.page-about {
  --about-rail: 148px;
  background: var(--ink-900);
  color: var(--ice);
  padding-bottom: clamp(1.5rem, 5vw, 3rem);
}

.page-about .breadcrumb {
  padding-top: clamp(.9rem, 2.5vw, 1.5rem);
}

.page-about a:focus-visible,
.page-about [tabindex="0"]:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  padding: clamp(1rem, 3vw, 2rem) 0 clamp(2rem, 5vw, 3.5rem);
}

.page-about .about-hero__frame {
  position: relative;
  overflow: hidden;
  padding: clamp(1.15rem, 3.5vw, 2.75rem);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background:
    radial-gradient(120% 90% at 100% 0%, rgba(53, 242, 208, .14), transparent 62%),
    linear-gradient(180deg, var(--ink-800), var(--ink-900));
  box-shadow: var(--shadow-raise);
}

.page-about .about-hero__frame::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 12px;
  background: repeating-linear-gradient(90deg, var(--line-strong) 0 1px, transparent 1px 16px);
  opacity: .75;
  pointer-events: none;
}

.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  right: -60px;
  bottom: -80px;
  width: 240px;
  height: 240px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 107, 44, .18), transparent 70%);
  pointer-events: none;
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.25rem, 3vw, 2.5rem);
  align-items: start;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.95rem, 6vw, 3.5rem);
  line-height: 1.08;
  letter-spacing: -.015em;
  margin: .45rem 0 0;
  color: var(--ice);
  text-wrap: balance;
}

.page-about .about-hero__lead {
  margin: clamp(.85rem, 2vw, 1.15rem) 0 0;
  max-width: 48ch;
  font-size: clamp(.93rem, 1.6vw, 1.05rem);
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-metrics {
  list-style: none;
  margin: clamp(1.2rem, 3vw, 1.9rem) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: .85rem .7rem;
}

.page-about .about-metrics li {
  padding-left: .7rem;
  border-left: 2px solid var(--cyan-deep);
}

.page-about .about-metrics__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.25rem, 3vw, 1.85rem);
  font-weight: 600;
  letter-spacing: -.03em;
  color: var(--cyan);
}

.page-about .about-metrics__label {
  display: block;
  margin-top: .2rem;
  font-size: .76rem;
  line-height: 1.4;
  color: var(--mist);
}

/* ---------- 图片框 ---------- */
.page-about .about-figure {
  margin: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: var(--ink-700);
}

.page-about .about-figure__media {
  position: relative;
  overflow: hidden;
}

.page-about .about-figure--portrait .about-figure__media { aspect-ratio: 5 / 7; }
.page-about .about-figure--wide .about-figure__media { aspect-ratio: 7 / 4; }
.page-about .about-figure--banner .about-figure__media { aspect-ratio: 16 / 7; }

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

.page-about .about-figure figcaption {
  padding: .55rem .8rem;
  font-size: .75rem;
  line-height: 1.5;
  color: var(--mist);
  background: rgba(6, 26, 21, .92);
  border-top: 1px solid var(--line);
}

/* ---------- 长卷章节与左侧刻度 ---------- */
.page-about .about-chapter {
  border-top: 1px solid var(--line);
}

.page-about .about-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1rem, 3vw, 2.5rem);
}

.page-about .about-rail {
  display: flex;
  align-items: baseline;
  gap: .6rem;
}

.page-about .about-rail__num {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 600;
  letter-spacing: -.04em;
  color: var(--cyan);
}

.page-about .about-rail__label {
  font-size: .76rem;
  letter-spacing: .18em;
  color: var(--mist);
}

.page-about .about-body > * + * {
  margin-top: clamp(1rem, 2.4vw, 1.6rem);
}

.page-about .about-body p {
  color: var(--mist);
  line-height: 1.8;
}

/* ---------- 起点要点 ---------- */
.page-about .about-points {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: .55rem;
}

.page-about .about-points li {
  display: grid;
  grid-template-columns: 8px minmax(0, 1fr);
  gap: .7rem;
  align-items: start;
  padding: .72rem .85rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: rgba(215, 255, 244, .035);
  font-size: .9rem;
  line-height: 1.7;
  color: var(--ice);
}

.page-about .about-points li::before {
  content: "";
  width: 8px;
  height: 8px;
  margin-top: .5rem;
  border-radius: 2px;
  background: var(--orange);
}

/* ---------- 版本时间线 ---------- */
.page-about .version-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .version {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: .2rem .95rem;
  padding: clamp(.9rem, 2vw, 1.2rem) .9rem clamp(.9rem, 2vw, 1.2rem) 1.1rem;
  border-bottom: 1px solid var(--line);
  transition: background var(--t) var(--ease);
}

.page-about .version::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--orange);
  transform: scaleY(.18);
  transform-origin: top;
  transition: transform var(--t) var(--ease);
}

.page-about .version:hover,
.page-about .version:focus-within {
  background: rgba(255, 107, 44, .07);
}

.page-about .version:hover::before,
.page-about .version:focus-within::before {
  transform: scaleY(1);
}

.page-about .version__year {
  font-family: var(--font-mono);
  font-size: clamp(1.1rem, 2.4vw, 1.45rem);
  font-weight: 600;
  letter-spacing: -.03em;
  color: var(--orange);
}

.page-about .version__title {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5rem;
  margin: 0;
  font-size: clamp(1rem, 2vw, 1.15rem);
  font-weight: 700;
  color: var(--ice);
}

