.page-about {
  --about-rail: 176px;
  --about-figure-pad: 10px;
  display: block;
  background: var(--c-surface-alt);
  color: var(--c-text);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about .about-shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* ---------- 面包屑条 ---------- */
.page-about .about-crumb {
  background: var(--c-surface);
  border-bottom: 1px solid var(--c-line);
}

.page-about .about-crumb .about-shell {
  padding-block: 14px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  background: linear-gradient(160deg, var(--c-night) 0%, var(--c-navy) 88%);
  color: var(--c-on-dark);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(201, 209, 220, .07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 209, 220, .07) 1px, transparent 1px);
  background-size: 48px 48px;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--c-green) 0%, var(--c-amber) 46%, transparent 100%);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  padding-block: clamp(48px, 8vw, 100px);
}

.page-about .about-hero .eyebrow {
  color: var(--c-amber);
}

.page-about .about-hero__title {
  font-family: var(--font-head);
  font-size: clamp(1.85rem, 5.2vw, 3.4rem);
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: #FFFFFF;
  margin: 14px 0 0;
  max-width: 20ch;
}

.page-about .about-hero__lede {
  margin: 22px 0 0;
  max-width: 62ch;
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--c-on-dark-soft);
}

@media (min-width: 720px) {
  .page-about .about-hero__lede {
    font-size: var(--fs-20);
  }
}

.page-about .about-hero__marks {
  list-style: none;
  margin: 34px 0 0;
  padding: 24px 0 0;
  border-top: 1px solid var(--c-line-dark);
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 18px var(--gap);
}

.page-about .about-hero__marks li {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-hero__mark-num {
  font-family: var(--font-mono);
  font-size: var(--fs-28);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 0.02em;
  color: var(--c-amber);
}

.page-about .about-hero__mark-txt {
  font-size: var(--fs-14);
  line-height: 1.5;
  color: var(--c-on-dark-soft);
}

/* ---------- 主体双栏 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 52px);
  padding-block: var(--sec-y);
}

@media (min-width: 900px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(32px, 4vw, 64px);
  }
}

/* ---------- 左侧索引 ---------- */
.page-about .about-rail__title {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--c-text-mute);
  margin: 0 0 10px;
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 4px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 12px;
  border: 1px solid var(--c-line);
  background: var(--c-surface);
  color: var(--c-text-soft);
  text-decoration: none;
  white-space: nowrap;
  font-size: var(--fs-14);
  line-height: 1.4;
  transition: border-color var(--t-base) var(--ease), color var(--t-base) var(--ease), background var(--t-base) var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  border-color: var(--c-amber);
  color: var(--c-ink);
  background: rgba(242, 169, 59, .10);
}

.page-about .about-rail__num {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--c-amber-ink);
}

@media (min-width: 900px) {
  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 16px);
    align-self: start;
  }

  .page-about .about-rail__list {
    display: block;
    overflow: visible;
    padding: 0;
    border-left: 1px solid var(--c-line-strong);
  }

  .page-about .about-rail__list li + li {
    margin-top: 2px;
  }

  .page-about .about-rail__link {
    display: flex;
    width: 100%;
    border: 0;
    border-left: 2px solid transparent;
    background: transparent;
    padding: 9px 10px;
    white-space: normal;
    border-radius: 0;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    border-left-color: var(--c-amber);
    background: rgba(242, 169, 59, .09);
  }
}

/* ---------- 区块骨架 ---------- */
.page-about .about-block + .about-block {
  margin-top: clamp(42px, 6vw, 76px);
}

.page-about .about-block__head {
  border-top: 1px solid var(--c-line-strong);
  padding-top: 16px;
  margin-bottom: 22px;
}

.page-about .about-block__head h2 {
  margin: 8px 0 0;
  font-family: var(--font-head);
  font-size: clamp(1.45rem, 3.4vw, 2.15rem);
  font-weight: 700;
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--c-ink);
}

/* ---------- 正文 ---------- */
.page-about .about-prose p {
  margin: 0 0 1em;
  max-width: 68ch;
  font-size: var(--fs-16);
  line-height: 1.75;
  color: var(--c-text-soft);
}

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

.page-about .about-prose .mono {
  font-family: var(--font-mono);
  font-size: 0.95em;
  letter-spacing: 0.02em;
  color: var(--c-navy);
  background: rgba(11, 37, 69, .06);
  padding: 1px 5px;
}

.page-about .about-prose--lead p:first-of-type::first-letter {
  float: left;
  font-family: var(--font-head);
  font-size: 3.1em;
  line-height: 0.86;
  font-weight: 700;
  color: var(--c-navy);
  padding: 6px 10px 0 0;
}

/* ---------- 编者按卡 ---------- */
.page-about .about-note {
  margin-top: 22px;
  max-width: 62ch;
  padding: 18px 20px;
  background: var(--c-paper);
  border: 1px solid var(--c-line);
  border-left: 3px solid var(--c-amber);
  transition: transform var(--t-base) var(--ease), border-color var(--t-base) var(--ease), box-shadow var(--t-base) var(--ease);
}

.page-about .about-note:hover,
.page-about .about-note:focus-within {
  transform: translateY(-2px);
  border-color: var(--c-amber);
  box-shadow: var(--shadow-1);
}

.page-about .about-note__label {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--c-amber-ink);
}

.page-about .about-note p {
  margin: 0;
  font-size: var(--fs-16);
  line-height: 1.7;
  color: var(--c-ink);
}

