.page-about {
  --about-rail: 214px;
  --about-text: #C3CFE2;
  position: relative;
  background:
    radial-gradient(900px 620px at 10% 0%, rgba(255, 106, 31, 0.11), transparent 62%),
    radial-gradient(760px 520px at 92% 8%, rgba(22, 199, 154, 0.09), transparent 60%),
    var(--bg-base);
  color: var(--text);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about .mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  isolation: isolate;
  display: flex;
  align-items: flex-end;
  min-height: clamp(520px, 82vh, 760px);
  padding: clamp(72px, 12vh, 120px) 0 clamp(40px, 6vw, 64px);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-hero__bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 34%;
  opacity: 0.42;
}

.page-about .about-hero__veil {
  position: absolute;
  inset: 0;
  z-index: 1;
  background:
    linear-gradient(96deg, rgba(5, 10, 22, 0.97) 0%, rgba(5, 10, 22, 0.84) 40%, rgba(5, 10, 22, 0.34) 74%, rgba(5, 10, 22, 0.88) 100%),
    linear-gradient(180deg, rgba(5, 10, 22, 0.72) 0%, rgba(5, 10, 22, 0.12) 36%, rgba(5, 10, 22, 0.95) 100%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 2;
  width: 100%;
  max-width: min(760px, 100%);
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: clamp(28px, 5vw, 52px);
}

.page-about .about-hero__eyebrow {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--signal-soft);
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(34px, 5.6vw, 66px);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: 0.01em;
  color: var(--white);
  text-wrap: balance;
}

.page-about .about-hero__lede {
  max-width: 60ch;
  margin: clamp(18px, 3vw, 26px) 0 0;
  font-size: clamp(16px, 1.5vw, 18px);
  line-height: 1.8;
  color: var(--about-text);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 4vw, 34px);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(30px, 5vw, 46px) 0 0;
  padding: 1px;
  background: var(--line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-stat {
  padding: 14px 18px 16px;
  background: rgba(11, 20, 36, 0.88);
}

.page-about .about-stat dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--text-muted);
}

.page-about .about-stat dd {
  margin: 8px 0 0;
  font-size: 30px;
  line-height: 1;
  color: var(--white);
}

.page-about .about-stat dd span {
  margin-left: 2px;
  font-size: 13px;
  color: var(--text-muted);
}

/* ---------- 主体框架 ---------- */

.page-about .about-body {
  padding: clamp(48px, 7vw, 96px) 0 clamp(64px, 9vw, 120px);
}

.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
  align-items: start;
}

.page-about .about-rail__label {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--text-muted);
}

.page-about .about-rail__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-rail .index-link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(11, 20, 36, 0.72);
  color: var(--text-muted);
  font-size: 13px;
  line-height: 1.5;
  text-decoration: none;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .about-rail .index-link .mono {
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--line);
  transition: color 0.18s var(--ease);
}

.page-about .about-rail .index-link:hover {
  color: var(--text);
  border-color: rgba(255, 106, 31, 0.45);
}

.page-about .about-rail .index-link.is-current {
  color: var(--white);
  border-color: var(--signal);
  background: linear-gradient(120deg, rgba(255, 106, 31, 0.2), rgba(11, 20, 36, 0.75));
}

.page-about .about-rail .index-link.is-current .mono {
  color: var(--signal);
}

/* ---------- 章节 ---------- */

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

.page-about .about-section {
  padding-bottom: clamp(48px, 6vw, 76px);
  scroll-margin-top: 112px;
}

.page-about .about-section:last-child {
  padding-bottom: 0;
}

.page-about .about-section__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: clamp(20px, 3vw, 28px);
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}

.page-about .about-section__no {
  flex: none;
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--signal);
}

.page-about .about-section__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(23px, 3.2vw, 36px);
  font-weight: 600;
  line-height: 1.18;
  color: var(--text);
}

.page-about .about-section__text {
  max-width: 68ch;
  margin: 0 0 16px;
  font-size: 17px;
  line-height: 1.78;
  color: var(--about-text);
}

