.page-about {
  --about-pad: clamp(22px, 4vw, 44px);
  --about-gap: clamp(26px, 4.5vw, 56px);
  background:
    radial-gradient(1200px 640px at 92% -12%, rgba(198, 255, 61, 0.13), transparent 62%),
    radial-gradient(900px 520px at -8% 28%, rgba(59, 167, 255, 0.10), transparent 64%),
    var(--ink);
  color: var(--white);
  padding-bottom: clamp(48px, 8vw, 96px);
  overflow-x: clip;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-display);
  letter-spacing: -0.015em;
  color: var(--white);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-top: clamp(16px, 2.5vw, 28px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(22px, 4vw, 40px);
  margin-top: clamp(18px, 3vw, 30px);
  align-items: end;
}

.page-about .about-hero__lede h1 {
  font-size: clamp(2.1rem, 6.4vw, 4.4rem);
  line-height: 0.98;
  margin: 12px 0 18px;
  max-width: 16ch;
}

.page-about .about-hero__intro {
  color: #d7e4dc;
  line-height: 1.78;
  font-size: clamp(0.95rem, 1.6vw, 1.05rem);
  max-width: 40rem;
  margin: 0 0 24px;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-hero__shot figcaption {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
  font-size: 0.82rem;
  color: var(--muted);
  line-height: 1.6;
}

.page-about .about-shot {
  margin: 0;
  min-width: 0;
}

.page-about .about-shot__frame {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--panel);
}

.page-about .about-shot__frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(198, 255, 61, 0.12) 1px, transparent 1px),
    linear-gradient(90deg, rgba(198, 255, 61, 0.12) 1px, transparent 1px);
  background-size: 44px 44px;
  mix-blend-mode: screen;
  opacity: 0.55;
}

.page-about .about-shot img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-shot--wide figcaption,
.page-about .about-shot--square figcaption {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
  font-size: 0.82rem;
  color: var(--muted);
  line-height: 1.6;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(26px, 4vw, 44px) 0 0;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .about-stat {
  background: var(--panel);
  padding: 16px 18px;
}

.page-about .about-stat dt {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 6px;
}

.page-about .about-stat dd {
  margin: 0;
  font-size: 1.05rem;
  color: var(--white);
}

.page-about .about-stat dd .num {
  font-size: 1.7rem;
  color: var(--lime);
  margin-right: 4px;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: var(--about-gap);
  margin-top: clamp(36px, 6vw, 72px);
}

.page-about .about-index {
  display: none;
}

.page-about .about-chapters {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: clamp(16px, 2.6vw, 26px);
}

/* ---------- 面板 ---------- */
.page-about .about-chapter {
  position: relative;
  background: linear-gradient(170deg, rgba(12, 42, 32, 0.95), rgba(10, 33, 26, 0.95));
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: var(--about-pad);
  scroll-margin-top: 92px;
  box-shadow: 0 30px 70px -52px rgba(0, 0, 0, 0.95);
}

.page-about .about-chapter .section-head {
  margin-bottom: clamp(16px, 3vw, 26px);
}

.page-about .about-chapter .section-head__index {
  color: var(--lime);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
}

.page-about .about-chapter h2 {
  font-size: clamp(1.4rem, 3.4vw, 2.3rem);
  line-height: 1.08;
  margin: 8px 0 0;
  max-width: 22ch;
}

.page-about .about-chapter h3 {
  font-size: clamp(1rem, 1.7vw, 1.14rem);
  line-height: 1.3;
  margin: 0 0 6px;
}

.page-about .about-chapter p {
  color: #cfded5;
  line-height: 1.78;
  font-size: 0.95rem;
  margin: 0 0 12px;
}

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

.page-about .prose a,
.page-about .about-chapter__tail a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(59, 167, 255, 0.4);
  transition: color 0.16s var(--ease), border-color 0.16s var(--ease);
}

.page-about .prose a:hover,
.page-about .about-chapter__tail a:hover {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

.page-about .about-chapter__lead {
  color: var(--muted) !important;
  font-size: 0.9rem;
  max-width: 38ch;
}

