.page-about {
  --about-cut: 16px;
  --about-gap: clamp(18px, 2.6vw, 30px);
  --about-rule: rgba(42, 74, 63, 0.18);
  background: var(--paper-100);
  color: var(--ink-900);
  font-family: var(--font-body);
  padding-bottom: clamp(48px, 7vw, 88px);
  overflow-x: hidden;
}

.page-about .about-frame {
  max-width: var(--frame-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.page-about .about-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 18px 0 0;
  font-size: 12px;
  letter-spacing: 0.06em;
}

.page-about .about-breadcrumb-here {
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.page-about .about-hero {
  padding: clamp(20px, 3.4vw, 36px) 0 clamp(22px, 3.4vw, 38px);
  border-bottom: 1px solid var(--line);
}

.page-about .about-hero-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(29px, 5vw, 56px);
  line-height: 1.06;
  letter-spacing: -0.015em;
  margin: 10px 0 0;
  color: var(--ink-950);
  max-width: 19em;
}

.page-about .about-hero-lede {
  margin: 16px 0 0;
  max-width: 44em;
  font-size: 1.0625rem;
  line-height: 1.78;
  color: var(--text-muted);
}

.page-about .about-hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 20px;
}

.page-about .about-chip {
  display: inline-block;
  padding: 5px 11px;
  border: 1px solid var(--line);
  color: var(--green-700);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  background: var(--paper-200);
  clip-path: polygon(0 0, calc(100% - 8px) 0, 100% 8px, 100% 100%, 0 100%);
}

.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 48px);
  padding-top: clamp(26px, 4vw, 46px);
}

.page-about .about-rail-inner {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.page-about .about-rail-heading {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.page-about .about-rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2px;
  border-left: 1px solid var(--line);
}

.page-about .about-rail-link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 10px 9px 14px;
  color: var(--green-700);
  text-decoration: none;
  font-size: 0.9375rem;
  line-height: 1.4;
  border-left: 2px solid transparent;
  margin-left: -1px;
  transition: color var(--dur) ease, border-color var(--dur) ease, background-color var(--dur) ease;
}

.page-about .about-rail-num {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--text-muted);
}

.page-about .about-rail-link:hover,
.page-about .about-rail-link:focus-visible {
  color: var(--ink-950);
  border-left-color: var(--cyan-400);
  background: rgba(47, 243, 208, 0.1);
  outline: none;
}

.page-about .about-rail-link:focus-visible {
  box-shadow: inset 0 0 0 2px var(--cyan-400);
}

.page-about .about-rail-link[aria-current="true"] {
  color: var(--ink-950);
  border-left-color: var(--amber-400);
  background: var(--paper-200);
}

.page-about .about-rail-link[aria-current="true"] .about-rail-num {
  color: var(--amber-600);
}

.page-about .about-rail-top {
  align-self: flex-start;
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  padding-bottom: 2px;
}

.page-about .about-rail-top:hover,
.page-about .about-rail-top:focus-visible {
  color: var(--ink-950);
  border-bottom-color: var(--cyan-400);
  outline: none;
}

.page-about .about-flow {
  display: flex;
  flex-direction: column;
  gap: clamp(34px, 5vw, 66px);
  min-width: 0;
}

.page-about .about-section {
  scroll-margin-top: 24px;
  min-width: 0;
}

.page-about .about-section-head {
  max-width: 46em;
}

.page-about .about-section-index {
  margin: 0 0 8px;
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--amber-600);
}

.page-about .about-section-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 3.2vw, 36px);
  line-height: 1.14;
  letter-spacing: -0.01em;
  margin: 0;
  color: var(--ink-950);
}

.page-about .about-section-lede {
  margin: 12px 0 0;
  font-size: 1rem;
  line-height: 1.76;
  color: var(--text-muted);
}

.page-about .about-section--band {
  padding: clamp(22px, 3.4vw, 38px) clamp(16px, 3vw, 34px);
  background: var(--ink-950);
  clip-path: polygon(0 0, calc(100% - 22px) 0, 100% 22px, 100% 100%, 0 100%);
}

.page-about .about-section--band .about-section-title {
  color: var(--paper-100);
}

.page-about .about-section--band .about-section-lede {
  color: var(--muted-dark);
}

.page-about .about-section--band .about-section-index {
  color: var(--cyan-400);
}

.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--amber-600);
}

/* 图片容器 */
.page-about .about-media {
  position: relative;
  margin: 0;
  overflow: hidden;
  background: var(--ink-950);
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 0 100%);
}

.page-about .about-media--hero {
  margin-top: var(--about-gap);
}

.page-about .about-media--wide {
  margin-top: 22px;
  margin-bottom: 22px;
}

.page-about .about-media--team {
  margin-top: 22px;
  margin-bottom: var(--about-gap);
}