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

/* ---------- 01 角色 ---------- */

.page-about .about-roles {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 26px 0 0;
  padding: 1px;
  list-style: none;
  background: var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-role {
  padding: 20px 22px 22px;
  background: rgba(11, 20, 36, 0.92);
}

.page-about .about-role__dot {
  display: block;
  width: 26px;
  height: 3px;
  border-radius: 999px;
  margin-bottom: 14px;
}

.page-about .about-role__dot--signal { background: var(--signal); }
.page-about .about-role__dot--teal { background: var(--teal); }
.page-about .about-role__dot--warn { background: var(--warn); }

.page-about .about-role__title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text);
}

.page-about .about-role__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--text-muted);
}

/* ---------- 02 时间线分段 ---------- */

.page-about .about-timeline {
  margin-top: 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(11, 20, 36, 0.62);
  overflow: hidden;
}

.page-about .about-timeline .about-timeline__list {
  display: flex;
  gap: 0;
  padding: 0;
  border-bottom: 1px solid var(--line);
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-timeline .about-timeline__tab {
  flex: 0 0 auto;
  display: flex;
  flex-direction: column;
  gap: 5px;
  min-width: 132px;
  margin: 0;
  padding: 16px 22px 15px;
  border: 0;
  border-bottom: 2px solid transparent;
  border-radius: 0;
  background: transparent;
  color: var(--text-muted);
  text-align: left;
  cursor: pointer;
  transition: color 0.18s var(--ease), background 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .about-timeline .about-timeline__tab:hover {
  color: var(--text);
  background: rgba(30, 44, 73, 0.5);
}

.page-about .about-timeline .about-timeline__tab.is-active,
.page-about .about-timeline .about-timeline__tab[aria-selected="true"] {
  color: var(--white);
  border-bottom-color: var(--signal);
  background: linear-gradient(180deg, rgba(255, 106, 31, 0.14), transparent);
}

.page-about .about-timeline__year {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--signal-soft);
}

.page-about .about-timeline__tab.is-active .about-timeline__year,
.page-about .about-timeline .about-timeline__tab[aria-selected="true"] .about-timeline__year {
  color: var(--signal);
}

.page-about .about-timeline__ver {
  font-size: 15px;
  font-weight: 600;
  white-space: nowrap;
}

.page-about .about-timeline__panels {
  padding: clamp(22px, 3vw, 32px);
}

.page-about .about-timeline__panel + .about-timeline__panel {
  margin-top: 0;
}

.page-about .about-timeline__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(19px, 2.4vw, 25px);
  font-weight: 600;
  line-height: 1.28;
  color: var(--text);
}

.page-about .about-timeline__panel .about-section__text {
  margin-bottom: 18px;
  font-size: 16px;
}

/* ---------- 03 团队 ---------- */

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

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

.page-about .about-team__media img {
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.page-about .about-bars {
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 18px;
}

.page-about .about-bar__top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 8px;
}

.page-about .about-bar__name {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

.page-about .about-bar__num {
  font-size: 22px;
  line-height: 1;
  color: var(--white);
}

.page-about .about-bar__track {
  display: block;
  height: 6px;
  border-radius: 999px;
  background: rgba(30, 44, 73, 0.9);
  overflow: hidden;
}

.page-about .about-bar__fill {
  display: block;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--teal-deep), var(--teal));
}

.page-about .about-bar__fill--a { width: 42.8%; }
.page-about .about-bar__fill--b { width: 28.6%; background: linear-gradient(90deg, rgba(255, 106, 31, 0.55), var(--signal)); }
.page-about .about-bar__fill--c { width: 21.4%; }
.page-about .about-bar__fill--d { width: 7.2%; background: linear-gradient(90deg, rgba(255, 194, 75, 0.4), var(--warn)); }

.page-about .about-bar__desc {
  margin: 10px 0 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-muted);
}

/* ---------- 04 栏目矩阵 ---------- */

.page-about .about-columns {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
  margin-top: 26px;
}

.page-about .about-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 22px 22px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(160deg, rgba(30, 44, 73, 0.5), rgba(11, 20, 36, 0.85));
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .about-col:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 106, 31, 0.42);
}

