.page-about {
  --about-surface: #FFFFFF;
  --about-rail-w: 96px;
  --about-coop-line: rgba(244, 246, 244, 0.18);
  background: var(--paper);
  overflow-x: clip;
  padding-bottom: 56px;
}

.page-about .about-layout {
  display: grid;
  gap: 26px;
  margin-top: 18px;
}

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

/* ---------- 左侧刻度栏 ---------- */
.page-about .about-rail {
  min-width: 0;
}

.page-about .about-rail__inner {
  display: flex;
  align-items: center;
  gap: 10px;
  overflow-x: auto;
  padding: 2px 0 8px;
}

.page-about .about-rail__label {
  margin: 0;
  flex: none;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--slate);
  white-space: nowrap;
}

.page-about .about-rail__list,
.page-about .about-rail__scale {
  list-style: none;
  margin: 0;
  padding: 0;
}

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

.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 6px;
  padding: 6px 10px;
  border: 1px solid var(--line);
  background: var(--about-surface);
  color: var(--ink-700);
  text-decoration: none;
  font-size: var(--fs-12);
  white-space: nowrap;
  transition: border-color 0.18s ease, color 0.18s ease, background-color 0.18s ease;
}

.page-about .about-rail__no {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--signal-500);
}

.page-about .about-rail__link:hover {
  border-color: var(--ink-500);
  color: var(--ink-900);
}

.page-about .about-rail__link:focus-visible,
.page-about .about-rail__scale-link:focus-visible {
  outline: 2px solid var(--signal-500);
  outline-offset: 2px;
}

.page-about .about-rail__link[aria-current="true"],
.page-about .about-rail__link[aria-current="page"] {
  background: var(--signal-100);
  border-color: var(--signal-500);
  color: var(--ink-900);
}

.page-about .about-rail__scale-wrap {
  display: none;
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  position: relative;
  border: 1px solid var(--line);
  background: var(--about-surface);
  background-image:
    repeating-linear-gradient(0deg, transparent 0 31px, rgba(20, 32, 29, 0.045) 31px 32px),
    repeating-linear-gradient(90deg, transparent 0 31px, rgba(20, 32, 29, 0.045) 31px 32px);
  padding: 22px 16px 24px;
}

.page-about .about-hero::before,
.page-about .about-hero::after {
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border-style: solid;
  border-color: var(--signal-500);
}

.page-about .about-hero::before {
  top: -1px;
  left: -1px;
  border-width: 2px 0 0 2px;
}

.page-about .about-hero::after {
  right: -1px;
  bottom: -1px;
  border-width: 0 2px 2px 0;
}

.page-about .about-hero__grid {
  display: grid;
  gap: 22px;
}

.page-about .about-hero__kicker {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--signal-500);
}

.page-about .about-hero h1 {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--fs-32);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--ink-900);
}

.page-about .about-hero__lead {
  margin: 14px 0 0;
  max-width: 36em;
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--slate);
}

.page-about .about-hero__stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 16px;
  margin: 22px 0 0;
  padding: 16px 0 0;
  border-top: 1px solid var(--line);
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--fs-20);
  color: var(--ink-700);
  letter-spacing: 0.02em;
}

.page-about .about-stat__label {
  display: block;
  margin-top: 2px;
  font-size: var(--fs-12);
  color: var(--slate);
}

.page-about .about-hero__media {
  margin: 0;
  background: var(--paper);
}

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

.page-about .media-frame__caption {
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--slate);
}

/* ---------- 区块通用 ---------- */
.page-about .about-section {
  margin-top: 44px;
}

.page-about .about-section .section-head {
  margin-bottom: 16px;
}

.page-about .about-section__lede {
  margin: 0 0 18px;
  max-width: 40em;
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--black);
}

.page-about .about-section__lede + .about-section__lede {
  margin-top: -4px;
}

/* ---------- 团队三栏 ---------- */
.page-about .about-team {
  display: grid;
  gap: 16px;
}

.page-about .about-team__card {
  background: var(--about-surface);
  border: 1px solid var(--line);
  border-top: 2px solid var(--ink-700);
  padding: 18px 16px;
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.page-about .about-team__card:focus-visible {
  outline: 2px solid var(--signal-500);
  outline-offset: 3px;
}

.page-about .about-team__no {
  margin: 0;
  font-size: var(--fs-12);
  color: var(--signal-500);
  letter-spacing: 0.08em;
}

.page-about .about-team__name {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-size: var(--fs-20);
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .about-team__count {
  margin: 2px 0 0;
  font-size: var(--fs-12);
  color: var(--slate);
}

.page-about .about-team__desc {
  margin: 10px 0 0;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--black);
}

.page-about .about-team__label {
  margin: 14px 0 0;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--slate);
}