.page-about .version__text {
  margin: .4rem 0 0;
  font-size: .9rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 团队四列 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: .7rem;
}

.page-about .team-cell {
  display: flex;
  flex-direction: column;
  gap: .45rem;
  padding: .95rem .9rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: rgba(215, 255, 244, .04);
  transition: transform var(--t) var(--ease), border-color var(--t) var(--ease), background var(--t) var(--ease);
}

.page-about .team-cell:hover,
.page-about .team-cell:focus-visible {
  transform: translateY(-3px);
  border-color: var(--cyan);
  background: rgba(53, 242, 208, .07);
}

.page-about .team-cell__idx {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--yellow);
}

.page-about .team-cell .card__title {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
  color: var(--ice);
}

.page-about .team-cell__text {
  margin: 0;
  font-size: .84rem;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 流程条 ---------- */
.page-about .about-flow {
  display: flex;
  flex-direction: column;
  gap: .4rem;
}

.page-about .flow-step {
  padding: .9rem .85rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: linear-gradient(160deg, rgba(11, 143, 126, .16), rgba(11, 143, 126, .04));
}

.page-about .flow-step__dot {
  display: block;
  width: 10px;
  height: 10px;
  margin-bottom: .6rem;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(53, 242, 208, .16);
}

.page-about .flow-step__title {
  margin: 0;
  font-size: .95rem;
  font-weight: 700;
  color: var(--ice);
}

.page-about .flow-step__text {
  margin: .35rem 0 0;
  font-size: .82rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .flow-arrow {
  align-self: center;
  flex: 0 0 auto;
  width: 18px;
  height: 18px;
  color: var(--orange);
  transform: rotate(90deg);
}

/* ---------- 社群与覆盖 ---------- */
.page-about .about-community {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1rem, 3vw, 2rem);
}

.page-about .about-community__panel {
  position: relative;
}

.page-about .constellation {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: .45rem;
}

.page-about .constellation li {
  position: relative;
}

.page-about .constellation .dot {
  display: block;
  height: 34px;
  border-radius: 9px;
  border: 1px solid var(--line-strong);
  background: linear-gradient(150deg, rgba(53, 242, 208, .18), rgba(11, 143, 126, .06));
  transition: background var(--t) var(--ease), border-color var(--t) var(--ease);
}

.page-about .constellation li:hover .dot,
.page-about .constellation li:focus-visible .dot {
  background: var(--cyan);
  border-color: var(--cyan);
}

.page-about .dot__tip {
  position: absolute;
  left: 50%;
  bottom: calc(100% + 6px);
  z-index: 3;
  padding: .2rem .45rem;
  font-size: .7rem;
  line-height: 1.4;
  white-space: nowrap;
  color: var(--ice);
  background: var(--ink-700);
  border: 1px solid var(--line-strong);
  border-radius: 6px;
  opacity: 0;
  transform: translateX(-50%) translateY(4px);
  pointer-events: none;
  transition: opacity var(--t) var(--ease), transform var(--t) var(--ease);
}

.page-about .constellation li:hover .dot__tip,
.page-about .constellation li:focus-visible .dot__tip {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.page-about .about-community__hint {
  margin: .7rem 0 0;
  font-size: .76rem;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .about-coverage {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: .9rem .8rem;
  align-content: start;
}

.page-about .about-coverage > div {
  padding-left: .75rem;
  border-left: 2px solid var(--yellow);
}

.page-about .about-coverage dt {
  font-family: var(--font-mono);
  font-size: clamp(1.15rem, 2.6vw, 1.55rem);
  font-weight: 600;
  letter-spacing: -.03em;
  color: var(--yellow);
}

.page-about .about-coverage dd {
  margin: .2rem 0 0;
  font-size: .78rem;
  line-height: 1.5;
  color: var(--mist);
}

/* ---------- 收尾 ---------- */
.page-about .about-next__inner {
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
  padding: clamp(1.2rem, 4vw, 2.5rem);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background: linear-gradient(120deg, rgba(53, 242, 208, .12), rgba(255, 107, 44, .09));
}

.page-about .about-next__copy p {
  margin: .6rem 0 0;
  max-width: 54ch;
  font-size: .92rem;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-next__actions {
  display: flex;
  flex-wrap: wrap;
  gap: .6rem;
}

/* ---------- 媒体查询 ---------- */
@media (min-width: 560px) {
  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .constellation {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
}

@media (min-width: 720px) {
  .page-about .version {
    grid-template-columns: 92px minmax(0, 1fr);
    align-items: start;
  }
}

@media (min-width: 880px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .65fr);
  }

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

  .page-about .about-community {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
  }
}

@media (min-width: 940px) {
  .page-about .about-row {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
  }

  .page-about .about-rail {
    position: sticky;
    top: 5.5rem;
    align-self: start;
    flex-direction: column;
    align-items: flex-start;
    gap: .35rem;
    padding-left: 1rem;
    border-left: 1px solid var(--line);
  }

  .page-about .about-rail__num {
    font-size: 2.3rem;
  }

  .page-about .about-flow {
    flex-direction: row;
    align-items: stretch;
  }

  .page-about .flow-step {
    flex: 1 1 0;
    min-width: 0;
  }

  .page-about .flow-arrow {
    transform: none;
  }

  .page-about .about-next__inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }

  .page-about .about-next__actions {
    flex: 0 0 auto;
  }
}

@media (min-width: 1024px) {
  .page-about .team-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .team-cell,
  .page-about .version,
  .page-about .version::before,
  .page-about .dot__tip {
    transition: none;
  }

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