.page-about {
  --about-rail: 214px;
  --about-gap: clamp(1.5rem, 4vw, 3.5rem);
  --about-radius: var(--radius-soft);
  background:
    radial-gradient(90% 60% at 100% 0%, rgba(34, 230, 216, 0.06), transparent 62%),
    var(--bg);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(1.4rem, 4vw, 2.6rem) var(--gutter) clamp(2rem, 4vw, 3rem);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero .breadcrumb {
  margin-bottom: 1.6rem;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.8rem, 5vw, 3.5rem);
  align-items: center;
  max-width: var(--shell);
  margin: 0 auto;
}

.page-about .about-hero__kicker {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.22em;
  color: var(--cyan);
  margin-bottom: 0.85rem;
}

.page-about .about-hero__kicker .mono {
  color: var(--orange);
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.1rem, 4.6vw, 4rem);
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin: 0 0 1.1rem;
  text-wrap: balance;
}

.page-about .about-hero__lede {
  max-width: 36em;
  color: var(--muted);
  font-size: clamp(0.95rem, 1.5vw, 1.06rem);
  line-height: 1.8;
  margin: 0;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 1.7rem;
}

.page-about .about-hero__visual {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
  background: linear-gradient(150deg, var(--blue-mid) 0%, var(--bg-2) 62%);
  padding: clamp(0.6rem, 1.6vw, 1.1rem);
  overflow: hidden;
}

.page-about .about-hero__visual::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(70% 60% at 70% 20%, rgba(34, 230, 216, 0.16), transparent 70%);
  pointer-events: none;
}

.page-about .about-hero__visual svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .about-facts {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(1.8rem, 4vw, 2.6rem) auto 0;
  padding: 0;
  max-width: var(--shell);
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-soft);
  overflow: hidden;
}

.page-about .about-facts li {
  background: var(--bg-2);
  padding: 1rem 1.1rem 1.15rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.page-about .about-facts__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.5rem, 3.6vw, 2.1rem);
  line-height: 1;
  color: var(--cyan);
  letter-spacing: -0.02em;
}

.page-about .about-facts li:nth-child(3) .about-facts__num,
.page-about .about-facts li:nth-child(4) .about-facts__num {
  color: var(--orange);
}

.page-about .about-facts__label {
  font-size: 0.8rem;
  line-height: 1.55;
  color: var(--muted);
}

/* ---------- 主栅格 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--about-gap);
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(2rem, 5vw, 3.4rem) var(--gutter) clamp(3rem, 7vw, 5rem);
}

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

/* ---------- 左侧索引 ---------- */
.page-about .about-rail {
  position: relative;
}

.page-about .about-rail .rail-title {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.24em;
  color: var(--muted);
  margin: 0 0 0.75rem;
}

.page-about .about-rail .rail-list {
  display: flex;
  gap: 0.45rem;
  overflow-x: auto;
  padding-bottom: 0.55rem;
  scrollbar-width: thin;
}

.page-about .about-rail .rail-link {
  flex: 0 0 auto;
  white-space: nowrap;
  font-size: 0.82rem;
  color: var(--muted);
  text-decoration: none;
  padding: 0.42rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--bg-2);
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.page-about .about-rail .rail-link:hover,
.page-about .about-rail .rail-link:focus-visible {
  color: var(--ink);
  border-color: var(--cyan);
  background: rgba(34, 230, 216, 0.09);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  scroll-margin-top: 5.5rem;
}

.page-about .about-sec + .about-sec {
  margin-top: clamp(3rem, 7vw, 5.5rem);
}

.page-about .about-sec .section-title {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.08;
  font-size: clamp(1.6rem, 3.4vw, 2.5rem);
  color: var(--ink);
  margin: 0.6rem 0 0.7rem;
  text-wrap: balance;
}

.page-about .about-sec .badge-index {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-sec .section-lede {
  max-width: 40em;
  color: var(--muted);
  line-height: 1.8;
  font-size: 0.94rem;
  margin: 0;
}

.page-about .about-prose {
  margin-top: 1.6rem;
}

.page-about .about-prose p {
  max-width: 40em;
  line-height: 1.85;
  color: rgba(242, 246, 255, 0.88);
  font-size: 0.95rem;
  margin: 0;
}

.page-about .about-prose p + p {
  margin-top: 1rem;
}

.page-about a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(34, 230, 216, 0.4);
  transition: border-color 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about a:hover,
.page-about a:focus-visible {
  color: var(--ink);
  border-bottom-color: var(--orange);
}

/* ---------- 团队分工 ---------- */
.page-about .crew-grid {
  margin-top: 1.8rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.9rem;
}

.page-about .crew-card {
  position: relative;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
  padding: 1.2rem 1.15rem 1.25rem;
  transition: transform 0.24s var(--ease), border-color 0.24s var(--ease);
}

