.page-about {
  --about-aside: 168px;
  --about-gap: clamp(1.4rem, 3.4vw, 3rem);
  position: relative;
}

/* ---------- 面包屑 ---------- */
.page-about .about-topbar {
  padding-top: clamp(1.2rem, 3vw, 2rem);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(1.6rem, 4vw, 3rem) clamp(2.2rem, 5vw, 3.6rem);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -30% -12% auto -32%;
  height: 560px;
  pointer-events: none;
  background:
    radial-gradient(58% 96% at 14% 34%, rgba(255, 107, 26, .17), transparent 70%),
    radial-gradient(48% 92% at 76% 8%, rgba(0, 229, 199, .14), transparent 72%),
    repeating-linear-gradient(90deg, rgba(124, 141, 181, .08) 0 1px, transparent 1px 96px),
    repeating-linear-gradient(0deg, rgba(124, 141, 181, .08) 0 1px, transparent 1px 96px);
}

.page-about .about-hero__shell {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.6rem, 4vw, 3rem);
}

.page-about .about-hero h1 {
  margin: 0 0 1.1rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.3rem, 6.6vw, 4.3rem);
  line-height: 1.02;
  letter-spacing: -.012em;
  color: var(--paper);
}

.page-about .about-hero .lede {
  max-width: 62ch;
  color: var(--body);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
  margin-top: 1.5rem;
}

/* 首屏章节索引 */
.page-about .about-hero__index {
  border-left: 2px solid var(--line-strong);
  padding-left: 1.1rem;
}

.page-about .about-hero__indexlabel {
  margin: 0 0 .75rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-hero__index ol {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: hx;
  display: grid;
  gap: .5rem;
}

.page-about .about-hero__index li {
  counter-increment: hx;
}

.page-about .about-hero__index a {
  display: flex;
  align-items: baseline;
  gap: .6rem;
  font-size: .9rem;
  line-height: 1.4;
  color: var(--soft);
  text-decoration: none;
  transition: color var(--t-fast);
}

.page-about .about-hero__index a::before {
  content: counter(hx, decimal-leading-zero);
  flex: none;
  font-family: var(--font-mono);
  font-size: .76rem;
  color: var(--muted);
  transition: color var(--t-fast);
}

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

.page-about .about-hero__index a:hover::before,
.page-about .about-hero__index a:focus-visible::before {
  color: var(--orange);
}

/* 首屏数据带 */
.page-about .about-tally {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: clamp(1.8rem, 4.4vw, 2.8rem);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--line);
}

.page-about .about-tally__cell {
  padding: 1.1rem 1.2rem 1.25rem;
  background: linear-gradient(180deg, rgba(17, 27, 63, .94), rgba(10, 17, 40, .94));
}

.page-about .about-tally__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.7rem, 4.4vw, 2.4rem);
  line-height: 1;
  color: var(--orange);
  margin-bottom: .5rem;
}

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

.page-about .about-tally__label {
  display: block;
  font-size: .85rem;
  line-height: 1.55;
  color: var(--muted);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-story {
  padding-bottom: clamp(2rem, 5vw, 3.4rem);
}

.page-about .about-chapter {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--about-gap);
  padding-block: clamp(2.2rem, 5vw, 3.6rem);
  border-top: 1px solid var(--line);
}

.page-about .about-chapter--last {
  border-bottom: 1px solid var(--line);
}

.page-about .about-chapter__aside {
  display: flex;
  align-items: baseline;
  gap: .7rem;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-chapter__num {
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: 0;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-chapter__stamp {
  color: var(--muted);
}

.page-about .about-chapter__title {
  margin: 0 0 1rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.7rem, 3.8vw, 2.6rem);
  line-height: 1.08;
  color: var(--paper);
}

.page-about .about-chapter__body p {
  margin: 0 0 1rem;
  max-width: 68ch;
  font-size: 1rem;
  line-height: 1.78;
  color: var(--body);
}

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

/* ---------- 引语 ---------- */
.page-about .about-quote {
  position: relative;
  margin: 1.6rem 0;
  padding: 1.15rem 1.3rem 1.1rem 2.9rem;
  border-left: 3px solid var(--orange);
  border-radius: 0 var(--r-md) var(--r-md) 0;
  background: linear-gradient(100deg, var(--orange-soft), rgba(255, 107, 26, 0) 78%);
}

.page-about .about-quote::before {
  content: "\201C";
  position: absolute;
  left: .85rem;
  top: .55rem;
  font-family: var(--font-display);
  font-size: 3.2rem;
  line-height: 1;
  color: rgba(255, 107, 26, .5);
}

.page-about .about-quote__text {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.08rem, 2.4vw, 1.5rem);
  line-height: 1.36;
  color: var(--paper);
}

.page-about .about-quote figcaption {
  margin-top: .65rem;
  font-size: .78rem;
  letter-spacing: .06em;
  color: var(--muted);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 1.6rem 0;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--ink-900);
}

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

.page-about .about-figure figcaption {
  padding: .75rem 1rem;
  font-size: .8rem;
  line-height: 1.6;
  color: var(--muted);
  border-top: 1px solid var(--line);
  background: rgba(17, 27, 63, .7);
}

/* ---------- 数据条 ---------- */
.page-about .about-band {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin: 1.7rem 0 .3rem;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--line);
}

.page-about .about-band__cell {
  padding: 1.05rem 1.15rem 1.15rem;
  background: var(--ink-900);
}

