.page-about {
  --about-paper-rule: rgba(42, 33, 28, .18);
  --about-paper-soft: rgba(42, 33, 28, .70);
  --about-paper-em: #A8501F;
  --about-line-soft: rgba(124, 137, 173, .24);
  --about-line-mid: rgba(124, 137, 173, .38);
  --about-body-soft: rgba(245, 247, 255, .78);

  background: var(--ink-night);
  color: var(--white);
  padding-bottom: 72px;
}

/* ---------- 页首 ---------- */
.page-about .about-head {
  padding: 28px 0 0;
}

.page-about .about-head .eyebrow {
  margin: 26px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--cyan);
}

.page-about .about-head h1 {
  margin: 12px 0 0;
  max-width: 17em;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(27px, 5.8vw, 44px);
  line-height: 1.18;
  letter-spacing: -0.01em;
}

.page-about .about-head .lede {
  margin: 20px 0 0;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--about-body-soft);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin: 34px 0 0;
  padding: 0;
  border-top: var(--line);
  border-left: var(--line);
}

.page-about .about-facts__cell {
  padding: 15px 16px 17px;
  border-right: var(--line);
  border-bottom: var(--line);
}

.page-about .about-facts__cell dt {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--mist);
}

.page-about .about-facts__cell dd {
  margin: 9px 0 0;
  font-family: var(--font-mono);
  font-size: 19px;
  letter-spacing: .06em;
  color: var(--gold);
}

.page-about .about-index {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 22px;
  margin: 30px 0 0;
  padding: 14px 0 0;
  border-top: var(--line);
}

.page-about .about-index__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--mist);
}

.page-about .about-index__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-index__link {
  display: inline-block;
  font-size: 13px;
  color: var(--white);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .about-index__link .num {
  margin-right: 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--mist);
  transition: color 160ms var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .about-index__link:hover .num,
.page-about .about-index__link:focus-visible .num {
  color: var(--gold);
}

/* ---------- 时间轴骨架 ---------- */
.page-about .about-body {
  padding: 50px 0 0;
}

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

.page-about .tl__item {
  position: relative;
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  column-gap: 14px;
  padding-bottom: 44px;
}

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: 22px;
  top: 0;
  bottom: 0;
  width: 1px;
  background: var(--about-line-soft);
}

.page-about .tl__item:last-child::before {
  display: none;
}

.page-about .tl__item:last-child {
  padding-bottom: 8px;
}

.page-about .tl__mark {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 9px;
  padding-top: 2px;
}

.page-about .tl__num {
  padding: 2px 4px;
  background: var(--ink-night);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--mist);
  transition: color 160ms var(--ease);
}

.page-about .tl__dot {
  width: 9px;
  height: 9px;
  border: 1px solid var(--mist);
  border-radius: 50%;
  background: var(--ink-night);
  transition: background-color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .tl__item:hover .tl__num,
.page-about .tl__item:focus-within .tl__num {
  color: var(--gold);
}

.page-about .tl__item:hover .tl__dot,
.page-about .tl__item:focus-within .tl__dot {
  border-color: var(--gold);
  background: var(--gold);
}

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

.page-about .tl__kicker {
  margin: 0 0 9px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--cyan);
}

.page-about .tl__title {
  margin: 0 0 18px;
  max-width: 22em;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(21px, 4.4vw, 30px);
  line-height: 1.28;
  letter-spacing: -0.01em;
}

/* ---------- 面板 ---------- */
.page-about .tl__panel {
  padding: 22px 18px;
}

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

.page-about .tl__panel--dark {
  background: var(--ink-slate);
  border: var(--line);
  box-shadow: var(--shadow-in);
}

.page-about .tl__panel p {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.85;
}

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

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

.page-about .tl__lead {
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-body-soft);
}

.page-about .tl__tail {
  margin: 20px 0 0;
  padding-top: 16px;
  border-top: var(--line);
  font-size: 14px;
  line-height: 1.78;
  color: var(--about-body-soft);
}

.page-about .tl__panel--paper .tl__tail {
  border-top: var(--about-paper-rule);
  color: var(--about-paper-soft);
}

.page-about .tl__sub {
  margin: 0 0 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: .14em;
  color: var(--about-paper-em);
}

.page-about .tl__sub--gap {
  margin-top: 26px;
}

.page-about .tl__link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 160ms var(--ease), color 160ms var(--ease);
}

.page-about .tl__link:hover,
.page-about .tl__link:focus-visible {
  border-bottom-color: var(--cyan);
}

.page-about .tl__link--dark {
  color: var(--about-paper-em);
  border-bottom-color: rgba(168, 80, 31, .35);
}