.page-about .crew-card:hover,
.page-about .crew-card:focus-within {
  transform: translateY(-4px);
  border-color: var(--cyan);
}

.page-about .crew-card__idx {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--orange);
  margin: 0 0 0.6rem;
}

.page-about .crew-card__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.12rem;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin: 0 0 0.5rem;
}

.page-about .crew-card__text {
  font-size: 0.85rem;
  line-height: 1.75;
  color: var(--muted);
  margin: 0;
}

.page-about .crew-card__more {
  display: block;
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  font-size: 0.8rem;
  line-height: 1.7;
  color: rgba(242, 246, 255, 0.8);
  border-top: 1px solid var(--line);
  transition: max-height 0.32s var(--ease), opacity 0.32s var(--ease), margin-top 0.32s var(--ease), padding-top 0.32s var(--ease);
}

.page-about .crew-card:hover .crew-card__more,
.page-about .crew-card:focus-within .crew-card__more {
  max-height: 9rem;
  opacity: 1;
  margin-top: 0.85rem;
  padding-top: 0.75rem;
}

.page-about .crew-card__more-label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--lime);
  margin-right: 0.45rem;
}

@media (hover: none) {
  .page-about .crew-card__more {
    max-height: 9rem;
    opacity: 1;
    margin-top: 0.85rem;
    padding-top: 0.75rem;
  }
}

.page-about .about-figure {
  margin: 1.4rem 0 0;
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
  background: var(--bg-2);
  overflow: hidden;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 3 / 2;
  opacity: 0.9;
}

.page-about .about-figure figcaption {
  padding: 0.8rem 1.1rem 0.95rem;
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

/* ---------- 栏目体系 ---------- */
.page-about .column-list {
  list-style: none;
  counter-reset: none;
  margin: 1.8rem 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .column-list li {
  display: grid;
  grid-template-columns: 2.4rem minmax(0, 1fr);
  gap: 0.3rem 0.8rem;
  padding: 1rem 0.15rem 1.05rem;
  border-bottom: 1px solid var(--line);
  transition: background 0.2s var(--ease);
}

.page-about .column-list li:hover {
  background: rgba(34, 230, 216, 0.04);
}

.page-about .column-list__id {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--muted);
  padding-top: 0.2rem;
  font-variant-numeric: tabular-nums;
}

.page-about .column-list__name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: 0;
  color: var(--ink);
  margin: 0 0 0.3rem;
}

.page-about .column-list__desc {
  font-size: 0.84rem;
  line-height: 1.72;
  color: var(--muted);
  margin: 0;
}

/* ---------- 更新节奏 ---------- */
.page-about .about-split {
  margin-top: 1.8rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.4rem, 3vw, 2.4rem);
}

.page-about .about-split__subtitle {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.02rem;
  color: var(--cyan);
  letter-spacing: 0;
  margin: 0 0 0.5rem;
  padding-left: 0.7rem;
  border-left: 3px solid var(--cyan);
}

.page-about .about-split__subtitle + p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.82;
  color: rgba(242, 246, 255, 0.85);
}

.page-about .about-split__text > * + * {
  margin-top: 1.4rem;
}

.page-about .about-split__media {
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
  background: var(--bg-2);
  overflow: hidden;
  align-self: start;
}

.page-about .about-split__media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 10 / 7;
}

.page-about .about-split__cap {
  margin: 0;
  padding: 0.8rem 1.05rem 0.9rem;
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

/* ---------- 时间轴 ---------- */
.page-about .about-banner {
  margin-top: 1.8rem;
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
  overflow: hidden;
  background: var(--bg-2);
}

.page-about .about-banner img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 14 / 5;
  opacity: 0.85;
}

.page-about .about-timeline {
  position: relative;
  margin-top: 1.6rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), var(--orange) 60%, var(--line));
  opacity: 0.6;
}

.page-about .phase {
  position: relative;
  padding: 1.05rem 1.1rem 1.1rem 2.1rem;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
  transition: border-color 0.24s var(--ease), transform 0.24s var(--ease);
}

.page-about .phase::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 1.45rem;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--cyan);
}

.page-about .phase--key::before {
  background: var(--lime);
  border-color: var(--lime);
  box-shadow: 0 0 0 5px rgba(198, 255, 74, 0.16);
}

.page-about .phase:hover {
  border-color: var(--cyan);
  transform: translateY(-3px);
}

.page-about .phase__year {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--orange);
  margin: 0 0 0.45rem;
  font-variant-numeric: tabular-nums;
}

.page-about .phase__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.08rem;
  color: var(--ink);
  letter-spacing: -0.01em;
  margin: 0 0 0.45rem;
}

.page-about .phase__text {
  font-size: 0.84rem;
  line-height: 1.72;
  color: var(--muted);
  margin: 0 0 0.75rem;
}