.page-about .about-team__outputs {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 8px 0 0;
  padding: 0;
}

.page-about .about-team__outputs li {
  padding: 3px 8px;
  background: var(--signal-100);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.02em;
}

/* ---------- 流程 ---------- */
.page-about .about-process {
  display: grid;
  gap: 24px;
  align-items: start;
}

.page-about .about-steps {
  list-style: none;
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
}

.page-about .about-step {
  position: relative;
  border-top: 2px solid var(--ink-700);
  padding-top: 10px;
}

.page-about .about-step__no {
  margin: 0;
  font-size: var(--fs-12);
  color: var(--signal-500);
  letter-spacing: 0.08em;
}

.page-about .about-step__title {
  margin: 4px 0 0;
  font-family: var(--font-display);
  font-size: var(--fs-16);
  color: var(--ink-900);
}

.page-about .about-step__text {
  margin: 6px 0 0;
  font-size: var(--fs-14);
  line-height: 1.7;
  color: var(--slate);
}

.page-about .about-process__media {
  margin: 0;
  order: -1;
  max-width: 320px;
  background: var(--paper);
}

/* ---------- 批次时间线 ---------- */
.page-about .about-batches {
  display: grid;
  gap: 16px;
  margin-top: 22px;
}

.page-about .about-batch {
  background: var(--about-surface);
  border: 1px solid var(--line);
  padding: 16px 16px 18px;
  min-width: 0;
}

.page-about .about-batch--current {
  border-color: var(--signal-500);
  box-shadow: inset 3px 0 0 var(--signal-500);
}

.page-about .about-batch__head {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.page-about .about-batch__state {
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--signal-500);
}

.page-about .about-batch__title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-size: var(--fs-20);
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .about-batch__text {
  margin: 8px 0 0;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--slate);
}

.page-about .about-batch__link {
  display: inline-block;
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  color: var(--ink-500);
  text-decoration: none;
  border-bottom: 1px solid var(--signal-500);
}

.page-about .about-batch__link:hover {
  color: var(--signal-500);
}

.page-about .about-batches__figure {
  margin: 4px 0;
}

.page-about .about-batches__figure .media-frame {
  margin: 0;
}

.page-about .about-batches__figure img {
  aspect-ratio: 10 / 7;
  object-fit: cover;
}

/* ---------- 选题标准 ---------- */
.page-about .about-panel {
  background: var(--about-surface);
  border: 1px solid var(--line);
  padding: 20px 16px 22px;
}

.page-about .about-panel__lede {
  margin: 0;
  max-width: 40em;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--slate);
}

.page-about .about-standard {
  display: grid;
  gap: 22px;
  margin-top: 20px;
}

.page-about .about-standard__label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--ink-500);
}

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

.page-about .about-list li {
  position: relative;
  padding-left: 16px;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--black);
}

.page-about .about-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.7em;
  width: 6px;
  height: 6px;
  background: var(--signal-500);
  transform: rotate(45deg);
}

.page-about .about-quote {
  margin: 22px 0 0;
  padding: 14px 16px;
  border-left: 3px solid var(--ink-700);
  background: var(--paper);
  font-family: var(--font-serif);
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--ink-900);
}

/* ---------- 合作深色面板 ---------- */
.page-about .about-coop {
  position: relative;
  overflow: hidden;
  margin-top: 18px;
  padding: 22px 16px 24px;
  background: var(--ink-900);
  color: var(--paper);
  border-radius: 2px;
}

.page-about .about-coop::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(244, 246, 244, 0.06) 0 1px,
    transparent 1px 46px
  );
}

.page-about .about-coop > * {
  position: relative;
  z-index: 1;
}

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

.page-about .about-coop__item {
  display: grid;
  gap: 4px;
  padding: 16px 0;
  border-top: 1px solid var(--about-coop-line);
}

.page-about .about-coop__item:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-coop__no {
  font-size: var(--fs-12);
  letter-spacing: 0.1em;
  color: var(--signal-500);
}

.page-about .about-coop__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--fs-20);
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-coop__text {
  margin: 6px 0 0;
  max-width: 42em;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: rgba(244, 246, 244, 0.82);
}

.page-about .about-link {
  color: var(--signal-100);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-link:hover {
  color: var(--signal-500);
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

/* ---------- 加入与联系 ---------- */
.page-about .about-join {
  display: grid;
  gap: 22px;
  align-items: start;
}

.page-about .about-contact {
  background: var(--about-surface);
  border: 1px solid var(--line);
  border-top: 2px solid var(--signal-500);
  padding: 18px 16px;
}

.page-about .about-contact__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--ink-500);
}

.page-about .about-contact__list {
  margin: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-contact__row {
  display: grid;
  gap: 2px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--line);
}

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

.page-about .about-contact__row dt {
  font-size: var(--fs-12);
  color: var(--slate);
}