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

.page-about .about-media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(6, 19, 15, 0) 40%, rgba(6, 19, 15, 0.86) 100%);
  pointer-events: none;
}

.page-about .about-media-label {
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: 14px;
  z-index: 1;
  color: var(--cyan-200);
  font-size: 11px;
  letter-spacing: 0.13em;
  line-height: 1.5;
}

/* 摘要卡 */
.page-about .about-summary {
  list-style: none;
  margin: var(--about-gap) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .about-card {
  background: var(--ink-900);
  color: var(--paper-100);
  padding: 18px 18px 20px;
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, 0 100%);
  transition: transform var(--dur) ease, box-shadow var(--dur) ease;
}

.page-about .about-card:hover {
  transform: translateY(-2px);
  box-shadow: inset 0 0 0 2px var(--cyan-400);
}

.page-about .about-card-kicker {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan-400);
}

.page-about .about-card-title {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.0625rem;
  line-height: 1.32;
  letter-spacing: 0;
  color: var(--paper-100);
}

.page-about .about-card-text {
  margin: 8px 0 0;
  font-size: 0.875rem;
  line-height: 1.72;
  color: var(--muted-dark);
}

/* 时间线 */
.page-about .about-timeline {
  list-style: none;
  margin: 26px 0 0;
  padding: 0 0 0 18px;
  border-left: 1px solid var(--line);
}

.page-about .about-tl {
  position: relative;
  padding: 0 0 24px 16px;
}

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

.page-about .about-tl::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 9px;
  width: 15px;
  height: 2px;
  background: var(--cyan-400);
}

.page-about .about-tl-stage {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--amber-600);
}

.page-about .about-tl-title {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  line-height: 1.3;
  color: var(--ink-950);
}

.page-about .about-tl-text {
  margin: 7px 0 0;
  font-size: 0.9375rem;
  line-height: 1.76;
  color: var(--text-muted);
  max-width: 42em;
}

/* 生产流程 */
.page-about .about-process {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-step {
  background: var(--green-700);
  padding: 18px 18px 20px;
  border-top: 2px solid var(--cyan-400);
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 0 100%);
}

.page-about .about-step-num {
  margin: 0;
  font-size: 22px;
  line-height: 1;
  color: var(--amber-400);
  letter-spacing: 0.04em;
}

.page-about .about-step-title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.0625rem;
  color: var(--paper-100);
}

.page-about .about-step-text {
  margin: 7px 0 0;
  font-size: 0.875rem;
  line-height: 1.72;
  color: var(--muted-dark);
}

/* 版本谱系 */
.page-about .about-lineage {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.page-about .about-lineage-item {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 12px 12px 14px;
  border: 1px solid var(--line);
  background: var(--paper-100);
}

.page-about .about-lineage-bar {
  display: block;
  height: 4px;
  width: 100%;
  background: currentColor;
}

.page-about .about-lineage-item.is-legacy {
  color: var(--legacy-500);
  border-color: var(--legacy-300);
}

.page-about .about-lineage-item.is-current {
  color: var(--amber-400);
  border-color: var(--amber-600);
  background: var(--paper-200);
}

.page-about .about-lineage-name {
  font-size: 0.9375rem;
  letter-spacing: 0.04em;
  color: var(--ink-950);
}

.page-about .about-lineage-note {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--text-muted);
}

.page-about .about-table-hint {
  display: block;
  margin: 0 0 8px;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--text-muted);
}

.page-about .about-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--legacy-300);
  background: var(--paper-100);
  -webkit-overflow-scrolling: touch;
}

.page-about .about-table-wrap:focus-visible {
  outline: 2px solid var(--cyan-400);
  outline-offset: 2px;
}

.page-about .about-table {
  width: 100%;
  min-width: 700px;
  border-collapse: collapse;
  font-size: 0.875rem;
}

.page-about .about-table-caption {
  caption-side: top;
  padding: 10px 14px;
  text-align: left;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  font-family: var(--font-mono);
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-table th,
.page-about .about-table td {
  padding: 11px 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--about-rule);
  line-height: 1.6;
}

.page-about .about-table thead th {
  background: var(--ink-900);
  color: var(--paper-100);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  font-weight: 500;
  white-space: nowrap;
}

.page-about .about-table thead th.is-current {
  color: var(--amber-400);
}

.page-about .about-table thead th.is-legacy {
  color: var(--legacy-300);
}

.page-about .about-table tbody th {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-950);
  white-space: nowrap;
  font-weight: 500;
}

.page-about .about-table tbody td {
  color: var(--text-muted);
}

.page-about .about-table tbody td.is-current {
  color: var(--ink-950);
  background: rgba(242, 181, 68, 0.12);
}

.page-about .about-table tbody tr:hover {
  background: rgba(47, 243, 208, 0.1);
}

