.page-about {
  --ab-rail-w: 232px;
  position: relative;
  isolation: isolate;
  color: var(--mist);
  padding-bottom: 24px;
}

.page-about .about-hero {
  position: relative;
  padding-top: 28px;
  padding-bottom: 44px;
  border-bottom: 1px solid var(--rule);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(42, 53, 64, 0.5) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(42, 53, 64, 0.5) 1px, transparent 1px);
  background-size: 64px 64px;
  -webkit-mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 82%);
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.9), transparent 82%);
}

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

.page-about .about-hero__lead .ob-h1 {
  margin: 12px 0 20px;
}

.page-about .about-hero__mark {
  color: var(--yellow);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .about-hero__side {
  background: var(--carbon);
  border: 1px solid var(--rule);
  border-top: 3px solid var(--yellow);
  border-radius: var(--radius);
  padding: 18px 20px 8px;
}

.page-about .about-hero__side-title {
  margin: 0 0 6px;
  font-size: var(--fs-xs);
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

.page-about .about-hero__facts {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-fact {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 4px 16px;
  padding: 12px 0;
  border-bottom: 1px dashed var(--rule);
}

.page-about .about-fact:last-child {
  border-bottom: 0;
}

.page-about .about-fact__v {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  color: var(--white);
  white-space: nowrap;
  line-height: 1.2;
}

.page-about .about-fact__k {
  font-size: var(--fs-sm);
  color: var(--text-mid);
  line-height: 1.5;
  text-align: right;
  flex: 1 1 140px;
}

/* ---------- 长卷结构：左侧版本栏 + 右侧主内容 ---------- */

.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 40px;
  padding-top: 44px;
  padding-bottom: 40px;
}

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

.page-about .about-rail__title {
  margin: 0 0 14px;
  font-size: var(--fs-xs);
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

.page-about .about-rail__list {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-rail__list::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(to bottom, var(--rule), rgba(42, 53, 64, 0.12));
}

.page-about .about-rail__item {
  position: relative;
  padding: 8px 0 10px 22px;
  cursor: default;
}

.page-about .about-rail__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 14px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--rule);
  transition: background-color var(--t-fast), border-color var(--t-fast);
}

.page-about .about-rail__item:hover::before,
.page-about .about-rail__item:focus-within::before,
.page-about .about-rail__item:focus::before {
  background: var(--yellow);
  border-color: var(--yellow);
}

.page-about .about-rail__year {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  letter-spacing: 0.04em;
  color: var(--text-dim);
  transition: color var(--t-fast);
}

.page-about .about-rail__label {
  display: block;
  margin-top: 2px;
  font-size: var(--fs-sm);
  font-weight: 600;
  color: var(--mist);
  transition: color var(--t-fast);
}

.page-about .about-rail__item:hover .about-rail__year,
.page-about .about-rail__item:focus-within .about-rail__year,
.page-about .about-rail__item:hover .about-rail__label,
.page-about .about-rail__item:focus-within .about-rail__label {
  color: var(--yellow);
}

.page-about .about-rail__desc {
  display: grid;
  grid-template-rows: 0fr;
  margin-top: 6px;
  opacity: 0;
  transition: grid-template-rows var(--t-fold), opacity var(--t-fold);
}

.page-about .about-rail__desc > p {
  overflow: hidden;
  margin: 0;
  font-size: var(--fs-xs);
  line-height: 1.7;
  color: var(--text-mid);
}

.page-about .about-rail__item:hover .about-rail__desc,
.page-about .about-rail__item:focus-within .about-rail__desc,
.page-about .about-rail__item:focus .about-rail__desc {
  grid-template-rows: 1fr;
  opacity: 1;
}

.page-about .about-flow {
  display: grid;
  gap: 48px;
  min-width: 0;
}

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

.page-about .about-block > .ob-h2 {
  margin: 8px 0 0;
}

.page-about .about-block > .ob-lede {
  margin-top: 14px;
}

.page-about .about-divider {
  position: relative;
  height: 22px;
}

.page-about .about-divider::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 1px;
  background: var(--rule);
  transform: rotate(-0.9deg);
  transform-origin: left center;
  transition: background var(--t-line), height var(--t-line);
}

.page-about .about-divider:hover::before {
  background: var(--yellow);
  height: 2px;
}

/* ---------- 图 ---------- */

.page-about .about-figure {
  margin: 24px 0 0;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--carbon);
  overflow: hidden;
}

.page-about .about-block__split .about-figure {
  margin-top: 0;
}

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

.page-about .about-figure--tall img {
  aspect-ratio: 4 / 5;
}

.page-about .about-figure--wide img {
  aspect-ratio: 3 / 2;
}

.page-about .about-cap {
  padding: 12px 16px;
  border-top: 1px solid var(--rule);
  font-size: var(--fs-xs);
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--text-dim);
}

.page-about .about-block__split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
  margin-top: 22px;
}

.page-about .about-block__body .ob-text + .ob-text {
  margin-top: 14px;
}

/* ---------- 团队名单 ---------- */

.page-about .about-roster {
  display: grid;
  gap: 0;
  margin: 26px 0 0;
}

.page-about .about-roster__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 6px 16px;
  padding: 16px 0;
  border-bottom: 1px solid var(--rule);
}

.page-about .about-roster__row:first-child {
  border-top: 1px solid var(--rule);
}

