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

.page-about img {
  display: block;
  max-width: 100%;
  height: auto;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-head);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(115% 85% at 92% 4%, rgba(23, 224, 214, .20), transparent 58%),
    radial-gradient(90% 70% at 4% 100%, rgba(242, 184, 75, .10), transparent 60%),
    var(--deep);
  color: var(--white);
  padding: clamp(1.25rem, 3vw, 2rem) 0 clamp(2.75rem, 6vw, 4.5rem);
}

.page-about .about-hero__crumbs {
  margin: 0 0 clamp(1.5rem, 4vw, 2.5rem);
}

.page-about .about-hero__crumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .45rem;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: .8rem;
  letter-spacing: .04em;
}

.page-about .about-hero__crumbs li + li::before {
  content: "/";
  margin-right: .45rem;
  color: rgba(255, 255, 255, .35);
}

.page-about .about-hero__crumbs a {
  color: var(--mist);
  text-decoration: none;
}

.page-about .about-hero__crumbs a:hover,
.page-about .about-hero__crumbs a:focus-visible {
  color: var(--white);
}

.page-about .about-hero__crumbs [aria-current="page"] {
  color: var(--white);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(2rem, 5vw, 3.5rem);
  align-items: start;
}

.page-about .about-hero .eyebrow {
  color: var(--cyan);
  margin: 0 0 .9rem;
}

.page-about .about-hero__title {
  margin: 0;
  font-size: clamp(2.1rem, 7.2vw, 4.2rem);
  line-height: 1.02;
  letter-spacing: -.025em;
  font-weight: 800;
}

.page-about .about-hero__hl {
  color: var(--cyan);
}

.page-about .about-hero__lede {
  margin: clamp(1.1rem, 3vw, 1.6rem) 0 0;
  max-width: 46ch;
  font-size: clamp(.95rem, 2.2vw, 1.08rem);
  line-height: 1.8;
  color: rgba(255, 255, 255, .82);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .65rem;
  margin-top: clamp(1.4rem, 3.5vw, 2rem);
}

.page-about .about-hero__card {
  background: var(--paper);
  color: var(--ink);
  border: 1px solid rgba(11, 42, 69, .08);
  border-radius: var(--r-lg);
  padding: clamp(1.15rem, 3vw, 1.6rem);
  box-shadow: var(--shadow-2);
}

.page-about .about-card__tag {
  display: flex;
  align-items: center;
  gap: .5rem;
  margin: 0;
  font-size: .8rem;
  letter-spacing: .1em;
  color: var(--deep);
  font-weight: 600;
}

.page-about .about-card__dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(242, 184, 75, .18);
}

.page-about .about-card__date {
  margin: .55rem 0 1rem;
  font-size: .95rem;
  color: var(--deep-soft);
  letter-spacing: .02em;
}

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

.page-about .about-card__list li {
  display: grid;
  gap: .15rem;
  padding: .6rem 0;
  border-top: 1px dashed rgba(11, 42, 69, .16);
}

.page-about .about-card__list span {
  font-size: .76rem;
  letter-spacing: .06em;
  color: var(--slate);
}

.page-about .about-card__list strong {
  font-size: .92rem;
  font-weight: 600;
  color: var(--ink);
  line-height: 1.45;
}

.page-about .about-card__link {
  display: inline-block;
  margin-top: .9rem;
  font-size: .85rem;
  color: var(--deep);
  text-decoration: none;
  border-bottom: 1px solid var(--cyan-deep);
  padding-bottom: 2px;
}

.page-about .about-card__link:hover,
.page-about .about-card__link:focus-visible {
  color: var(--cyan-deep);
}

/* ---------- 概览带 ---------- */
.page-about .about-stats {
  background: var(--paper-2);
  border-top: 1px solid rgba(11, 42, 69, .08);
  border-bottom: 1px solid rgba(11, 42, 69, .08);
}

.page-about .about-stats__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.4rem 1rem;
  padding: clamp(1.6rem, 4vw, 2.6rem) 0;
}

.page-about .about-stats__num {
  margin: 0 0 .3rem;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 4.2vw, 2.2rem);
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--deep);
}

.page-about .about-stats__label {
  margin: 0;
  font-size: .8rem;
  line-height: 1.55;
  color: var(--slate);
}

/* ---------- 双栏布局 ---------- */
.page-about .about-layout {
  display: grid;
  gap: clamp(1.5rem, 4vw, 2.5rem);
  padding-block: clamp(2rem, 5vw, 3.75rem);
}

.page-about .about-index__label {
  margin: 0 0 .55rem;
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .2em;
  color: var(--slate);
}

.page-about .about-index__list {
  display: flex;
  gap: .5rem;
  margin: 0;
  padding: 0 0 .3rem;
  list-style: none;
  overflow-x: auto;
}