.page-about .about-band__num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.6rem, 3.6vw, 2rem);
  line-height: 1;
  color: var(--orange);
  margin-bottom: .5rem;
}

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

.page-about .about-band__label {
  display: block;
  font-size: .84rem;
  line-height: 1.55;
  color: var(--muted);
}

/* ---------- 团队角色 ---------- */
.page-about .about-roles {
  display: grid;
  grid-template-columns: 1fr;
  gap: .85rem;
  margin-top: 1.5rem;
}

.page-about .about-role {
  padding: 1.1rem 1.15rem 1.2rem;
  border: 1px solid var(--line);
  border-top: 3px solid var(--ink-700);
  border-radius: var(--r-sm);
  background: linear-gradient(180deg, rgba(27, 42, 94, .5), rgba(17, 27, 63, .86));
}

.page-about .about-role:nth-child(1) { border-top-color: var(--orange); }
.page-about .about-role:nth-child(2) { border-top-color: var(--cyan); }
.page-about .about-role:nth-child(3) { border-top-color: var(--amber); }

.page-about .about-role__title {
  margin: .7rem 0 .45rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.2rem;
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-role__text {
  margin: 0;
  font-size: .9rem;
  line-height: 1.7;
  color: var(--body);
}

/* ---------- 时间轴与折叠组 ---------- */
.page-about .about-timeline {
  margin: 1.5rem 0 0;
  padding: 0 0 0 1.1rem;
  list-style: none;
  border-left: 1px solid var(--line-strong);
  display: grid;
  gap: .55rem;
}

.page-about .about-timeline__item {
  position: relative;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: calc(-1.1rem - 5px);
  top: 1.05rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink-950);
  border: 2px solid var(--cyan);
}

.page-about .about-fold {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: rgba(17, 27, 63, .72);
  overflow: hidden;
  transition: border-color var(--t-fast);
}

.page-about .about-fold[open] {
  border-color: var(--line-strong);
}

.page-about .about-fold__head {
  display: flex;
  align-items: baseline;
  gap: .6rem;
  padding: .85rem 2.4rem .85rem 1rem;
  position: relative;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  line-height: 1.35;
  color: var(--paper);
}

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

.page-about .about-fold__head::after {
  content: "+";
  position: absolute;
  right: 1rem;
  top: .8rem;
  font-family: var(--font-mono);
  font-size: 1.1rem;
  color: var(--orange);
}

.page-about .about-fold[open] .about-fold__head::after {
  content: "\2212";
}

.page-about .about-fold__meta {
  margin-left: auto;
  padding-right: 1.2rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 400;
  letter-spacing: .08em;
  color: var(--muted);
}

.page-about .about-fold__body {
  padding: .1rem 1rem 1rem;
  border-top: 1px solid var(--line);
}

.page-about .about-fold__body p {
  margin: .8rem 0 0;
  font-size: .92rem;
  line-height: 1.75;
  color: var(--body);
}

/* ---------- 延伸入口 ---------- */
.page-about .about-next {
  display: grid;
  grid-template-columns: 1fr;
  gap: .8rem;
  margin-top: 1.6rem;
}

.page-about .about-next__card {
  display: block;
  padding: 1.15rem 1.15rem 1.3rem;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: linear-gradient(180deg, rgba(27, 42, 94, .58), rgba(17, 27, 63, .88));
  text-decoration: none;
  color: inherit;
  transition: border-color var(--t-fast), transform var(--t-fast), box-shadow var(--t-fast);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: var(--orange);
  transform: translateY(-3px);
  box-shadow: 0 16px 32px rgba(0, 0, 0, .38);
}

.page-about .about-next__card h3 {
  margin: 0 0 .45rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  line-height: 1.2;
  color: var(--paper);
}

.page-about .about-next__card p {
  margin: 0 0 .9rem;
  font-size: .9rem;
  line-height: 1.7;
  color: var(--body);
}

.page-about .about-next__go {
  display: block;
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .06em;
  color: var(--cyan);
}

.page-about .about-next__back {
  margin: 1.4rem 0 0;
  font-size: .9rem;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-next__back a {
  color: var(--soft);
  text-decoration: underline;
  text-decoration-color: var(--line-strong);
  text-underline-offset: 3px;
}

.page-about .about-next__back a:hover,
.page-about .about-next__back a:focus-visible {
  color: var(--orange);
  text-decoration-color: currentColor;
}

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

@media (min-width: 720px) {
  .page-about .about-tally {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

@media (min-width: 780px) {
  .page-about .about-next {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr) 282px;
    align-items: start;
  }

  .page-about .about-hero__index {
    padding-left: 1.3rem;
  }

  .page-about .about-chapter {
    grid-template-columns: var(--about-aside) minmax(0, 1fr);
    gap: clamp(1.6rem, 4vw, 3.4rem);
  }

  .page-about .about-chapter__aside {
    position: sticky;
    top: 2rem;
    align-self: start;
    display: block;
    padding-top: .35rem;
  }

  .page-about .about-chapter__num {
    display: block;
    margin-bottom: .6rem;
    font-size: 1.7rem;
  }

  .page-about .about-chapter__stamp {
    display: block;
    line-height: 1.6;
  }

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

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

@media (min-width: 1100px) {
  .page-about {
    --about-aside: 190px;
  }

  .page-about .about-chapter__body p {
    font-size: 1.02rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-next__card,
  .page-about .about-hero__index a,
  .page-about .about-fold {
    transition: none;
  }

  .page-about .about-next__card:hover,
  .page-about .about-next__card:focus-visible {
    transform: none;
  }
}
</main>