.page-about {
  --about-num-size: clamp(44px, 8vw, 92px);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  padding-bottom: clamp(48px, 7vw, 96px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-top: clamp(20px, 3vw, 36px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(90deg, rgba(7, 28, 22, .055) 0 1px, transparent 1px 24px);
  -webkit-mask-image: linear-gradient(180deg, #000 0%, transparent 72%);
  mask-image: linear-gradient(180deg, #000 0%, transparent 72%);
  pointer-events: none;
}

.page-about .about-hero .breadcrumb {
  position: relative;
  margin-bottom: clamp(20px, 3vw, 36px);
}

.page-about .about-hero__grid {
  position: relative;
  display: grid;
  gap: clamp(28px, 4vw, 52px);
  padding-bottom: clamp(32px, 5vw, 64px);
}

.page-about .about-hero__index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--teal);
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-serif);
  font-weight: 200;
  font-size: clamp(32px, 6.2vw, 70px);
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .about-hero__intro {
  margin: clamp(18px, 2.4vw, 26px) 0 0;
  max-width: 46ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.9;
  color: var(--ink);
}

.page-about .about-hero__lead .btn {
  margin-top: clamp(22px, 2.8vw, 30px);
}

.page-about .about-hero__facts {
  margin: 0;
  border-top: 1px solid var(--line-ink-strong);
}

.page-about .fact {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line-ink);
}

.page-about .fact dt {
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--slate);
}

.page-about .fact dd {
  margin: 0;
  text-align: right;
  font-size: 13px;
  color: var(--slate);
}

.page-about .fact__num {
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.4vw, 26px);
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -.02em;
  margin-right: 2px;
}

.page-about .about-hero__figure {
  position: relative;
  margin: 0;
  border-radius: var(--r-lg);
  overflow: hidden;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.page-about .about-hero__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: clamp(28px, 4vw, 44px) clamp(16px, 3vw, 32px) clamp(14px, 2vw, 22px);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--paper);
  background: linear-gradient(transparent, rgba(7, 28, 22, .78));
}

/* ---------- 目录 + 章节骨架 ---------- */
.page-about .about-layout {
  display: grid;
  gap: clamp(20px, 4vw, 40px);
  padding-top: clamp(48px, 7vw, 96px);
}

.page-about .about-toc__title {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--slate);
}

.page-about .about-toc__list {
  list-style: none;
  margin: 0;
  padding: 0 0 4px;
  display: flex;
  gap: 6px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-toc__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 14px;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  white-space: nowrap;
  font-size: 13px;
  color: var(--slate);
  text-decoration: none;
  transition: color var(--dur) ease, background-color var(--dur) ease, border-color var(--dur) ease;
}

.page-about .about-toc__link:hover {
  color: var(--ink);
  background: var(--paper-2);
}

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

.page-about .about-toc__num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--teal);
}

.page-about .about-toc__link.is-active,
.page-about .about-toc__link[aria-current="true"] {
  color: var(--ink);
  background: var(--paper-2);
  border-color: var(--line-ink);
}

.page-about .about-toc__link.is-active .about-toc__num,
.page-about .about-toc__link[aria-current="true"] .about-toc__num {
  color: var(--ink);
}

.page-about .chapter {
  padding-top: clamp(32px, 5vw, 60px);
  margin-top: clamp(40px, 6vw, 80px);
  border-top: 1px solid var(--line-ink);
}

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

.page-about .chapter__num {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 300;
  font-size: var(--about-num-size);
  line-height: .9;
  letter-spacing: -.05em;
  color: var(--teal);
  opacity: .5;
}

.page-about .chapter__title {
  margin: 10px 0 0;
  font-family: var(--font-serif);
  font-weight: 200;
  font-size: clamp(24px, 4vw, 40px);
  line-height: 1.28;
  letter-spacing: -.005em;
}

.page-about .chapter__body {
  margin-top: clamp(16px, 2.4vw, 24px);
  max-width: 62ch;
}

.page-about .chapter__body p {
  margin: 0 0 1.1em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.9;
}

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

.page-about .chapter__figure {
  margin: clamp(24px, 3.4vw, 36px) 0 0;
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--paper-2);
}