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

.page-about .about-index__list a {
  display: inline-flex;
  align-items: baseline;
  gap: .4rem;
  white-space: nowrap;
  padding: .4rem .75rem;
  border: 1px solid rgba(11, 42, 69, .16);
  border-radius: var(--r-pill);
  font-size: .8rem;
  color: var(--ink-soft);
  text-decoration: none;
  transition: color .18s var(--ease), border-color .18s var(--ease), background-color .18s var(--ease);
}

.page-about .about-index__list a .mono {
  font-size: .72rem;
  color: var(--slate);
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  color: var(--deep);
  border-color: var(--cyan);
}

.page-about .about-index__list a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.page-about .about-index__list a.is-current,
.page-about .about-index__list a[aria-current] {
  color: var(--deep);
  border-color: var(--cyan-deep);
  background: rgba(23, 224, 214, .14);
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding-block: clamp(1.6rem, 4vw, 2.5rem);
  border-top: 1px solid rgba(11, 42, 69, .12);
}

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

.page-about .about-chapter__head {
  display: flex;
  align-items: baseline;
  gap: .7rem;
  margin: 0 0 .9rem;
}

.page-about .about-chapter__num {
  font-family: var(--font-mono);
  font-size: clamp(1.4rem, 4vw, 2.1rem);
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--warm);
}

.page-about .about-chapter h2 {
  margin: 0;
  font-size: clamp(1.3rem, 3.3vw, 1.85rem);
  line-height: 1.28;
  letter-spacing: -.01em;
  color: var(--deep);
}

.page-about .about-chapter .prose p {
  margin: 0 0 .95rem;
}

.page-about .about-chapter .prose a {
  color: var(--deep);
  text-decoration: none;
  border-bottom: 1px solid var(--cyan-deep);
}

.page-about .about-chapter .prose a:hover,
.page-about .about-chapter .prose a:focus-visible {
  color: var(--cyan-deep);
}

/* ---------- 旁注 ---------- */
.page-about .about-note {
  margin: 1.1rem 0 0;
  padding: .9rem 1.1rem;
  background: var(--paper-2);
  border-left: 3px solid var(--amber);
  border-radius: var(--r-sm);
  font-size: .87rem;
  line-height: 1.7;
  color: var(--ink-soft);
}

.page-about .about-note strong {
  color: var(--deep);
}

.page-about .about-note--reveal {
  cursor: default;
  transition: border-color .2s var(--ease), background-color .2s var(--ease);
}

.page-about .about-note--reveal > p {
  margin: .4rem 0 0;
}

.page-about .about-note--reveal:hover,
.page-about .about-note--reveal:focus {
  border-left-color: var(--cyan-deep);
  background: rgba(191, 233, 230, .42);
}

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

.page-about .about-note__more {
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height .24s var(--ease), opacity .24s var(--ease);
}

.page-about .about-note__more p {
  margin: .55rem 0 0;
}

.page-about .about-note--reveal:hover .about-note__more,
.page-about .about-note--reveal:focus .about-note__more,
.page-about .about-note--reveal:focus-within .about-note__more {
  max-height: 12rem;
  opacity: 1;
}

/* ---------- 横向时间轴 ---------- */
.page-about .about-timeline {
  margin: 1.4rem 0 0;
  padding: clamp(1rem, 3vw, 1.6rem);
  border-radius: var(--r-lg);
  background:
    radial-gradient(120% 130% at 15% 0%, rgba(23, 224, 214, .18), transparent 55%),
    var(--deep);
  color: var(--white);
}

.page-about .about-timeline__figure {
  margin: 0 0 1.1rem;
  border-radius: var(--r-md);
  overflow: hidden;
  background: rgba(255, 255, 255, .06);
}

.page-about .about-timeline__figure img {
  width: 100%;
  object-fit: cover;
}

.page-about .about-timeline__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
}

.page-about .about-timeline__item {
  position: relative;
  padding: 1rem 0 1rem 1.35rem;
  border-left: 1px solid rgba(255, 255, 255, .18);
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -4.5px;
  top: 1.35rem;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan);
}

.page-about .about-timeline__item.is-update::before {
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(242, 184, 75, .16);
}

.page-about .about-timeline__item:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 4px;
  border-radius: var(--r-sm);
}

.page-about .about-timeline__year {
  margin: 0 0 .3rem;
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .14em;
  color: var(--cyan);
}

.page-about .about-timeline__item.is-update .about-timeline__year {
  color: var(--amber);
}

.page-about .about-timeline__title {
  margin: 0 0 .3rem;
  font-size: .98rem;
  line-height: 1.35;
  color: var(--white);
}

.page-about .about-timeline__desc {
  margin: 0;
  font-size: .83rem;
  line-height: 1.6;
  color: rgba(255, 255, 255, .72);
}

.page-about .about-timeline__more {
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  margin: 0;
  font-size: .8rem;
  line-height: 1.65;
  color: var(--mist);
  transition: max-height .22s var(--ease), opacity .22s var(--ease), margin-top .22s var(--ease);
}

