var(--bo-ice);
}

.page-about .about-timeline__brief {
  margin: 0;
  font-family: var(--bo-font-round);
  font-size: .9rem;
  line-height: 1.78;
  color: rgba(234, 242, 255, .66);
  transition: color 220ms ease;
}

.page-about .about-timeline__item:hover .about-timeline__brief,
.page-about .about-timeline__item:focus-visible .about-timeline__brief {
  color: var(--bo-glow);
}

/* ---------- 团队折叠卡 ---------- */
.page-about .about-team {
  display: grid;
  gap: 12px;
  margin-top: 6px;
}

.page-about .about-team__card {
  border: 1px solid var(--bo-line-soft);
  border-left: 3px solid var(--bo-cyan);
  border-radius: 0 var(--bo-radius) var(--bo-radius) 0;
  background: rgba(14, 59, 65, .42);
  transition: border-color 220ms ease, background 220ms ease;
}

.page-about .about-team__card[open] {
  border-left-color: var(--bo-coral);
  background: rgba(14, 59, 65, .7);
}

.page-about .about-team__card summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 16px 20px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-team__card summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--bo-font-mono);
  font-size: 1.1rem;
  line-height: 1;
  color: var(--bo-cyan);
}

.page-about .about-team__card[open] summary::after {
  content: "−";
  color: var(--bo-coral);
}

.page-about .about-team__role {
  font-family: var(--bo-font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--bo-cyan);
}

.page-about .about-team__duty {
  font-family: var(--bo-font-display);
  font-weight: 600;
  font-size: 1.02rem;
  color: var(--bo-ice);
}

.page-about .about-team__body {
  padding: 0 20px 18px;
}

.page-about .about-team__body ul {
  display: grid;
  gap: 8px;
  margin: 0;
  padding-left: 18px;
}

.page-about .about-team__body li {
  font-family: var(--bo-font-round);
  font-size: .92rem;
  line-height: 1.78;
  color: rgba(234, 242, 255, .74);
}

/* ---------- 文档体系 ---------- */
.page-about .about-docs {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 42px);
  align-items: start;
}

.page-about .about-code {
  display: inline-block;
  margin: 8px 0 0;
  padding: 12px 18px;
  border-radius: 12px;
  background: var(--bo-cyan);
  box-shadow: var(--bo-shadow-hard);
  font-family: var(--bo-font-mono);
  font-size: clamp(.9rem, 2.2vw, 1.16rem);
  letter-spacing: .1em;
  color: var(--bo-ink);
  word-break: break-word;
}

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

.page-about .about-docs__cats li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 8px 16px;
  padding: 18px 20px;
  border: 1px solid var(--bo-line-soft);
  border-radius: var(--bo-radius);
  background: rgba(10, 22, 40, .55);
  transition: border-color 220ms ease, transform 220ms ease;
}

.page-about .about-docs__cats li:hover {
  border-color: var(--bo-line);
  transform: translateY(-3px);
}

.page-about .about-docs__tag {
  grid-row: span 2;
  align-self: start;
  padding: 4px 12px;
  border: 1px solid var(--bo-line);
  border-radius: 999px;
  font-family: var(--bo-font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--bo-cyan);
}

.page-about .about-docs__cats strong {
  font-family: var(--bo-font-display);
  font-weight: 600;
  font-size: 1rem;
  color: var(--bo-ice);
}

.page-about .about-docs__cats p {
  grid-column: 2;
  margin: 0;
  font-family: var(--bo-font-round);
  font-size: .9rem;
  line-height: 1.78;
  color: rgba(234, 242, 255, .7);
}

/* ---------- 合作生态（暖沙色块） ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(20px, 3vw, 36px);
  padding: clamp(26px, 4vw, 48px);
  border-radius: var(--bo-radius-lg);
  background: var(--bo-sand);
  box-shadow: var(--bo-shadow-hard);
  color: #101a26;
}

.page-about .about-partners__lead {
  margin: 0 0 14px;
  font-family: var(--bo-font-round);
  font-size: 1.02rem;
  line-height: 1.88;
  color: rgba(16, 26, 38, .84);
}

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

.page-about .about-partners__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-partners__tags li {
  padding: 9px 16px;
  border: 1px solid rgba(16, 26, 38, .24);
  border-radius: 999px;
  background: rgba(16, 26, 38, .06);
  font-family: var(--bo-font-display);
  font-weight: 700;
  font-size: .9rem;
  color: #101a26;
}