.page-about .chapter__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.page-about .chapter__caption {
  padding: 12px clamp(14px, 2vw, 20px) 14px;
  font-size: 12px;
  line-height: 1.7;
  color: var(--slate);
  background: var(--paper-2);
}

/* ---------- 时间线 ---------- */
.page-about .rhythm {
  margin-top: clamp(24px, 3.4vw, 36px);
  background: var(--ink);
  color: var(--paper);
  border-radius: var(--r-lg);
  padding: clamp(22px, 4vw, 46px);
  background-image: repeating-linear-gradient(0deg, rgba(43, 231, 200, .07) 0 1px, transparent 1px 46px);
}

.page-about .rhythm__head {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: clamp(16px, 2.4vw, 26px);
}

.page-about .rhythm__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .rhythm__hint {
  margin: 0;
  font-size: 12px;
  color: rgba(244, 238, 223, .55);
}

.page-about .rhythm__list {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 24px;
}

.page-about .rhythm__list::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 14px;
  bottom: 14px;
  width: 1px;
  background: var(--line-paper);
}

.page-about .tl {
  position: relative;
  display: grid;
  gap: 4px;
  padding: 16px 0;
  border-top: 1px solid var(--line-paper);
  transition: border-color var(--dur) ease;
}

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

.page-about .tl::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 22px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--cyan);
  transition: background-color var(--dur) ease, box-shadow var(--dur) ease;
}

.page-about .tl:hover::before,
.page-about .tl:focus-within::before {
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(43, 231, 200, .16);
}

.page-about .tl__time {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--cyan);
}

.page-about .tl__title {
  margin: 0;
  font-family: var(--font-body);
  font-size: clamp(15px, 1.7vw, 17px);
  font-weight: 500;
  line-height: 1.5;
  color: var(--white);
}

.page-about .tl__note {
  margin: 4px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: rgba(244, 238, 223, .7);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  list-style: none;
  margin: clamp(22px, 3vw, 34px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-ink);
  border: 1px solid var(--line-ink);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .team-grid__item {
  background: var(--paper);
  padding: clamp(16px, 2.4vw, 26px) clamp(14px, 2vw, 22px);
}

.page-about .team-grid__num {
  display: block;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(32px, 5vw, 50px);
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--ink);
}

.page-about .team-grid__label {
  display: block;
  margin-top: 8px;
  font-size: 12px;
  letter-spacing: .05em;
  color: var(--slate);
}

.page-about .network {
  list-style: none;
  margin: clamp(18px, 2.6vw, 28px) 0 0;
  padding: 0;
}

.page-about .network__item {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px dashed var(--line-ink);
}

.page-about .network__num {
  flex: 0 0 auto;
  min-width: 46px;
  font-family: var(--font-mono);
  font-size: clamp(18px, 2.2vw, 22px);
  font-weight: 600;
  letter-spacing: -.02em;
  color: var(--teal);
}

.page-about .network__text {
  font-size: clamp(14px, 1.5vw, 15px);
  line-height: 1.8;
  color: var(--ink);
}

/* ---------- 四级校验 ---------- */
.page-about .checks-wrap {
  display: grid;
  gap: clamp(24px, 4vw, 38px);
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .checks {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .checks__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: 14px;
  row-gap: 4px;
  padding: 16px 0;
  border-top: 1px solid var(--line-ink);
}

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

.page-about .checks__num {
  grid-row: 1 / span 2;
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border-radius: var(--r-pill);
  background: var(--ink-2);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .04em;
}

.page-about .checks__title {
  margin: 0;
  font-family: var(--font-body);
  font-size: clamp(15px, 1.7vw, 17px);
  font-weight: 500;
  line-height: 1.5;
  color: var(--ink);
}

.page-about .checks__text {
  margin: 0;
  font-size: clamp(14px, 1.5vw, 15px);
  line-height: 1.85;
  color: var(--slate);
}

