.page-about {
  --about-line: rgba(245, 241, 232, .12);
  color: var(--text);
}

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

.page-about .about-flow > section {
  scroll-margin-top: 6rem;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding-block: clamp(1.25rem, 3vw, 2rem) clamp(2.25rem, 5vw, 3.5rem);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -12% -6% 26%;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(48% 60% at 12% 6%, rgba(139, 92, 246, .20), transparent 68%),
    radial-gradient(44% 54% at 88% 18%, rgba(224, 164, 88, .16), transparent 70%),
    radial-gradient(40% 46% at 58% 82%, rgba(111, 162, 135, .13), transparent 72%);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(1.5rem, 4vw, 2.5rem);
  margin-top: clamp(1.25rem, 3vw, 2rem);
}

.page-about .about-hero__lede {
  min-width: 0;
}

.page-about .about-hero h1 {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(1.95rem, 5.6vw, 3.25rem);
  line-height: 1.2;
  letter-spacing: -.01em;
  color: var(--cream);
  margin: .6rem 0 1.1rem;
  max-width: 22ch;
}

.page-about .about-hero__lead {
  margin: 0 0 .85rem;
  font-size: clamp(1rem, 1.6vw, 1.125rem);
  line-height: 1.85;
  color: var(--text);
  max-width: 52ch;
}

.page-about .about-hero__sub {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--text-dim);
  border-left: 2px solid rgba(224, 164, 88, .5);
  padding-left: .9rem;
  max-width: 46ch;
}

.page-about .about-hero__fig {
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--edge-strong);
  box-shadow: 0 34px 70px -40px rgba(0, 0, 0, .95);
}

.page-about .about-hero__fig img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-facts {
  list-style: none;
  margin: clamp(2rem, 5vw, 3.25rem) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-facts li {
  background: rgba(11, 26, 42, .82);
  padding: 1rem 1.15rem;
  display: flex;
  flex-direction: column;
  gap: .3rem;
}

.page-about .about-facts__num {
  font-size: clamp(1.15rem, 2.4vw, 1.5rem);
  color: var(--amber);
  letter-spacing: .02em;
}

.page-about .about-facts__key {
  font-size: .8125rem;
  color: var(--text-dim);
  letter-spacing: .06em;
}

/* ---------- 主体两列 ---------- */

.page-about .about-body {
  display: flex;
  flex-direction: column;
  gap: clamp(1.75rem, 4vw, 2.5rem);
  padding-bottom: clamp(3rem, 7vw, 5rem);
}

.page-about .about-flow {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: clamp(2.75rem, 6vw, 4.5rem);
}

/* ---------- 索引 ---------- */

.page-about .about-index {
  order: -1;
  border: 1px solid var(--edge);
  border-radius: var(--radius-sm);
  background: rgba(31, 41, 51, .5);
  padding: .85rem 1rem;
  overflow-x: auto;
}

.page-about .about-index__title {
  margin: 0 0 .6rem;
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .18em;
  color: var(--stone);
}

.page-about .about-index ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: .5rem;
}

.page-about .about-index a {
  display: block;
  white-space: nowrap;
  font-size: .875rem;
  color: var(--text);
  text-decoration: none;
  padding: .35rem .7rem;
  border-radius: 999px;
  border: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease), background-color .2s var(--ease);
}

.page-about .about-index a:hover,
.page-about .about-index a:focus-visible {
  color: var(--amber);
  border-color: rgba(224, 164, 88, .45);
  background: rgba(224, 164, 88, .09);
}

/* ---------- 起点与初心 ---------- */

.page-about .origin-card {
  background: linear-gradient(160deg, rgba(31, 41, 51, .9), rgba(11, 26, 42, .9));
  border: 1px solid var(--edge);
  border-radius: var(--radius);
  padding: clamp(1.15rem, 3vw, 1.6rem);
  transition: transform .3s var(--ease), border-color .3s var(--ease);
}

.page-about .origin-card:hover {
  transform: translateY(-3px);
  border-color: rgba(224, 164, 88, .4);
}

.page-about .origin-card .card__title {
  margin: .6rem 0 .5rem;
}

/* ---------- 时间轴 ---------- */

.page-about .journey-band {
  position: relative;
  padding-left: clamp(.9rem, 2.5vw, 1.5rem);
  border-left: 1px solid var(--about-line);
}

.page-about .tl {
  --tl-gap: 2rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .tl-node {
  position: relative;
  display: grid;
  gap: .85rem;
  padding-bottom: clamp(1.75rem, 4vw, 2.5rem);
}

.page-about .tl-mark {
  display: flex;
  align-items: baseline;
  gap: .75rem;
}

