.page-about {
  --about-line: 1px solid var(--rule);
  --about-body: rgba(247, 242, 231, 0.8);
  background: var(--ink-green);
  color: var(--paper-white);
}

.page-about .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--mist);
}

.page-about h2 {
  margin: 12px 0 0;
  font-size: clamp(26px, 4.2vw, 38px);
  line-height: 1.18;
  font-weight: 900;
  letter-spacing: -0.005em;
}

/* 面包屑 */
.page-about .about-crumb {
  padding-block: clamp(16px, 3vw, 28px) 0;
}

.page-about .breadcrumb {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.page-about .crumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  color: var(--mist);
}

.page-about .crumb-list li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.page-about .crumb-list li + li::before {
  content: "/";
  color: var(--rule-strong);
}

.page-about .crumb-list a {
  color: var(--mist);
  text-decoration: none;
}

.page-about .crumb-list a:hover,
.page-about .crumb-list a:focus-visible {
  color: var(--neon);
}

.page-about .crumb-list [aria-current="page"] {
  color: var(--gold);
}

/* 首屏分屏 */
.page-about .about-hero {
  padding: clamp(24px, 5vw, 48px) 0 clamp(44px, 7vw, 84px);
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(30px, 5vw, 56px);
}

.page-about .about-hero-copy {
  max-width: 40rem;
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-size: clamp(34px, 7.2vw, 60px);
  line-height: 1.08;
  font-weight: 900;
  letter-spacing: -0.012em;
}

.page-about .about-lead {
  margin: 18px 0 0;
  max-width: 34em;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.8;
  color: var(--about-body);
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 26px;
}

.page-about .about-hero-visual {
  position: relative;
  min-width: 0;
}

.page-about .about-hero-photo {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-soft);
  border: var(--about-line);
  background: var(--night-blue);
}

.page-about .about-hero-photo img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.75) brightness(0.62);
}

.page-about .about-hero-photo::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(152deg, rgba(11, 43, 38, 0.28), rgba(14, 34, 56, 0.86));
}

.page-about .about-hero-cards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-mini-card {
  display: grid;
  gap: 5px;
  padding: 14px 16px;
  border-radius: var(--radius-card);
  border: var(--about-line);
  background: rgba(7, 20, 15, 0.78);
}

.page-about .about-mini-card:first-child {
  grid-column: 1 / -1;
}

.page-about .about-mini-num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3.4vw, 28px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--neon);
  font-variant-numeric: tabular-nums;
}

.page-about .about-mini-label {
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.05em;
  color: var(--mist);
}

/* 年份轴 */
.page-about .about-timeline {
  padding: clamp(40px, 7vw, 84px) 0;
  border-top: var(--about-line);
}

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

.page-about .about-aside-text {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-body);
}

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

.page-about .about-jump a {
  padding: 7px 12px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--rule-strong);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--paper-sand);
  text-decoration: none;
  transition: color 160ms ease, border-color 160ms ease;
}

.page-about .about-jump a:hover,
.page-about .about-jump a:focus-visible {
  color: var(--neon);
  border-color: var(--neon);
}

.page-about .about-track {
  position: relative;
  display: grid;
  gap: clamp(14px, 2.6vw, 22px);
  padding-left: 24px;
}

.page-about .about-track::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--neon) 0%, rgba(53, 240, 208, 0.1) 90%);
}

.page-about .about-node {
  position: relative;
  padding: 18px 20px 20px;
  border-radius: var(--radius-card);
  border: var(--about-line);
  background: rgba(14, 34, 56, 0.64);
}

.page-about .about-node::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 24px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--neon);
  box-shadow: 0 0 0 4px rgba(53, 240, 208, 0.14);
}

.page-about .about-node-year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

.page-about .about-node h3 {
  margin: 8px 0 0;
  font-size: clamp(19px, 2.4vw, 24px);
  line-height: 1.32;
  font-weight: 800;
}

.page-about .about-node p:not(.about-node-year) {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--about-body);
}

.page-about .about-node--current {
  background: linear-gradient(152deg, rgba(53, 240, 208, 0.13), rgba(14, 34, 56, 0.82));
  border-color: rgba(53, 240, 208, 0.42);
}

.page-about .about-track-media {
  overflow: hidden;
  border-radius: var(--radius-card);
  border: var(--about-line);
  background: var(--deep-ink);
}

.page-about .about-track-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.82) brightness(0.74);
}

/* 纸沙数据带：团队与筛选 */
.page-about .about-team {
  padding: clamp(44px, 7vw, 88px) 0;
  background: var(--paper-sand);
  color: var(--deep-ink);
}

.page-about .about-team .eyebrow {
  color: rgba(11, 43, 38, 0.62);
}

.page-about .about-team-intro {
  max-width: 46rem;
}

.page-about .about-team h2 {
  color: var(--deep-ink);
}

.page-about .about-team-text {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(7, 20, 15, 0.78);
}

.page-about .about-team-frame {
  margin-top: clamp(22px, 4vw, 34px);
  overflow: hidden;
  border-radius: var(--radius-card);
  background: var(--ink-green);
}

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

.page-about .about-roles {
  margin-top: clamp(22px, 4vw, 32px);
}

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

.page-about .filter-btn {
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(11, 43, 38, 0.26);
  background: transparent;
  color: var(--deep-ink);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: background 160ms ease, color 160ms ease, border-color 160ms ease;
}

.page-about .filter-btn:hover {
  border-color: var(--ink-green);
}

.page-about .filter-btn:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 2px;
}

.page-about .filter-btn[aria-pressed="true"],
.page-about .filter-btn.is-active {
  background: var(--ink-green);
  border-color: var(--ink-green);
  color: var(--paper-white);
}