.page-about .about-chapter__tail {
  margin-top: 18px !important;
  font-size: 0.88rem !important;
  color: var(--muted) !important;
}

/* ---------- 引言块 ---------- */
.page-about .about-pull {
  margin-top: clamp(18px, 3vw, 28px);
  padding: 18px 20px 18px 22px;
  border-left: 3px solid var(--lime);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  background: rgba(198, 255, 61, 0.06);
}

.page-about .about-pull__text {
  font-family: var(--font-display);
  font-size: clamp(1.15rem, 2.6vw, 1.55rem);
  line-height: 1.32;
  color: var(--white) !important;
  margin: 0 0 8px !important;
}

.page-about .about-pull__note {
  font-size: 0.86rem !important;
  color: var(--muted) !important;
  margin: 0 !important;
}

/* ---------- 工作流 ---------- */
.page-about .flow {
  list-style: none;
  margin: 0 0 clamp(20px, 3vw, 30px);
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.page-about .flow__step {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
  position: relative;
}

.page-about .flow__step:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .flow__no {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 1px solid var(--line);
  color: var(--lime);
  font-size: 0.78rem;
  background: rgba(6, 26, 20, 0.6);
  transition: border-color 0.16s var(--ease), background 0.16s var(--ease);
}

.page-about .flow__step:hover .flow__no {
  border-color: var(--lime);
  background: rgba(198, 255, 61, 0.12);
}

.page-about .flow__body p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--muted);
}

/* ---------- 时间线 ---------- */
.page-about .timeline-layout {
  display: grid;
  gap: clamp(22px, 4vw, 34px);
  align-items: start;
}

.page-about .timeline {
  position: relative;
  min-width: 0;
}

.page-about .timeline__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 18px;
  position: relative;
}

.page-about .timeline__list::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--blue), var(--lime) 55%, var(--orange));
  opacity: 0.75;
}

.page-about .timeline__item {
  position: relative;
  padding-left: 34px;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 2px solid var(--lime);
  background: var(--ink);
  box-shadow: 0 0 0 4px rgba(198, 255, 61, 0.08);
  transition: box-shadow 0.16s var(--ease), border-color 0.16s var(--ease);
}

.page-about .timeline__item:hover::before {
  border-color: var(--blue);
  box-shadow: 0 0 0 6px rgba(59, 167, 255, 0.16);
}

.page-about .timeline__season {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--yellow);
  margin: 0 0 4px !important;
}

.page-about .timeline__ver {
  font-size: clamp(1rem, 1.7vw, 1.1rem);
  margin: 0 0 4px !important;
  color: var(--white);
}

.page-about .timeline__desc {
  font-size: 0.88rem !important;
  color: var(--muted) !important;
  margin: 0 !important;
}

.page-about .about-shot--square {
  max-width: 320px;
  justify-self: start;
}

/* ---------- 覆盖力量 ---------- */
.page-about .cover {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.page-about .cover__row {
  display: grid;
  grid-template-columns: minmax(64px, auto) minmax(0, 1fr);
  align-items: baseline;
  gap: clamp(14px, 3vw, 30px);
  padding: 18px 0;
  border-top: 1px solid var(--line);
}

.page-about .cover__row:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .cover__num {
  font-size: clamp(2.2rem, 6vw, 3.4rem);
  line-height: 1;
  color: var(--lime);
  display: block;
  transition: color 0.16s var(--ease);
}

.page-about .cover__row:nth-child(2) .cover__num {
  color: var(--blue);
}

.page-about .cover__row:nth-child(3) .cover__num {
  color: var(--orange);
}

.page-about .cover__text h3 {
  font-size: clamp(0.98rem, 1.8vw, 1.1rem);
  margin-bottom: 6px;
}

.page-about .cover__text p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--muted);
}

/* ---------- 四条标准 ---------- */
.page-about .criteria {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .criteria__item {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
  transition: background 0.16s var(--ease);
}

.page-about .criteria__item:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .criteria__item:hover {
  background: rgba(59, 167, 255, 0.05);
}

.page-about .criteria__no {
  font-size: 0.8rem;
  color: var(--blue);
  padding-top: 4px;
}