.page-about .about-roster__role {
  margin: 0;
  font-size: var(--fs-body);
  font-weight: 700;
  color: var(--white);
}

.page-about .about-roster__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-body);
  font-weight: 700;
  color: var(--yellow);
  white-space: nowrap;
  text-align: right;
}

.page-about .about-roster__desc {
  grid-column: 1 / -1;
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.7;
  color: var(--text-mid);
}

/* ---------- 90 秒流程 ---------- */

.page-about .about-steps {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .about-step {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 6px 16px;
  padding: 18px 0;
  border-top: 1px solid var(--rule);
  transition: border-color var(--t-fast);
}

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

.page-about .about-step:hover {
  border-top-color: var(--yellow);
}

.page-about .about-step__no {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  line-height: 1.15;
  color: var(--yellow);
}

.page-about .about-step__title {
  display: block;
  font-size: var(--fs-body);
  font-weight: 700;
  color: var(--white);
  margin-bottom: 4px;
}

.page-about .about-step__text {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.75;
  color: var(--text-mid);
}

/* ---------- 每周三 ---------- */

.page-about .about-weekly {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
  margin-top: 22px;
}

.page-about .about-weekly__main .ob-text + .ob-text {
  margin-top: 14px;
}

.page-about .about-weekly__facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-weekly__fact {
  background: var(--carbon);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--green);
  border-radius: var(--radius);
  padding: 14px 16px;
  transition: background-color var(--t-fast);
}

.page-about .about-weekly__fact:hover {
  background: var(--navy);
}

.page-about .about-weekly__fact-v {
  display: block;
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  color: var(--white);
  line-height: 1.2;
}

.page-about .about-weekly__fact-k {
  display: block;
  margin-top: 4px;
  font-size: var(--fs-sm);
  color: var(--text-mid);
}

/* ---------- 三道关 ---------- */

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

.page-about .about-criterion {
  background: var(--carbon);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--rule);
  border-radius: var(--radius);
  padding: 20px;
  transition: background-color var(--t-fast), border-left-color var(--t-fast);
}

.page-about .about-criterion:hover {
  background: var(--navy);
  border-left-color: var(--yellow);
}

.page-about .about-criterion__no {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  letter-spacing: 0.08em;
  color: var(--text-dim);
  margin-bottom: 8px;
}

.page-about .about-criterion__title {
  margin: 0 0 10px;
  font-size: var(--fs-h4);
  line-height: 1.25;
  color: var(--white);
}

.page-about .about-criterion__text {
  margin: 0;
  font-size: var(--fs-sm);
  line-height: 1.75;
  color: var(--text-mid);
}

/* ---------- 为谁而做 ---------- */

.page-about .about-audience {
  display: grid;
  gap: 0;
  margin-top: 26px;
}

.page-about .about-audience__item {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 6px 16px;
  padding: 22px 0;
  border-top: 1px solid var(--rule);
  transition: padding-left var(--t-fast), border-color var(--t-fast);
}

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

.page-about .about-audience__item:hover {
  padding-left: 10px;
  border-top-color: var(--yellow);
}

.page-about .about-audience__no {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  line-height: 1.15;
  color: var(--yellow);
}

.page-about .about-audience__body .ob-h3 {
  margin: 0 0 8px;
}

.page-about .about-audience__body .ob-text {
  margin: 0;
}

/* ---------- 接着看 ---------- */

.page-about .about-next {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  border-top: 1px solid var(--rule);
}

.page-about .about-next__item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 16px;
  padding: 16px 0;
  border-bottom: 1px solid var(--rule);
}

.page-about .about-next__label {
  min-width: 96px;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-next__text {
  flex: 1 1 260px;
  font-size: var(--fs-sm);
  line-height: 1.7;
  color: var(--text-mid);
}

/* ---------- 断点 ---------- */

@media (min-width: 720px) {
  .page-about .about-block__split {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .about-roster__row {
    grid-template-columns: 200px 96px minmax(0, 1fr);
    align-items: baseline;
  }

  .page-about .about-roster__desc {
    grid-column: auto;
  }

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

  .page-about .about-weekly {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 32px;
    align-items: start;
  }
}

@media (min-width: 1000px) {
  .page-about .about-hero {
    padding-top: 44px;
    padding-bottom: 64px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 64px;
    align-items: end;
  }

  .page-about .about-layout {
    grid-template-columns: var(--ab-rail-w) minmax(0, 1fr);
    gap: 72px;
    align-items: start;
    padding-top: 56px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 128px;
    border-left: 1px solid var(--rule);
    padding-left: 20px;
  }

  .page-about .about-flow {
    gap: 64px;
  }

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

  .page-about .about-criterion:nth-child(1) {
    grid-column: span 7;
  }

  .page-about .about-criterion:nth-child(2) {
    grid-column: span 5;
  }

  .page-about .about-criterion:nth-child(3) {
    grid-column: 4 / span 9;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__item::before,
  .page-about .about-rail__desc,
  .page-about .about-rail__year,
  .page-about .about-rail__label,
  .page-about .about-criterion,
  .page-about .about-weekly__fact,
  .page-about .about-audience__item,
  .page-about .about-step,
  .page-about .about-divider::before {
    transition: none;
  }

  .page-about .about-divider::before {
    transform: none;
  }
}