/* ---------- 数据小卡 ---------- */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: var(--bo-stack);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 12px;
  min-height: 138px;
  padding: 20px 18px;
  border: 1px solid var(--bo-line);
  border-radius: var(--bo-radius);
  background: linear-gradient(170deg, rgba(14, 59, 65, .82), rgba(10, 22, 40, .92));
  box-shadow: var(--bo-shadow-hard);
}

.page-about .about-stat__num {
  font-family: var(--bo-font-display);
  font-weight: 200;
  font-size: clamp(1.9rem, 5.4vw, 2.8rem);
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--bo-cyan);
}

.page-about .about-stat:nth-child(even) .about-stat__num {
  color: var(--bo-coral);
}

.page-about .about-stat__num small {
  margin-left: 4px;
  font-size: .4em;
  font-weight: 600;
  letter-spacing: 0;
}

.page-about .about-stat__label {
  margin: 0;
  font-family: var(--bo-font-round);
  font-size: .88rem;
  line-height: 1.65;
  color: rgba(234, 242, 255, .72);
}

/* ---------- 结尾去向 ---------- */
.page-about .about-next {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3vw, 34px);
  margin-top: clamp(48px, 7vw, 84px);
  padding: clamp(26px, 4vw, 46px);
  border: 1px solid var(--bo-line);
  border-radius: var(--bo-radius-lg);
  background:
    radial-gradient(620px 320px at 100% 0%, rgba(37, 230, 200, .18), transparent 66%),
    rgba(14, 59, 65, .42);
}

.page-about .about-next h2 {
  margin: 0 0 12px;
  font-family: var(--bo-font-display);
  font-weight: 300;
  font-size: clamp(1.4rem, 3.2vw, 2rem);
  letter-spacing: -.02em;
  color: var(--bo-ice);
}

.page-about .about-next p {
  max-width: 52ch;
  margin: 0;
  font-family: var(--bo-font-round);
  font-size: .98rem;
  line-height: 1.88;
  color: rgba(234, 242, 255, .8);
}

.page-about .about-next__links {
  display: grid;
  gap: 10px;
  align-content: center;
}

.page-about .about-next__link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 15px 18px;
  border: 1px solid var(--bo-line-soft);
  border-radius: 12px;
  font-family: var(--bo-font-display);
  font-weight: 600;
  font-size: .95rem;
  color: var(--bo-ice);
  text-decoration: none;
  transition: border-color 220ms ease, transform 220ms ease, color 220ms ease;
}

.page-about .about-next__link::after {
  content: "→";
  font-family: var(--bo-font-mono);
  color: var(--bo-cyan);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-color: var(--bo-cyan);
  transform: translateX(4px);
  color: var(--bo-glow);
}

/* ---------- 进入视口的渐显 ---------- */
.bo-js .page-about [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 620ms ease, transform 620ms ease;
}

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

/* ---------- 响应式 ---------- */
@media (min-width: 760px) {
  .page-about .about-partners {
    grid-template-columns: 7fr 5fr;
    align-items: center;
  }

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

@media (min-width: 900px) {
  .page-about .about-masthead__grid {
    grid-template-columns: 7fr 5fr;
  }

  .page-about .about-split {
    grid-template-columns: 7fr 5fr;
  }

  .page-about .about-split--flip {
    grid-template-columns: 5fr 7fr;
  }

  .page-about .about-docs {
    grid-template-columns: 4fr 8fr;
  }

  .page-about .about-next {
    grid-template-columns: 7fr 5fr;
    align-items: center;
  }
}

@media (max-width: 899px) {
  .page-about .about-chapter__head {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .page-about .about-chapter__no {
    grid-row: auto;
    justify-self: start;
  }

  .page-about .about-chapter__title,
  .page-about .about-chapter__kicker {
    grid-column: 1;
  }

  .page-about .about-chapter {
    scroll-margin-top: 96px;
  }
}

@media (max-width: 560px) {
  .page-about .about-docs__cats li {
    grid-template-columns: 1fr;
  }

  .page-about .about-docs__tag {
    grid-row: auto;
    justify-self: start;
  }

  .page-about .about-docs__cats p {
    grid-column: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: .01ms !important;
  }

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