.page-about .tl__link--dark:hover,
.page-about .tl__link--dark:focus-visible {
  border-bottom-color: var(--about-paper-em);
}

/* ---------- 两条主线 ---------- */
.page-about .lines {
  display: grid;
  gap: 20px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .lines__item {
  padding-top: 16px;
  border-top: var(--line);
}

.page-about .lines__title {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.4;
  color: var(--white);
}

.page-about .lines__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--about-body-soft);
}

/* ---------- 岗位与人数 ---------- */
.page-about .roles {
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .roles__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas:
    "name count"
    "desc count";
  align-items: center;
  gap: 4px 16px;
  padding: 14px 0;
  border-bottom: var(--about-paper-rule);
}

.page-about .roles__row:first-child {
  border-top: var(--about-paper-rule);
}

.page-about .roles__name {
  grid-area: name;
  font-size: 15px;
  font-weight: 600;
  color: var(--paper-ink);
}

.page-about .roles__desc {
  grid-area: desc;
  font-size: 13.5px;
  line-height: 1.66;
  color: var(--about-paper-soft);
}

.page-about .roles__count {
  grid-area: count;
  font-family: var(--font-mono);
  font-size: 22px;
  letter-spacing: .06em;
  color: var(--about-paper-em);
}

/* ---------- 复核步骤 ---------- */
.page-about .check {
  display: grid;
  gap: 12px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .check__item {
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
}

.page-about .check__idx {
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--about-paper-em);
}

.page-about .check__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--paper-ink);
}

/* ---------- 版本刻度 ---------- */
.page-about .vscale {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .vscale__item {
  position: relative;
  padding: 16px 14px 18px 0;
  border-top: var(--line-strong);
}

.page-about .vscale__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: -5px;
  width: 1px;
  height: 10px;
  background: var(--mist);
}

.page-about .vscale__ver {
  display: block;
  font-family: var(--font-mono);
  font-size: 16px;
  letter-spacing: .08em;
  color: var(--cyan);
}

.page-about .vscale__note {
  display: block;
  margin-top: 8px;
  font-size: 13.5px;
  line-height: 1.68;
  color: var(--about-body-soft);
}

/* ---------- 口径双栏 ---------- */
.page-about .spec {
  display: grid;
  gap: 16px;
}

.page-about .spec__col {
  padding: 18px 18px 20px;
  background: var(--ink-night);
  border: var(--line);
  border-left: 2px solid var(--cyan);
}

.page-about .spec__col--limit {
  border-left-color: var(--mist);
}

.page-about .spec__title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: .14em;
  color: var(--cyan);
}

.page-about .spec__col--limit .spec__title {
  color: var(--mist);
}

.page-about .spec__list {
  display: grid;
  gap: 10px;
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .spec__list li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.78;
  color: var(--about-body-soft);
}

.page-about .spec__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 8px;
  height: 1px;
  background: var(--cyan);
}

.page-about .spec__col--limit .spec__list li::before {
  background: var(--mist);
}

/* ---------- 配图 ---------- */
.page-about .about-figure {
  margin: 20px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  border: var(--line);
  background: var(--ink-slate);
}

.page-about .about-figure--band img {
  height: 190px;
  object-fit: cover;
}

.page-about .about-figure .media__caption {
  display: block;
  margin-top: 9px;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: .02em;
  color: var(--mist);
}

/* ---------- 收束 ---------- */
.page-about .about-close {
  margin-top: 44px;
  padding-top: 22px;
  border-top: var(--line);
}

.page-about .about-close__text {
  margin: 0;
  max-width: 40em;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--about-body-soft);
}

.page-about .about-close__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .lines {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0 30px;
  }

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

  .page-about .vscale {
    grid-template-columns: 1.1fr 1.5fr 1fr 1.3fr;
  }

  .page-about .about-figure--band img {
    height: 240px;
  }

  .page-about .tl__panel {
    padding: 26px 26px;
  }
}

@media (min-width: 1000px) {
  .page-about .about-head {
    padding-top: 42px;
  }

  .page-about .about-body {
    padding-top: 66px;
  }

  .page-about .tl__item {
    grid-template-columns: 72px minmax(0, 1fr);
    column-gap: 26px;
    padding-bottom: 62px;
  }

  .page-about .tl__item::before {
    left: 36px;
  }

  .page-about .tl__content {
    max-width: 900px;
  }

  .page-about .tl__panel {
    padding: 32px 36px;
  }

  .page-about .about-figure--band img {
    height: 280px;
  }

  .page-about .about-close {
    margin-top: 56px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .about-index__link .num,
  .page-about .tl__num,
  .page-about .tl__dot,
  .page-about .tl__link {
    transition: none;
  }
}