.page-about .about-table tbody tr:hover td.is-current {
  background: rgba(242, 181, 68, 0.22);
}

.page-about .about-table-foot {
  margin: 12px 0 0;
  font-size: 0.875rem;
  line-height: 1.72;
  color: var(--text-muted);
  max-width: 44em;
}

/* 团队与协作 */
.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
}

.page-about .about-team-roles {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
}

.page-about .about-role {
  padding: 14px 16px;
  background: var(--paper-200);
  border-left: 3px solid var(--amber-400);
}

.page-about .about-role-num {
  margin: 0;
  font-size: 26px;
  line-height: 1;
  color: var(--amber-600);
  letter-spacing: 0.02em;
}

.page-about .about-role-name {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  color: var(--ink-950);
}

.page-about .about-role-text {
  margin: 5px 0 0;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--text-muted);
}

.page-about .about-partners {
  padding: 18px 18px 20px;
  background: var(--ink-900);
  color: var(--paper-100);
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, 0 100%);
}

.page-about .about-partners-title {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan-400);
}

.page-about .about-partner-list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
}

.page-about .about-partner {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(245, 239, 226, 0.16);
  font-size: 0.9375rem;
  color: var(--paper-100);
}

.page-about .about-partner-num {
  font-size: 20px;
  line-height: 1;
  color: var(--amber-400);
  min-width: 2.2em;
}

.page-about .about-partners-text {
  margin: 14px 0 0;
  font-size: 0.875rem;
  line-height: 1.74;
  color: var(--muted-dark);
}

/* 长期观察 */
.page-about .about-observe {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-observe-card {
  padding: 18px 18px 20px;
  background: var(--green-700);
  border-left: 2px solid var(--cyan-400);
}

.page-about .about-observe-card--mark {
  border-left-color: var(--amber-400);
}

.page-about .about-observe-kicker {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cyan-200);
}

.page-about .about-observe-card--mark .about-observe-kicker {
  color: var(--amber-400);
}

.page-about .about-observe-title {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.0625rem;
  line-height: 1.3;
  color: var(--paper-100);
}

.page-about .about-observe-text {
  margin: 7px 0 0;
  font-size: 0.875rem;
  line-height: 1.74;
  color: var(--muted-dark);
}

/* 下一步 */
.page-about .about-next-list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
}

.page-about .about-next-card {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas:
    "kicker arrow"
    "title arrow";
  align-items: center;
  gap: 4px 12px;
  padding: 16px 16px 18px;
  background: var(--paper-200);
  border: 1px solid var(--line);
  text-decoration: none;
  color: var(--ink-950);
  transition: transform var(--dur) ease, border-color var(--dur) ease, box-shadow var(--dur) ease;
}

.page-about .about-next-card:hover,
.page-about .about-next-card:focus-visible {
  transform: translateY(-2px);
  border-color: var(--cyan-400);
  box-shadow: 0 0 0 2px var(--cyan-400);
  outline: none;
}

.page-about .about-next-kicker {
  grid-area: kicker;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--amber-600);
}

.page-about .about-next-title {
  grid-area: title;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  line-height: 1.38;
  color: var(--ink-950);
}

.page-about .about-next-arrow {
  grid-area: arrow;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--green-700);
}

.page-about .about-contact-strip {
  margin-top: var(--about-gap);
  padding: 18px 18px 20px;
  background: var(--ink-950);
  color: var(--paper-100);
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, 0 100%);
}

.page-about .about-contact-text {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.74;
  color: var(--muted-dark);
}

.page-about .about-contact-lines {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin-top: 12px;
}

.page-about .about-contact-link {
  font-size: 0.875rem;
  letter-spacing: 0.03em;
  color: var(--amber-400);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) ease, color var(--dur) ease;
  word-break: break-all;
}

.page-about .about-contact-link:hover,
.page-about .about-contact-link:focus-visible {
  color: var(--paper-100);
  border-bottom-color: var(--cyan-400);
  outline: none;
}

/* 平板与桌面 */
@media (min-width: 620px) {
  .page-about .about-summary {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

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

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

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

@media (min-width: 900px) {
  .page-about .about-layout {
    grid-template-columns: 232px minmax(0, 1fr);
    align-items: start;
  }

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

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

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

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

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
    align-items: start;
  }

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

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

@media (min-width: 1120px) {
  .page-about .about-layout {
    grid-template-columns: 268px minmax(0, 1fr);
    gap: 56px;
  }

  .page-about .about-rail-inner {
    padding-right: 18px;
    border-right: 1px solid var(--about-rule);
  }

  .page-about .about-table-hint {
    display: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-card,
  .page-about .about-next-card,
  .page-about .about-rail-link,
  .page-about .about-contact-link {
    transition: none;
  }

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