.page-about .about-col .tag {
  align-self: flex-start;
}

.page-about .about-col__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.3;
  color: var(--text);
}

.page-about .about-col__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--text-muted);
}

.page-about .about-col__meta {
  margin: auto 0 0;
  padding-top: 12px;
  border-top: 1px dashed rgba(30, 44, 73, 0.9);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--signal-soft);
}

/* ---------- 05 数据处理步骤 ---------- */

.page-about .about-steps {
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  position: relative;
  display: grid;
  gap: 1px;
  background: var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-step {
  display: flex;
  gap: 18px;
  padding: 22px;
  background: rgba(11, 20, 36, 0.92);
}

.page-about .about-step__no {
  flex: none;
  width: 38px;
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--teal);
}

.page-about .about-step__title {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text);
}

.page-about .about-step__body p {
  max-width: 62ch;
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--text-muted);
}

/* ---------- 06 合作生态 ---------- */

.page-about .about-section--partners .about-band {
  margin: 0 0 clamp(26px, 4vw, 40px);
}

.page-about .about-band img {
  width: 100%;
  height: auto;
  aspect-ratio: 7 / 4;
  object-fit: cover;
}

.page-about .about-partner-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 26px;
  padding: 1px;
  background: var(--line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-partner-stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 20px 20px;
  background: rgba(11, 20, 36, 0.92);
}

.page-about .about-partner-stat__value {
  font-size: clamp(28px, 4vw, 40px);
  line-height: 1;
  color: var(--white);
}

.page-about .about-partner-stat__value span {
  font-size: 18px;
  color: var(--signal);
}

.page-about .about-partner-stat__label {
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--text-muted);
}

/* ---------- 07 下一步 ---------- */

.page-about .about-next {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
  margin-top: 26px;
}

.page-about .about-next__card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 24px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(11, 20, 36, 0.78);
  color: inherit;
  text-decoration: none;
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .about-next__card:hover {
  transform: translateY(-4px);
  border-color: var(--signal);
  background: linear-gradient(150deg, rgba(255, 106, 31, 0.14), rgba(11, 20, 36, 0.9));
}

.page-about .about-next__no {
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--signal);
}

.page-about .about-next__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 600;
  line-height: 1.3;
  color: var(--white);
}

.page-about .about-next__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--text-muted);
}

.page-about .about-next__go {
  margin-top: 4px;
  font-size: 14px;
  font-weight: 600;
  color: var(--signal-soft);
}

.page-about .about-next__go::after {
  content: " →";
}

.page-about .about-note {
  max-width: 66ch;
  margin: 24px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--line);
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-muted);
}

.page-about .about-note a {
  color: var(--teal);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-note a:hover {
  color: var(--signal-soft);
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .about-columns {
    grid-template-columns: repeat(12, minmax(0, 1fr));
  }

  .page-about .about-col--w7 { grid-column: span 7; }
  .page-about .about-col--w5 { grid-column: span 5; }
  .page-about .about-col--w4 { grid-column: span 4; }

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

  .page-about .about-partner-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(32px, 4vw, 56px);
  }

  .page-about .about-rail {
    position: sticky;
    top: 112px;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
  }

  .page-about .about-rail .index-link {
    display: flex;
    width: 100%;
    padding: 9px 12px;
    border: 0;
    border-left: 2px solid transparent;
    border-radius: 0 10px 10px 0;
    background: transparent;
    white-space: nowrap;
  }

  .page-about .about-rail .index-link:hover {
    background: rgba(30, 44, 73, 0.45);
  }

  .page-about .about-rail .index-link.is-current {
    border-left-color: var(--signal);
    background: linear-gradient(90deg, rgba(255, 106, 31, 0.18), transparent);
  }

  .page-about .about-team {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: clamp(28px, 3.5vw, 48px);
  }

  .page-about .about-section__title {
    max-width: 26ch;
  }
}

@media (min-width: 1140px) {
  .page-about .about-timeline__panels {
    padding: 34px 36px 36px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-col,
  .page-about .about-next__card,
  .page-about .about-rail .index-link {
    transition: none;
  }

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