.page-about .tl-num {
  font-size: 1.4rem;
  color: var(--amber);
  letter-spacing: .04em;
}

.page-about .tl-phase {
  font-size: .8125rem;
  letter-spacing: .22em;
  color: var(--text-dim);
}

.page-about .tl-card {
  background: linear-gradient(160deg, rgba(31, 41, 51, .92), rgba(11, 26, 42, .92));
  border: 1px solid var(--edge);
  border-radius: var(--radius);
  padding: clamp(1.1rem, 3vw, 1.6rem);
  transition: transform .3s var(--ease), border-color .3s var(--ease), box-shadow .3s var(--ease);
}

.page-about .tl-card:hover,
.page-about .tl-card:focus-within {
  transform: translateY(-3px);
  border-color: rgba(224, 164, 88, .45);
  box-shadow: 0 24px 44px -30px rgba(0, 0, 0, .95);
}

.page-about .tl-card__title {
  margin: 0 0 .5rem;
  font-family: var(--font-serif);
  font-size: clamp(1.1rem, 2.4vw, 1.35rem);
  color: var(--cream);
}

.page-about .tl-card p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--text);
}

.page-about .tl-more {
  margin-top: 1rem;
  border-top: 1px dashed var(--edge);
  padding-top: .75rem;
}

.page-about .tl-more summary {
  cursor: pointer;
  list-style: none;
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  min-height: 2rem;
  font-family: var(--font-mono);
  font-size: .8125rem;
  letter-spacing: .1em;
  color: var(--amber);
}

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

.page-about .tl-more summary::after {
  content: "＋";
  font-size: .9rem;
}

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

.page-about .tl-more p {
  margin-top: .55rem;
  color: var(--text-dim);
}

/* ---------- 版本演进（浅色区） ---------- */

.page-about .about-invert {
  --text: rgba(11, 26, 42, .76);
  --text-dim: rgba(11, 26, 42, .56);
  --edge: rgba(11, 26, 42, .14);
  --edge-strong: rgba(11, 26, 42, .28);
  --stone: rgba(11, 26, 42, .5);
  background: var(--cream);
  color: var(--ink);
  border-radius: var(--radius);
  padding: clamp(1.75rem, 5vw, 3.25rem);
}

.page-about .about-invert .section-title {
  color: var(--ink);
}

.page-about .about-invert .section-lead {
  color: rgba(11, 26, 42, .7);
}

.page-about .about-invert .eyebrow {
  color: var(--clay);
}

.page-about .vg-figure {
  margin: 0 0 clamp(1.5rem, 4vw, 2.25rem);
  border-radius: var(--radius-sm);
  overflow: hidden;
  border: 1px solid var(--edge);
  background: rgba(255, 255, 255, .6);
}

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

.page-about .vg-figure figcaption {
  font-size: .8125rem;
  color: var(--text-dim);
  padding: .7rem .95rem;
  border-top: 1px solid var(--edge);
}

.page-about .vg-grid {
  display: grid;
  gap: 1rem;
}

.page-about .vg-card {
  background: rgba(255, 255, 255, .74);
  border: 1px solid var(--edge);
  border-radius: var(--radius-sm);
  padding: clamp(1rem, 2.5vw, 1.4rem);
  box-shadow: 0 20px 40px -34px rgba(11, 26, 42, .55);
}

.page-about .vg-card__kicker {
  margin: 0;
  font-size: .75rem;
  letter-spacing: .16em;
  color: var(--clay);
}

.page-about .vg-card__title {
  margin: .45rem 0 .55rem;
  font-family: var(--font-serif);
  font-size: clamp(1.05rem, 2.2vw, 1.25rem);
  color: var(--ink);
}

.page-about .vg-card p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: rgba(11, 26, 42, .72);
}

/* ---------- 用户陪伴 ---------- */

.page-about .companion-grid {
  display: grid;
  gap: clamp(1.5rem, 4vw, 2.5rem);
}

.page-about .companion-fig {
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--edge-strong);
  box-shadow: 0 34px 70px -44px rgba(0, 0, 0, .95);
}

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

.page-about .companion-list {
  display: grid;
  gap: .2rem;
}

.page-about .comp-item {
  display: grid;
  grid-template-columns: 2.4rem minmax(0, 1fr);
  gap: .9rem;
  padding: 1.05rem 0;
  border-top: 1px solid var(--about-line);
}

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

.page-about .comp-item__num {
  font-size: 1rem;
  color: var(--celadon);
  letter-spacing: .04em;
  padding-top: .2rem;
}