.page-about .about-contact__row dd {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.65;
  color: var(--ink-900);
  overflow-wrap: anywhere;
}

.page-about .about-contact__row dd.mono {
  font-family: var(--font-mono);
  letter-spacing: 0.03em;
}

.page-about .about-contact__note {
  margin: 14px 0 0;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: var(--fs-12);
  line-height: 1.7;
  color: var(--slate);
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero {
    padding: 28px 24px 30px;
  }

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

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

  .page-about .about-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .about-process__media {
    order: 0;
    max-width: none;
  }

  .page-about .about-standard {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px;
  }

  .page-about .about-coop__item {
    grid-template-columns: 44px minmax(0, 1fr);
    column-gap: 16px;
  }

  .page-about .about-join {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 28px;
  }
}

@media (min-width: 920px) {
  .page-about {
    padding-bottom: 72px;
  }

  .page-about .about-layout {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: 40px;
    align-items: start;
    margin-top: 24px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 24px;
  }

  .page-about .about-rail__inner {
    flex-direction: column;
    align-items: stretch;
    gap: 14px;
    overflow: visible;
    padding: 0;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0;
  }

  .page-about .about-rail__link {
    border: 0;
    border-left: 2px solid var(--line);
    background: transparent;
    padding: 7px 0 7px 8px;
    white-space: normal;
    line-height: 1.3;
  }

  .page-about .about-rail__no {
    display: block;
    margin-bottom: 2px;
  }

  .page-about .about-rail__link:hover {
    border-left-color: var(--ink-500);
  }

  .page-about .about-rail__link[aria-current="true"],
  .page-about .about-rail__link[aria-current="page"] {
    background: transparent;
    border-left-color: var(--signal-500);
    color: var(--ink-900);
  }

  .page-about .about-rail__scale-wrap {
    display: block;
    border-top: 1px dashed var(--line);
    padding-top: 10px;
  }

  .page-about .about-rail__scale {
    display: flex;
    flex-direction: column;
    gap: 2px;
    margin-top: 6px;
  }

  .page-about .about-rail__scale-link {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 2px 0;
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--slate);
    text-decoration: none;
    transition: color 0.12s ease;
  }

  .page-about .about-rail__scale-link::before {
    content: "";
    width: 8px;
    height: 1px;
    background: var(--line);
    transition: width 0.12s ease, background-color 0.12s ease;
  }

  .page-about .about-rail__scale-link:hover {
    color: var(--ink-700);
  }

  .page-about .about-rail__scale-link[aria-current="true"] {
    color: var(--signal-500);
  }

  .page-about .about-rail__scale-link[aria-current="true"]::before {
    width: 16px;
    background: var(--signal-500);
  }

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

  .page-about .about-hero h1 {
    font-size: var(--fs-44);
  }

  .page-about .about-section {
    margin-top: 64px;
  }

  .page-about .about-section .section-head {
    margin-bottom: 20px;
  }

  .page-about .about-team {
    gap: 20px;
  }

  .page-about .about-team__card {
    padding: 20px 18px;
  }

  .page-about .about-team__label {
    margin-top: 16px;
  }

  .page-about .about-team__outputs {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.2s ease, opacity 0.2s ease;
  }

  .page-about .about-team__card:hover,
  .page-about .about-team__card:focus-within {
    border-top-color: var(--signal-500);
    transform: translateY(-2px);
  }

  .page-about .about-team__card:hover .about-team__outputs,
  .page-about .about-team__card:focus-within .about-team__outputs {
    max-height: 90px;
    opacity: 1;
  }

  .page-about .about-process {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 34px;
  }

  .page-about .about-steps {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0;
  }

  .page-about .about-step {
    padding: 10px 12px 0 0;
  }

  .page-about .about-step:not(:last-child)::after {
    content: "›";
    position: absolute;
    top: 4px;
    right: 2px;
    font-family: var(--font-mono);
    font-size: var(--fs-20);
    line-height: 1;
    color: var(--line);
  }

  .page-about .about-batches {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 20px 24px;
  }

  .page-about .about-batch--a {
    grid-column: 1 / span 9;
  }

  .page-about .about-batch--b {
    grid-column: 4 / span 8;
  }

  .page-about .about-batches__figure {
    grid-column: 3 / span 8;
    margin: 6px 0 10px;
  }

  .page-about .about-panel {
    padding: 26px 28px 28px;
  }

  .page-about .about-coop {
    padding: 28px 32px 30px;
  }

  .page-about .about-contact {
    padding: 20px 20px 22px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-team__card,
  .page-about .about-team__outputs,
  .page-about .about-rail__link,
  .page-about .about-rail__scale-link,
  .page-about .about-rail__scale-link::before {
    transition: none;
  }
}