.page-about .criteria__body p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--muted);
}

/* ---------- 团队协作 ---------- */
.page-about .about-chapter__split {
  display: grid;
  gap: clamp(20px, 3.5vw, 30px);
}

.page-about .about-facts {
  background: var(--stripe);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 18px 20px;
}

.page-about .about-facts .label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 4px;
}

.page-about .about-facts__value {
  margin: 0 0 14px !important;
  font-size: 0.92rem !important;
  color: var(--white) !important;
  line-height: 1.6 !important;
}

.page-about .about-facts__value:last-child {
  margin-bottom: 0 !important;
}

/* ---------- 合作切换 ---------- */
.page-about .collab {
  position: relative;
  margin-top: 6px;
}

.page-about .collab__radio {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

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

.page-about .collab__tabs label {
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  padding: 9px 16px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.85rem;
  transition: color 0.16s var(--ease), border-color 0.16s var(--ease), background 0.16s var(--ease);
}

.page-about .collab__tabs label:hover {
  color: var(--white);
  border-color: var(--blue);
}

.page-about #collab-media:checked ~ .collab__tabs label[for="collab-media"],
.page-about #collab-youth:checked ~ .collab__tabs label[for="collab-youth"],
.page-about #collab-data:checked ~ .collab__tabs label[for="collab-data"] {
  background: var(--lime);
  border-color: var(--lime);
  color: var(--ink);
}

.page-about .collab__panel {
  display: none;
  padding: 18px 0 0;
}

.page-about #collab-media:checked ~ .collab__panels .collab__panel:nth-child(1),
.page-about #collab-youth:checked ~ .collab__panels .collab__panel:nth-child(2),
.page-about #collab-data:checked ~ .collab__panels .collab__panel:nth-child(3) {
  display: block;
}

.page-about .collab__panel h3 {
  color: var(--lime);
}

.page-about .collab__panel p {
  margin: 0;
  max-width: 44ch;
}

.page-about .about-cta {
  margin-top: clamp(22px, 3.5vw, 32px);
  padding-top: clamp(18px, 3vw, 26px);
  border-top: 1px solid var(--line);
  display: grid;
  gap: 16px;
}

.page-about .about-cta p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--muted);
  max-width: 46ch;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 760px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-chapter__split {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr);
    align-items: start;
  }

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: clamp(28px, 4vw, 52px);
  }

  .page-about .timeline-layout {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 0.5fr);
  }

  .page-about .about-shot--square {
    max-width: none;
  }

  .page-about .flow__step {
    grid-template-columns: 60px minmax(0, 1fr);
    gap: 18px;
  }

  .page-about .criteria__item {
    grid-template-columns: 56px minmax(0, 1fr);
  }
}

@media (min-width: 1120px) {
  .page-about .about-body {
    grid-template-columns: 92px minmax(0, 1fr);
    gap: clamp(24px, 3vw, 46px);
    align-items: start;
  }

  .page-about .about-index {
    display: block;
    position: sticky;
    top: 112px;
  }

  .page-about .about-index__title {
    font-family: var(--font-mono);
    font-size: 0.66rem;
    letter-spacing: 0.18em;
    color: var(--muted);
    margin: 0 0 10px;
  }

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

  .page-about .about-index__link {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 9px 8px;
    border-left: 2px solid var(--line);
    color: var(--muted);
    text-decoration: none;
    font-size: 0.8rem;
    transition: color 0.16s var(--ease), border-color 0.16s var(--ease), transform 0.16s var(--ease);
  }

  .page-about .about-index__link .num {
    font-size: 0.68rem;
    opacity: 0.8;
  }

  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible {
    color: var(--lime);
    border-left-color: var(--lime);
    transform: translateX(3px);
  }

  .page-about .about-chapter:nth-child(even) {
    margin-left: clamp(18px, 3.5vw, 48px);
  }

  .page-about .about-chapter:nth-child(3n) {
    margin-right: clamp(14px, 2.5vw, 34px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .flow__no,
  .page-about .timeline__item::before,
  .page-about .cover__num,
  .page-about .criteria__item,
  .page-about .collab__tabs label {
    transition: none;
  }

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