.page-about .comp-item__body {
  min-width: 0;
}

.page-about .comp-item__body h3 {
  margin: 0 0 .35rem;
  font-family: var(--font-serif);
  font-size: clamp(1.05rem, 2.2vw, 1.2rem);
  color: var(--cream);
}

.page-about .comp-item__body p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--text);
}

.page-about .companion-cta {
  margin: clamp(1.5rem, 4vw, 2rem) 0 0;
}

/* ---------- 往后方向 ---------- */

.page-about .ahead-card {
  background: linear-gradient(150deg, rgba(74, 93, 78, .38), rgba(31, 41, 51, .72));
  border: 1px solid var(--edge);
  border-radius: var(--radius);
  padding: clamp(1.15rem, 3vw, 1.6rem);
  transition: transform .3s var(--ease), border-color .3s var(--ease);
}

.page-about .ahead-card:hover {
  transform: translateY(-3px);
  border-color: rgba(111, 162, 135, .5);
}

.page-about .ahead-card__title {
  margin: .8rem 0 .55rem;
  font-family: var(--font-serif);
  font-size: clamp(1.05rem, 2.3vw, 1.25rem);
  color: var(--cream);
}

.page-about .ahead-card p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--text);
}

/* ---------- 结尾引导 ---------- */

.page-about .about-cta {
  background: linear-gradient(115deg, rgba(224, 164, 88, .16), rgba(139, 92, 246, .15) 55%, rgba(111, 162, 135, .15));
  border-top: 1px solid rgba(224, 164, 88, .35);
  border-bottom: 1px solid var(--edge);
}

.page-about .about-cta__inner {
  display: grid;
  gap: 1.5rem;
  padding-block: clamp(2.25rem, 6vw, 4rem);
}

.page-about .about-cta h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.4rem, 3.2vw, 2rem);
  line-height: 1.3;
  color: var(--cream);
  margin: .45rem 0 .6rem;
}

.page-about .about-cta__text {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--text-dim);
  max-width: 46ch;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
}

/* ---------- 断点 ---------- */

@media (min-width: 760px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 880px) {
  .page-about .tl {
    --tl-gap: clamp(2rem, 4vw, 3rem);
  }

  .page-about .tl-node {
    grid-template-columns: 8.5rem minmax(0, 1fr);
    column-gap: var(--tl-gap);
    padding-bottom: clamp(2rem, 4vw, 3rem);
  }

  .page-about .tl-node::after {
    content: "";
    position: absolute;
    left: calc(8.5rem + var(--tl-gap) / 2);
    top: 2.4rem;
    bottom: .4rem;
    width: 1px;
    background: linear-gradient(to bottom, rgba(224, 164, 88, .45), var(--about-line));
  }

  .page-about .tl-node:last-child::after {
    display: none;
  }

  .page-about .tl-mark {
    flex-direction: column;
    align-items: flex-end;
    gap: .2rem;
    padding-right: .35rem;
  }

  .page-about .tl-phase {
    letter-spacing: .14em;
  }

  .page-about .vg-grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 1.25rem;
  }

  .page-about .vg-card:nth-child(1) {
    grid-column: 1 / span 6;
  }

  .page-about .vg-card:nth-child(2) {
    grid-column: 8 / span 5;
    margin-top: 2.5rem;
  }

  .page-about .vg-card:nth-child(3) {
    grid-column: 2 / span 5;
  }

  .page-about .vg-card:nth-child(4) {
    grid-column: 8 / span 5;
    margin-top: 2.5rem;
  }

  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    column-gap: 3rem;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    align-items: end;
    column-gap: clamp(1.5rem, 3vw, 2.5rem);
  }

  .page-about .about-hero__lede {
    grid-column: 1 / span 6;
  }

  .page-about .about-hero__fig {
    grid-column: 8 / -1;
    margin-bottom: -1.5rem;
  }

  .page-about .companion-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    align-items: start;
  }
}

@media (min-width: 1060px) {
  .page-about .about-body {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 13rem;
    column-gap: clamp(2rem, 4vw, 3.5rem);
    align-items: start;
  }

  .page-about .about-index {
    order: 0;
    position: sticky;
    top: 6rem;
    overflow: visible;
    background: transparent;
    border: 0;
    border-left: 1px solid var(--edge-strong);
    border-radius: 0;
    padding: .25rem 0 .25rem 1.1rem;
  }

  .page-about .about-index ol {
    display: block;
  }

  .page-about .about-index li + li {
    margin-top: .15rem;
  }

  .page-about .about-index a {
    border-radius: var(--radius-sm);
    padding: .4rem .55rem;
  }
}