.page-about .filter-count {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(11, 43, 38, 0.6);
}

.page-about .about-role-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 18px;
}

.page-about .about-role {
  padding: 18px;
  border-radius: 16px;
  border: 1px solid rgba(11, 43, 38, 0.14);
  background: var(--paper-white);
  transition: transform 180ms ease, border-color 180ms ease;
}

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

.page-about .about-role-index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: rgba(11, 43, 38, 0.52);
}

.page-about .about-role h3 {
  margin: 8px 0 0;
  font-size: 18px;
  line-height: 1.35;
  color: var(--deep-ink);
}

.page-about .about-role p:not(.about-role-index) {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.72;
  color: rgba(7, 20, 15, 0.76);
}

.page-about [data-filter-item][hidden] {
  display: none;
}

/* 覆盖范围 */
.page-about .about-coverage {
  padding: clamp(44px, 7vw, 88px) 0;
}

.page-about .about-coverage-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 5vw, 52px);
}

.page-about .about-coverage-copy p {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-body);
}

.page-about .about-project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-project-tags .tag {
  display: inline-flex;
  padding: 6px 12px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--rule-strong);
  font-size: 13px;
  color: var(--paper-sand);
}

.page-about .about-note {
  margin: 18px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--gold);
  font-size: 13px;
  line-height: 1.75;
  letter-spacing: 0.02em;
  color: var(--mist);
}

.page-about .about-coverage-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-coverage-stats li {
  display: grid;
  gap: 6px;
  padding: 16px;
  border-radius: var(--radius-card);
  border: var(--about-line);
  background: rgba(232, 220, 198, 0.08);
}

.page-about .about-big {
  font-family: var(--font-mono);
  font-size: clamp(28px, 5vw, 40px);
  font-weight: 700;
  line-height: 1;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}

.page-about .about-big-label {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--mist);
}

/* 协作与记录 */
.page-about .about-governance {
  padding: clamp(44px, 7vw, 88px) 0;
  background: var(--night-blue);
  border-top: var(--about-line);
}

.page-about .about-governance-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 48px);
}

.page-about .about-governance-copy p {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-body);
}

.page-about .about-linkline {
  margin-top: 18px;
}

.page-about .about-inline-link {
  font-size: 14px;
  letter-spacing: 0.02em;
  color: var(--neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 240, 208, 0.32);
  padding-bottom: 2px;
}

.page-about .about-inline-link:hover,
.page-about .about-inline-link:focus-visible {
  border-bottom-color: var(--neon);
}

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

.page-about .about-rule-list li {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 12px;
  padding: 16px 0;
  border-top: 1px dashed var(--rule);
}

.page-about .about-rule-list li:last-child {
  border-bottom: 1px dashed var(--rule);
}

.page-about .about-rule-num {
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .about-rule-list h3 {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 17px;
  letter-spacing: 0.01em;
  color: var(--paper-white);
}

.page-about .about-rule-list p {
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist);
}

/* 继续阅读 */
.page-about .about-next {
  padding: clamp(44px, 7vw, 88px) 0 clamp(52px, 8vw, 96px);
}

.page-about .about-next-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-next-card {
  display: block;
  padding: 20px;
  border-radius: var(--radius-card);
  border: var(--about-line);
  background: rgba(14, 34, 56, 0.6);
  color: inherit;
  text-decoration: none;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.page-about .about-next-card:hover,
.page-about .about-next-card:focus-visible {
  transform: translateY(-3px);
  border-color: var(--neon);
  background: rgba(14, 34, 56, 0.92);
}

.page-about .about-next-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

.page-about .about-next-card h3 {
  margin: 10px 0 0;
  font-size: 19px;
  line-height: 1.35;
}

.page-about .about-next-card p {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--about-body);
}

.page-about .about-contact-line {
  margin-top: 26px;
  padding-top: 20px;
  border-top: 1px dashed var(--rule);
  font-size: 14px;
  line-height: 1.85;
  color: var(--about-body);
}

.page-about .about-contact-line p {
  margin: 0;
}

.page-about .about-contact-line a {
  color: var(--neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 240, 208, 0.32);
}

.page-about .about-contact-line a:hover,
.page-about .about-contact-line a:focus-visible {
  border-bottom-color: var(--neon);
}

/* 入场显现 */
.page-about [data-reveal].is-visible {
  animation: about-reveal 420ms ease both;
}

@keyframes about-reveal {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about [data-reveal].is-visible {
    animation: none;
  }
  .page-about .about-role,
  .page-about .about-next-card,
  .page-about .filter-btn {
    transition: none;
  }
  .page-about .about-role:hover,
  .page-about .about-next-card:hover,
  .page-about .about-next-card:focus-visible {
    transform: none;
  }
}

@media (min-width: 640px) {
  .page-about .about-hero-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    margin: -40px 0 0;
    padding: 0 14px;
  }
  .page-about .about-mini-card:first-child {
    grid-column: auto;
  }
  .page-about .about-mini-card:nth-child(2) {
    transform: translateY(-10px);
  }
  .page-about .about-mini-card:nth-child(3) {
    transform: translateY(6px);
  }
  .page-about .about-role-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-next-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 880px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
    align-items: start;
  }
  .page-about .about-aside {
    position: sticky;
    top: 96px;
  }
  .page-about .about-coverage-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }
  .page-about .about-governance-grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 6fr);
    align-items: start;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: start;
  }
}

@media (min-width: 1024px) {
  .page-about .about-role-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-coverage-stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1080px) {
  .page-about .about-next-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}