.page-about {
  --about-rail-w: 240px;
  --about-split-gap: 56px;
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block-start: 22px;
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: 30px;
}

.page-about .about-hero .eyebrow {
  display: block;
  margin: 0 0 14px;
  color: var(--muted);
  font-size: 13px;
  letter-spacing: 0.1em;
}

.page-about .about-hero h1 {
  margin: 0;
  max-width: 18ch;
  font-size: clamp(30px, 7vw, 54px);
  line-height: 1.14;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: 17px;
  line-height: 1.78;
  color: var(--cyan-200);
}

.page-about .about-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  margin: 22px 0 0;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .about-hero__meta span {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.page-about .about-hero__meta span::before {
  content: "";
  flex: none;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--cyan-600);
}

.page-about .about-hero__figure {
  margin: 34px 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--ink-800);
}

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

/* ---------- 左右分屏 ---------- */
.page-about .about-split {
  display: grid;
  gap: 34px;
  padding-block: 52px 40px;
}

/* ---------- 左侧年份轴 ---------- */
.page-about .about-rail {
  min-width: 0;
}

.page-about .about-rail__title {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 10px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scrollbar-width: thin;
}

.page-about .about-rail__link {
  flex: none;
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--ink-700);
  border-radius: var(--pill);
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
  font-size: 14px;
  line-height: 1.4;
  transition: color 0.18s ease, background-color 0.18s ease, border-color 0.18s ease;
}

.page-about .about-rail__link .about-rail__year {
  flex: none;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--cyan-600);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--paper);
  border-color: var(--cyan-600);
}

.page-about .about-rail__link[aria-current="true"] {
  color: var(--ink-900);
  background: var(--gold);
  border-color: var(--gold);
  font-weight: 600;
}

.page-about .about-rail__link[aria-current="true"] .about-rail__year {
  color: var(--ink-900);
  opacity: 0.8;
}

/* ---------- 右侧长文 ---------- */
.page-about .about-body {
  min-width: 0;
}

.page-about .about-entry {
  padding-block: 30px;
  border-top: 1px solid var(--ink-700);
  scroll-margin-top: 110px;
}

.page-about .about-entry:first-child {
  border-top: 0;
  padding-block-start: 0;
}

.page-about .about-entry__year {
  margin: 0 0 10px;
  font-size: clamp(26px, 6vw, 38px);
  line-height: 1;
  letter-spacing: 0.03em;
  font-weight: 600;
  color: var(--cyan-600);
}

.page-about .about-entry__title {
  margin: 0 0 18px;
  font-size: clamp(20px, 3vw, 28px);
  line-height: 1.34;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-entry__body {
  display: grid;
  gap: 16px;
}

.page-about .about-entry__body > p {
  margin: 0;
  max-width: 34em;
  font-size: 16px;
  line-height: 1.78;
  color: var(--cyan-200);
}

.page-about .about-entry__body a {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid rgba(226, 163, 60, 0.45);
}

.page-about .about-entry__body a:hover,
.page-about .about-entry__body a:focus-visible {
  border-bottom-color: var(--gold);
}

/* ---------- 旁注 ---------- */
.page-about .about-note {
  margin: 0;
  padding: 14px 16px;
  border-radius: var(--radius-md);
  background: var(--ink-800);
  border-left: 3px solid var(--gold);
}

.page-about .about-note__label {
  margin: 0 0 6px;
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gold);
}

.page-about .about-note p:last-child {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--cyan-200);
}

.page-about .about-note a {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid rgba(226, 163, 60, 0.45);
}

/* ---------- 正文配图 ---------- */
.page-about .about-figure {
  margin: 10px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius-md);
  object-fit: cover;
  background: var(--ink-800);
}

.page-about .about-figure__caption {
  margin: 10px 0 0;
  max-width: 46em;
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 呼吸区 ---------- */
.page-about .about-breath {
  margin: 0 16px 68px;
  padding: 42px 26px;
  border-radius: var(--radius-lg);
  background: var(--paper);
}