.page-about .chapter__figure--side {
  margin-top: 0;
}

/* ---------- 专题与认可 ---------- */
.page-about .annual {
  display: grid;
  gap: clamp(18px, 3vw, 30px);
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .annual__panel {
  background: var(--ink-2);
  color: var(--paper);
  border-radius: var(--r-lg);
  padding: clamp(22px, 3.4vw, 38px);
  display: grid;
  align-content: start;
  gap: 6px;
}

.page-about .annual__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .annual__big {
  margin: 6px 0 0;
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-size: 14px;
  color: rgba(244, 238, 223, .72);
}

.page-about .annual__num {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(56px, 9vw, 104px);
  line-height: .9;
  letter-spacing: -.04em;
  color: var(--orange);
}

.page-about .annual__name {
  margin: 6px 0 0;
  font-family: var(--font-serif);
  font-weight: 300;
  font-size: clamp(18px, 2.2vw, 24px);
  color: var(--white);
}

.page-about .annual__text {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(244, 238, 223, .72);
}

.page-about .annual__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .annual__item {
  padding: 16px 0;
  border-bottom: 1px solid var(--line-ink);
}

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

.page-about .annual__item-title {
  margin: 0;
  font-family: var(--font-body);
  font-size: clamp(15px, 1.7vw, 17px);
  font-weight: 500;
  line-height: 1.55;
  color: var(--ink);
}

.page-about .annual__item-text {
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--slate);
}

/* ---------- 线下见面 ---------- */
.page-about .meet {
  margin-top: clamp(22px, 3vw, 32px);
  padding: clamp(22px, 4vw, 44px);
  border-radius: var(--r-lg);
  background: var(--paper-2);
  background-image: radial-gradient(rgba(7, 28, 22, .1) 1px, transparent 1px);
  background-size: 18px 18px;
}

.page-about .meet__text {
  margin: 0 0 14px;
  max-width: 62ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.9;
  color: var(--ink);
}

.page-about .meet__links {
  display: grid;
  gap: 12px;
  margin-top: clamp(18px, 2.6vw, 26px);
}

.page-about .meet__link {
  display: grid;
  gap: 4px;
  padding: 16px 18px;
  background: var(--white);
  border: 1px solid var(--line-ink);
  border-radius: var(--r-md);
  text-decoration: none;
  color: var(--ink);
  transition: border-color var(--dur) ease, transform var(--dur) ease, background-color var(--dur) ease;
}

.page-about .meet__link:hover {
  border-color: var(--teal);
  transform: translateY(-2px);
}

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

.page-about .meet__link-title {
  font-size: 15px;
  font-weight: 500;
  line-height: 1.5;
}

.page-about .meet__link-desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate);
}

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

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

  .page-about .annual {
    grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
    align-items: start;
  }
}

@media (min-width: 860px) {
  .page-about .checks-wrap {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    align-items: start;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .65fr);
    align-items: end;
  }

  .page-about .tl {
    grid-template-columns: 132px minmax(0, 1fr);
    align-items: baseline;
    column-gap: 20px;
  }

  .page-about .tl__time {
    grid-column: 1;
    grid-row: 1;
  }

  .page-about .tl__title {
    grid-column: 2;
    grid-row: 1;
  }

  .page-about .tl__note {
    grid-column: 2;
    grid-row: 2;
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    margin-top: 0;
    transition: max-height .24s ease, opacity .24s ease, margin-top .24s ease;
  }

  .page-about .tl:hover .tl__note,
  .page-about .tl:focus-within .tl__note {
    max-height: 8em;
    opacity: 1;
    margin-top: 6px;
  }
}

@media (min-width: 960px) {
  .page-about .about-layout {
    grid-template-columns: 196px minmax(0, 1fr);
    column-gap: clamp(36px, 5vw, 88px);
  }

  .page-about .about-toc {
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-about .about-toc__list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-toc__link {
    display: flex;
    width: 100%;
    justify-content: flex-start;
    padding: 9px 12px;
    border-radius: var(--r-sm);
    white-space: normal;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .meet__link,
  .page-about .tl,
  .page-about .tl::before,
  .page-about .about-toc__link {
    transition: none;
  }

  .page-about .meet__link:hover {
    transform: none;
  }

  .page-about .tl__note {
    max-height: none;
    opacity: 1;
    transition: none;
  }
}