.page-about .about-timeline__item:hover .about-timeline__more,
.page-about .about-timeline__item:focus .about-timeline__more,
.page-about .about-timeline__item:focus-within .about-timeline__more {
  max-height: 9rem;
  opacity: 1;
  margin-top: .5rem;
}

/* ---------- 图文分栏 ---------- */
.page-about .about-split {
  display: grid;
  gap: clamp(1.2rem, 3vw, 2rem);
}

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

.page-about .about-figure img {
  width: 100%;
  border-radius: var(--r-md);
  box-shadow: var(--shadow-1);
}

.page-about .about-figure figcaption {
  margin-top: .55rem;
  font-size: .78rem;
  line-height: 1.55;
  color: var(--slate);
}

.page-about .about-roles {
  display: grid;
  gap: .7rem;
  margin: 1.2rem 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-roles li {
  padding: .8rem .95rem;
  background: var(--paper-2);
  border-top: 2px solid var(--mist);
  border-radius: 0 0 var(--r-md) var(--r-md);
}

.page-about .about-roles strong {
  display: block;
  margin-bottom: .2rem;
  font-size: .92rem;
  color: var(--deep);
}

.page-about .about-roles span {
  font-size: .83rem;
  line-height: 1.6;
  color: var(--ink-soft);
}

.page-about .about-data {
  display: grid;
  gap: .55rem;
  margin: 1.2rem 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-data li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: .7rem;
  align-items: baseline;
  padding: .6rem .85rem;
  background: rgba(191, 233, 230, .34);
  border-radius: var(--r-sm);
  font-size: .85rem;
  line-height: 1.6;
  color: var(--ink-soft);
}

.page-about .about-data__k {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  color: var(--deep);
  background: var(--white);
  border-radius: var(--r-sm);
  padding: .12rem .4rem;
}

/* ---------- 价值列表 ---------- */
.page-about .about-reasons {
  list-style: none;
  margin: 1.2rem 0 0;
  padding: 0;
}

.page-about .about-reason {
  display: grid;
  gap: .3rem;
  padding: 1rem 0;
  border-top: 1px solid rgba(11, 42, 69, .12);
}

.page-about .about-reason:first-child {
  border-top: 2px solid var(--deep);
}

.page-about .about-reason h3 {
  margin: 0;
  font-size: 1.02rem;
  line-height: 1.4;
  color: var(--deep);
}

.page-about .about-reason p {
  margin: 0;
  font-size: .88rem;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta__grid {
  display: grid;
  gap: 1.5rem;
  align-items: center;
}

.page-about .about-cta .eyebrow {
  color: var(--cyan);
  margin: 0 0 .4rem;
}

.page-about .about-cta h2 {
  margin: .2rem 0 .7rem;
  font-size: clamp(1.45rem, 3.6vw, 2.05rem);
  line-height: 1.3;
  letter-spacing: -.01em;
  color: var(--white);
}

.page-about .about-cta p {
  margin: 0;
  max-width: 52ch;
  font-size: .92rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, .78);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .65rem;
}

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

@media (min-width: 760px) {
  .page-about .about-stats__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1.5rem clamp(1rem, 3vw, 2rem);
  }

  .page-about .about-reason {
    grid-template-columns: 11rem minmax(0, 1fr);
    gap: 1.25rem;
    align-items: baseline;
  }
}

@media (min-width: 840px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, .8fr);
    align-items: start;
  }

  .page-about .about-split--reverse {
    grid-template-columns: minmax(0, .85fr) minmax(0, 1fr);
  }

  .page-about .about-timeline__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0 clamp(.75rem, 2vw, 1.4rem);
  }

  .page-about .about-timeline__item {
    border-left: 0;
    border-top: 1px solid rgba(255, 255, 255, .18);
    padding: 1.3rem .4rem 0 0;
  }

  .page-about .about-timeline__item::before {
    left: 0;
    top: -4.5px;
  }

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    gap: clamp(2rem, 4vw, 3.5rem);
  }

  .page-about .about-hero__card {
    justify-self: end;
    width: 100%;
  }
}

@media (min-width: 980px) {
  .page-about .about-layout {
    grid-template-columns: 180px minmax(0, 1fr);
    gap: clamp(2rem, 4vw, 3.5rem);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 108px;
  }

  .page-about .about-index__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
    border-left: 1px solid rgba(11, 42, 69, .14);
  }

  .page-about .about-index__list li {
    flex: 1 1 auto;
  }

  .page-about .about-index__list a {
    display: flex;
    border: 0;
    border-left: 2px solid transparent;
    border-radius: 0;
    margin-left: -1px;
    padding: .5rem 0 .5rem .9rem;
    white-space: normal;
    background: transparent;
    line-height: 1.45;
  }

  .page-about .about-index__list a.is-current,
  .page-about .about-index__list a[aria-current] {
    border-left-color: var(--cyan-deep);
    background: transparent;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__list a,
  .page-about .about-note--reveal,
  .page-about .about-timeline__more,
  .page-about .about-note__more {
    transition: none;
  }
}