.page-about .about-note .mono {
  font-family: var(--font-mono);
  font-size: 0.95em;
  color: var(--c-navy);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 24px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: var(--c-line-strong);
}

.page-about .about-timeline__item {
  position: relative;
  padding: 16px 0 18px;
  border-top: 1px solid var(--c-line);
}

.page-about .about-timeline__item:first-child {
  border-top: 0;
  padding-top: 4px;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 24px;
  width: 11px;
  height: 11px;
  background: var(--c-surface-alt);
  border: 2px solid var(--c-navy);
}

.page-about .about-timeline__item:first-child::before {
  top: 12px;
}

.page-about .about-timeline__item:hover::before {
  border-color: var(--c-amber);
  background: var(--c-amber);
}

.page-about .about-timeline__year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--fs-20);
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--c-navy);
}

.page-about .about-timeline__body h3 {
  margin: 8px 0 6px;
  font-family: var(--font-head);
  font-size: var(--fs-20);
  font-weight: 700;
  line-height: 1.35;
  color: var(--c-ink);
}

.page-about .about-timeline__body p {
  margin: 0;
  max-width: 66ch;
  font-size: var(--fs-16);
  line-height: 1.75;
  color: var(--c-text-soft);
}

@media (min-width: 900px) {
  .page-about .about-timeline__item {
    display: grid;
    grid-template-columns: 116px minmax(0, 1fr);
    gap: 0 20px;
    padding-block: 20px 22px;
  }

  .page-about .about-timeline__year {
    font-size: var(--fs-28);
  }

  .page-about .about-timeline__body h3 {
    margin-top: 0;
  }
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 28px 0 0;
  padding: var(--about-figure-pad);
  background: var(--c-surface);
  border: 1px solid var(--c-line);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  background: var(--c-mist);
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  line-height: 1.6;
  color: var(--c-text-mute);
}

@media (min-width: 900px) {
  .page-about .about-figure--narrow {
    max-width: 620px;
  }
}

/* ---------- 团队卡 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 24px;
}

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

.page-about .about-team__card {
  padding: 18px 18px 20px;
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-left: 3px solid var(--c-silver);
  transition: transform var(--t-base) var(--ease), border-color var(--t-base) var(--ease), box-shadow var(--t-base) var(--ease);
}

.page-about .about-team__card:hover,
.page-about .about-team__card:focus-within {
  transform: translateY(-2px);
  border-left-color: var(--c-amber);
  box-shadow: var(--shadow-1);
}

.page-about .about-team__code {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--c-green-ink);
  border-bottom: 1px solid rgba(23, 178, 106, .45);
  padding-bottom: 2px;
}

.page-about .about-team__card h3 {
  margin: 12px 0 8px;
  font-family: var(--font-head);
  font-size: var(--fs-20);
  font-weight: 700;
  line-height: 1.35;
  color: var(--c-ink);
}

.page-about .about-team__card p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.72;
  color: var(--c-text-soft);
}

/* ---------- 理由列表 ---------- */
.page-about .about-reasons {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: about-reason;
}

.page-about .about-reasons__item {
  counter-increment: about-reason;
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 0 14px;
  padding: 20px 0;
  border-top: 1px solid var(--c-line);
}

.page-about .about-reasons__item::before {
  content: counter(about-reason, decimal-leading-zero);
  grid-column: 1;
  grid-row: 1 / span 2;
  font-family: var(--font-mono);
  font-size: var(--fs-20);
  font-weight: 700;
  line-height: 1.3;
  color: var(--c-amber);
}

.page-about .about-reasons__item h3 {
  grid-column: 2;
  margin: 0;
  font-family: var(--font-head);
  font-size: var(--fs-20);
  font-weight: 700;
  line-height: 1.35;
  color: var(--c-ink);
}

.page-about .about-reasons__item p {
  grid-column: 2;
  margin: 7px 0 0;
  max-width: 64ch;
  font-size: var(--fs-16);
  line-height: 1.75;
  color: var(--c-text-soft);
}

/* ---------- 数据条 ---------- */
.page-about .about-statline {
  margin-top: 26px;
  padding: 20px 22px;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 16px;
  background: var(--c-navy);
  border-left: 3px solid var(--c-green);
  color: var(--c-on-dark);
}

.page-about .about-statline__num {
  font-family: var(--font-mono);
  font-size: var(--fs-40);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--c-amber);
}

.page-about .about-statline__txt {
  flex: 1 1 260px;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--c-on-dark-soft);
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  margin-top: clamp(44px, 6vw, 78px);
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

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

.page-about .about-next__card {
  display: block;
  padding: 18px;
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-left: 3px solid var(--c-silver);
  text-decoration: none;
  color: inherit;
  transition: transform var(--t-base) var(--ease), border-color var(--t-base) var(--ease), box-shadow var(--t-base) var(--ease);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  transform: translateY(-2px);
  border-left-color: var(--c-amber);
  box-shadow: var(--shadow-1);
}

.page-about .about-next__code {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--c-amber-ink);
}

.page-about .about-next__card h3 {
  margin: 10px 0 6px;
  font-family: var(--font-head);
  font-size: var(--fs-20);
  font-weight: 700;
  line-height: 1.35;
  color: var(--c-ink);
}

.page-about .about-next__card p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.7;
  color: var(--c-text-soft);
}

/* ---------- 焦点 ---------- */
.page-about a:focus-visible {
  outline: 2px solid var(--c-neon);
  outline-offset: 2px;
}

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

  .page-about .about-note:hover,
  .page-about .about-team__card:hover,
  .page-about .about-next__card:hover {
    transform: none;
  }
}