.page-about .phase__fold {
  font-size: 0.8rem;
}

.page-about .phase__fold summary {
  cursor: pointer;
  color: var(--cyan);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  list-style: none;
}

.page-about .phase__fold summary::-webkit-details-marker {
  display: none;
}

.page-about .phase__fold summary::after {
  content: " ＋";
  font-size: 0.72rem;
}

.page-about .phase__fold[open] summary::after {
  content: " －";
}

.page-about .phase__fold .fold-body ul {
  margin: 0.6rem 0 0;
  padding-left: 1.05rem;
  color: rgba(242, 246, 255, 0.82);
  line-height: 1.75;
}

.page-about .phase__fold .fold-body li + li {
  margin-top: 0.28rem;
}

.page-about .about-timeline__more {
  margin: 1.3rem 0 0;
  font-size: 0.84rem;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 数据读法 ---------- */
.page-about .about-notes {
  margin-top: 1.8rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.9rem;
}

.page-about .note-block {
  position: relative;
  background: linear-gradient(160deg, var(--blue-mid) 0%, var(--bg-2) 68%);
  border: 1px solid var(--line);
  border-radius: var(--about-radius);
  padding: 1.25rem 1.15rem 1.3rem;
  overflow: hidden;
}

.page-about .note-block::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 96px;
  height: 4px;
  background: linear-gradient(90deg, var(--cyan), var(--orange));
}

.page-about .note-block__idx {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--lime);
  margin: 0 0 0.55rem;
}

.page-about .note-block__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.12rem;
  color: var(--ink);
  margin: 0 0 0.65rem;
  letter-spacing: -0.01em;
}

.page-about .note-block p {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.85;
  color: rgba(242, 246, 255, 0.84);
}

.page-about .about-notes__hint {
  margin: 1.2rem 0 0;
  font-size: 0.84rem;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 联系 ---------- */
.page-about .about-talk {
  border-top: 1px solid var(--line);
  padding-top: clamp(2rem, 4vw, 3rem);
}

.page-about .talk-grid {
  margin-top: 1.7rem;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.85rem;
}

.page-about .talk-card {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-left: 3px solid var(--cyan);
  border-radius: 6px 16px 16px 6px;
  padding: 1rem 1.1rem 1.1rem;
}

.page-about .talk-card__label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.page-about .talk-card__value {
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--ink);
  word-break: break-word;
}

.page-about .talk-card__value.mono {
  font-family: var(--font-mono);
  letter-spacing: 0.01em;
  color: var(--cyan);
}

.page-about .talk-card__note {
  font-size: 0.78rem;
  line-height: 1.65;
  color: var(--muted);
}

.page-about .talk-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 1.5rem;
}

/* ---------- 断点 ---------- */
@media (min-width: 620px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 768px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  }

  .page-about .column-list li {
    grid-template-columns: 3.4rem minmax(0, 1fr);
    gap: 0.4rem 1.2rem;
    padding: 1.05rem 0.25rem 1.1rem;
  }

  .page-about .column-list__body {
    display: grid;
    grid-template-columns: 8.5rem minmax(0, 1fr);
    gap: 0.9rem;
    align-items: baseline;
  }

  .page-about .column-list__name {
    margin-bottom: 0;
  }

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

  .page-about .about-timeline::before {
    left: 0;
    right: 0;
    top: -0.9rem;
    bottom: auto;
    width: auto;
    height: 2px;
    background: linear-gradient(90deg, var(--cyan), var(--orange) 55%, var(--line));
  }

  .page-about .phase {
    padding: 1.6rem 1.15rem 1.15rem;
  }

  .page-about .phase::before {
    left: 1.15rem;
    top: -1.35rem;
  }
}

@media (min-width: 1024px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(2rem, 4vw, 4rem);
  }

  .page-about .about-rail {
    position: sticky;
    top: 2rem;
    align-self: start;
  }

  .page-about .about-rail .rail-list {
    flex-direction: column;
    overflow: visible;
    gap: 0.15rem;
    padding-bottom: 0;
  }

  .page-about .about-rail .rail-link {
    border: 0;
    border-left: 2px solid var(--line);
    border-radius: 0;
    background: transparent;
    padding: 0.5rem 0.7rem;
    font-size: 0.84rem;
  }

  .page-about .about-rail .rail-link:hover,
  .page-about .about-rail .rail-link:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(34, 230, 216, 0.07);
  }

  .page-about .crew-grid {
    grid-template-columns: 1.15fr 0.85fr 1fr 0.9fr;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.85fr);
  }

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

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

@media (prefers-reduced-motion: reduce) {
  .page-about .crew-card,
  .page-about .phase,
  .page-about .about-rail .rail-link,
  .page-about .crew-card__more {
    transition: opacity 0.2s linear;
  }

  .page-about .crew-card:hover,
  .page-about .phase:hover {
    transform: none;
  }
}