.page-about {
  --about-rail: 196px;
  --about-gap: 56px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 72px 0 52px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -34%;
  right: -18%;
  width: 72%;
  height: 190%;
  background:
    linear-gradient(138deg, rgba(53, 224, 212, 0.16), rgba(53, 224, 212, 0) 46%),
    linear-gradient(318deg, rgba(255, 61, 139, 0.15), rgba(255, 178, 77, 0) 52%);
  transform: rotate(-9deg);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--cyan-400), var(--magenta-500) 62%, transparent);
  opacity: 0.5;
}

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

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(34px, 7vw, 60px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--text-100);
  max-width: 15ch;
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  color: var(--text-400);
  line-height: 1.75;
}

.page-about .about-stats {
  list-style: none;
  margin: 36px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--line-800);
  border: 1px solid var(--line-800);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-stats li {
  background: var(--night-900);
  padding: 18px 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-stats .stat-num {
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1;
  color: var(--accent);
}

.page-about .about-stats .stat-label {
  font-size: 13px;
  color: var(--text-400);
  letter-spacing: 0.02em;
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  padding: 8px 0 0;
}

.page-about .about-body__inner {
  display: block;
}

.page-about .about-index {
  margin: 40px 0 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line-800);
}

.page-about .about-index__caption {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-400);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-index__list a {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 9px 12px;
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
  color: var(--text-400);
  text-decoration: none;
  font-size: 14px;
  line-height: 1.5;
  transition: color 0.18s var(--ease), background 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  color: var(--text-100);
  background: var(--glass-bg);
  border-left-color: var(--accent);
}

.page-about .about-index__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--accent);
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding-top: 52px;
  scroll-margin-top: calc(var(--topbar-h) + 28px);
}

.page-about .about-chapter + .about-chapter {
  margin-top: 56px;
  border-top: 1px solid var(--line-800);
}

.page-about .about-chapter__head {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .about-chapter__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--accent);
}

.page-about .about-chapter__title {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(24px, 4.6vw, 34px);
  line-height: 1.28;
  letter-spacing: -0.01em;
  color: var(--text-100);
}

.page-about .about-chapter__lede {
  margin: 18px 0 0;
  color: var(--text-400);
  line-height: 1.78;
}

.page-about .about-chapter__note {
  margin: 20px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-400);
  padding-left: 14px;
  border-left: 2px solid var(--accent);
}

.page-about .about-chapter__note a,
.page-about .about-steady__link a {
  color: var(--accent-soft);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 做 / 不做 ---------- */
.page-about .about-duo {
  margin-top: 30px;
  display: grid;
  gap: 16px;
}

.page-about .about-duo__col {
  position: relative;
  padding: 22px 20px 24px;
  border: 1px solid var(--line-800);
  border-radius: var(--radius);
  background: var(--night-900);
}

.page-about .about-duo__col--yes {
  border-top: 2px solid var(--ok-400);
}

.page-about .about-duo__col--no {
  border-top: 2px solid var(--warn-400);
}

.page-about .about-duo__title {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--text-100);
}

.page-about .about-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-list li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-100);
}

.page-about .about-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 10px;
  height: 2px;
  background: var(--ok-400);
}

.page-about .about-list--no li::before {
  background: var(--warn-400);
}

.page-about .about-list--plain li::before {
  top: 12px;
  width: 8px;
  background: var(--accent);
}

.page-about .about-list strong {
  color: var(--accent-soft);
  font-weight: 600;
}

/* ---------- 分栏：文字 + 图 ---------- */
.page-about .about-split {
  margin-top: 30px;
  display: grid;
  gap: 28px;
}

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

.page-about .about-split__media {
  margin: 0;
}

.page-about .about-split__media .media-frame {
  border-radius: var(--radius);
}

.page-about .about-sub {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  letter-spacing: -0.01em;
  color: var(--text-100);
}

/* ---------- 定义列表 ---------- */
.page-about .about-defs {
  margin: 24px 0 0;
  border-top: 1px solid var(--line-800);
}

.page-about .about-defs__row {
  display: grid;
  gap: 6px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line-800);
}

.page-about .about-defs__row dt {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.01em;
  color: var(--accent-soft);
}

.page-about .about-defs__row dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-400);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline-media {
  margin: 30px 0 0;
}

.page-about .about-timeline-media .media-frame {
  border-radius: var(--radius);
}

.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 36px 0 0;
  padding: 0 0 0 32px;
  display: grid;
  gap: 26px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--cyan-400), var(--magenta-500) 58%, var(--amber-400));
  opacity: 0.7;
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  transition: border-color 0.18s var(--ease), transform 0.18s var(--ease);
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -32px;
  top: 7px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink-950);
  border: 2px solid var(--cyan-400);
}

.page-about .about-timeline__item:nth-child(2)::before {
  border-color: var(--cyan-400);
}

.page-about .about-timeline__item:nth-child(3)::before {
  border-color: var(--magenta-500);
}

.page-about .about-timeline__item:nth-child(4)::before {
  border-color: var(--amber-400);
}

.page-about .about-timeline__stage {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--text-100);
}

.page-about .about-timeline__text {
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-400);
}