.page-about .about-breath__inner {
  display: grid;
  gap: 16px;
}

.page-about .about-breath__num {
  margin: 0;
  font-size: clamp(38px, 9vw, 62px);
  line-height: 1;
  letter-spacing: 0.02em;
  font-weight: 600;
  color: var(--ink-900);
}

.page-about .about-breath__text {
  margin: 0;
  max-width: 44em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-800);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-next {
  padding-block: 0 72px;
}

.page-about .about-next__card {
  padding: 30px 22px;
  border-radius: var(--radius-lg);
  background: var(--ink-800);
  border: 1px solid var(--ink-700);
}

.page-about .about-next__card .eyebrow {
  display: block;
  margin: 0;
  color: var(--muted);
  font-size: 13px;
  letter-spacing: 0.1em;
}

.page-about .about-next__title {
  margin: 12px 0 0;
  font-size: clamp(22px, 3.6vw, 30px);
  line-height: 1.3;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--paper);
}

.page-about .about-next__lede {
  margin: 14px 0 0;
  max-width: 46em;
  font-size: 16px;
  line-height: 1.78;
  color: var(--cyan-200);
}

.page-about .about-next__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-block-start: 24px;
}

.page-about .about-next__more {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 22px 0 0;
  font-size: 14px;
  color: var(--muted);
}

.page-about .about-next__more a {
  color: var(--cyan-200);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid rgba(185, 214, 220, 0.35);
}

.page-about .about-next__more a:hover,
.page-about .about-next__more a:focus-visible {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 768px) {
  .page-about .about-hero {
    padding-block-start: 34px;
  }

  .page-about .about-hero__figure {
    margin-block-start: 42px;
    border-radius: var(--radius-lg);
  }

  .page-about .about-entry {
    padding-block: 38px;
  }

  .page-about .about-breath {
    margin-inline: 24px;
    padding: 52px 40px;
  }

  .page-about .about-next__card {
    padding: 44px 42px;
  }
}

@media (min-width: 1000px) {
  .page-about .about-split {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: var(--about-split-gap);
    padding-block: 64px 48px;
  }

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

  .page-about .about-rail__list {
    display: grid;
    gap: 2px;
    overflow: visible;
    padding: 0 0 0 24px;
    position: relative;
  }

  .page-about .about-rail__list::before {
    content: "";
    position: absolute;
    left: 7px;
    top: 12px;
    bottom: 12px;
    width: 1px;
    background: linear-gradient(180deg, var(--cyan-600), transparent);
  }

  .page-about .about-rail__link {
    display: flex;
    border: 0;
    border-radius: var(--radius-sm);
    padding: 7px 10px;
    white-space: normal;
    position: relative;
  }

  .page-about .about-rail__link::before {
    content: "";
    position: absolute;
    left: -21px;
    top: 50%;
    width: 8px;
    height: 8px;
    margin-top: -4px;
    border-radius: 50%;
    background: var(--ink-700);
    box-shadow: 0 0 0 3px var(--ink-900);
    transition: background-color 0.18s ease, transform 0.18s ease;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    color: var(--paper);
    background: var(--ink-800);
    border-color: transparent;
  }

  .page-about .about-rail__link[aria-current="true"] {
    color: var(--paper);
    background: var(--ink-800);
    border-color: transparent;
  }

  .page-about .about-rail__link[aria-current="true"] .about-rail__year {
    color: var(--cyan-200);
    opacity: 0.85;
  }

  .page-about .about-rail__link[aria-current="true"]::before {
    background: var(--gold);
    transform: scale(1.25);
  }
}

@media (min-width: 1080px) {
  .page-about .about-entry__body {
    grid-template-columns: minmax(0, 1fr) 208px;
    column-gap: 40px;
    align-items: start;
  }

  .page-about .about-entry__body > p,
  .page-about .about-entry__body > figure {
    grid-column: 1;
  }

  .page-about .about-entry__body > .about-note {
    grid-column: 2;
    grid-row: 1 / span 6;
  }
}

@media (min-width: 1320px) {
  .page-about .about-breath {
    max-width: var(--maxw);
    margin-inline: auto;
    padding: 58px 56px;
  }
}

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