.page-about .about-timeline__item:hover,
.page-about .about-timeline__item:focus-visible,
.page-about .about-timeline__item:focus-within {
  outline: none;
  border-color: var(--glass-line);
  background: var(--glass-bg);
  transform: translateX(2px);
  padding: 12px 14px;
}

/* ---------- 没有改变的事 ---------- */
.page-about .about-steady {
  margin-top: 36px;
  padding: 22px 20px 24px;
  border: 1px solid var(--line-800);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  background: var(--night-900);
}

.page-about .about-steady__title {
  margin: 0 0 16px;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 19px;
  line-height: 1.4;
  color: var(--text-100);
}

.page-about .about-steady__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-steady__list li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-400);
}

.page-about .about-steady__dot {
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--cyan-400), var(--magenta-500));
}

.page-about .about-steady__link {
  margin: 18px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-400);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line-800);
  border: 1px solid var(--line-800);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-team__item {
  background: var(--night-900);
  padding: 22px 20px 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .about-team__item .stat-num {
  font-family: var(--font-mono);
  font-size: 32px;
  font-weight: 600;
  line-height: 1;
  letter-spacing: 0.02em;
  background: linear-gradient(120deg, var(--magenta-500), var(--amber-400));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.page-about .about-team__role {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: -0.01em;
  color: var(--text-100);
}

.page-about .about-team__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--text-400);
}

/* ---------- 折叠组 ---------- */
.page-about .about-checks {
  margin-top: 28px;
}

.page-about .about-checks .expand-trigger {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
}

.page-about .about-checks .expand-panel p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--text-400);
}

.page-about .about-checks .expand-panel a {
  color: var(--accent-soft);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 口径提示 ---------- */
.page-about .about-note {
  margin-top: 28px;
  padding: 20px 20px 22px;
  border: 1px solid var(--line-800);
  border-radius: var(--radius);
  background: var(--night-900);
}

.page-about .about-note--warn {
  border-left: 3px solid var(--warn-400);
}

.page-about .about-note__label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--warn-400);
}

.page-about .about-note__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--text-400);
}

/* ---------- 地域 ---------- */
.page-about .about-region {
  margin: 28px 0 0;
  border-top: 1px solid var(--line-800);
}

.page-about .about-region__row {
  display: grid;
  gap: 6px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line-800);
}

.page-about .about-region__row dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--accent);
}

.page-about .about-region__row dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-100);
}

/* ---------- 结尾信息带 ---------- */
.page-about .about-next {
  margin-top: 72px;
  padding: 40px 0 52px;
  border-top: 1px solid var(--line-800);
  background:
    linear-gradient(180deg, rgba(26, 36, 64, 0.45), rgba(5, 7, 14, 0) 78%);
}

.page-about .about-next__title {
  margin: 0 0 22px;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(20px, 3.6vw, 26px);
  line-height: 1.35;
  color: var(--text-100);
}

.page-about .about-next__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line-800);
  border: 1px solid var(--line-800);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-next__list a {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 18px 20px;
  background: var(--night-900);
  text-decoration: none;
  transition: background 0.18s var(--ease), color 0.18s var(--ease);
}

.page-about .about-next__list a:hover,
.page-about .about-next__list a:focus-visible {
  background: var(--glass-800);
}

.page-about .about-next__label {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--text-100);
}

.page-about .about-next__hint {
  font-size: 13px;
  line-height: 1.65;
  color: var(--text-400);
}

.page-about .about-next__list a:hover .about-next__label,
.page-about .about-next__list a:focus-visible .about-next__label {
  color: var(--accent);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, 1fr);
  }

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

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

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

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 96px 0 60px;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: 36px;
    align-items: start;
  }

  .page-about .about-split--reverse {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
  }

  .page-about .about-split--reverse .about-split__media {
    order: -1;
  }

  .page-about .about-defs__row,
  .page-about .about-region__row {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 20px;
    align-items: baseline;
  }

  .page-about .about-timeline {
    padding: 30px 0 0;
    gap: 0 18px;
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-timeline::before {
    left: 0;
    right: 0;
    top: 6px;
    bottom: auto;
    width: auto;
    height: 2px;
    background: linear-gradient(90deg, var(--cyan-400), var(--magenta-500) 62%, var(--amber-400));
  }

  .page-about .about-timeline__item::before {
    left: 0;
    top: 0;
  }

  .page-about .about-timeline__item:hover,
  .page-about .about-timeline__item:focus-visible,
  .page-about .about-timeline__item:focus-within {
    transform: translateY(-3px);
  }

  .page-about .about-next__list {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (min-width: 1024px) {
  .page-about .about-body__inner {
    display: grid;
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: calc(var(--topbar-h) + 32px);
    margin: 40px 0 0;
    padding: 0 0 0 0;
    border-bottom: 0;
    align-self: start;
  }

  .page-about .about-index__list a {
    padding: 10px 10px 10px 12px;
  }

  .page-about .about-chapter {
    padding-top: 56px;
  }

  .page-about .about-chapter + .about-chapter {
    margin-top: 64px;
  }

  .page-about .about-next {
    margin-top: 96px;
    padding: 48px 0 64px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__list a,
  .page-about .about-timeline__item,
  .page-about .about-next__list a {
    transition: none;
  }

  .page-about .about-timeline__item:hover,
  .page-about .about-timeline__item:focus-visible,
  .page-about .about-timeline__item:focus-within {
    transform: none;
  }
}