.page-about {
  --about-rule: rgba(234, 242, 240, .2);
  --about-gap: clamp(20px, 3.2vw, 40px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(20px, 4vw, 42px) 0 clamp(30px, 5vw, 64px);
  background:
    linear-gradient(160deg, rgba(168, 69, 47, .26), rgba(11, 31, 26, 0) 62%),
    linear-gradient(0deg, rgba(44, 42, 74, .22), rgba(11, 31, 26, 0) 55%);
}

.page-about .about-hero-grid {
  display: grid;
  gap: var(--about-gap);
  align-items: end;
}

.page-about .about-lede {
  margin: 18px 0 0;
  max-width: 46ch;
  font-size: var(--step-1);
  line-height: 1.85;
  color: var(--chalk);
}

.page-about .about-lede--sub {
  margin-top: 12px;
  font-size: var(--step-0);
  color: var(--mist);
}

.page-about .about-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.page-about .stat {
  padding: 8px 0 8px 12px;
  border-left: 3px solid var(--flag);
  background: linear-gradient(90deg, rgba(18, 61, 46, .95), rgba(18, 61, 46, 0));
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 1.05rem + 2vw, 2.3rem);
  font-weight: 700;
  line-height: 1.05;
  color: var(--flag);
  letter-spacing: -.02em;
}

.page-about .stat-label {
  display: block;
  margin-top: 6px;
  font-size: var(--step--1);
  line-height: 1.55;
  color: var(--mist);
}

.page-about .about-hero-note {
  margin: 20px 0 0;
  padding-top: 14px;
  border-top: 2px solid var(--about-rule);
  font-size: .82rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  padding-bottom: 0;
}

.page-about .timeline-scroll {
  overflow-x: auto;
  padding: 8px 0 20px;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.page-about .timeline-scroll:focus-visible {
  outline: 2px solid var(--flag);
  outline-offset: 4px;
}

.page-about .timeline-track {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 16px;
  min-width: max-content;
}

.page-about .tl-node {
  scroll-snap-align: start;
  width: min(76vw, 252px);
  padding: 18px 16px 20px;
  background: var(--turf);
  border: 2px solid var(--line-strong);
  border-top: 4px solid var(--flag);
  box-shadow: var(--shadow-mid);
}

.page-about .tl-index {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--step--1);
  letter-spacing: .18em;
  color: var(--mist);
}

.page-about .tl-year {
  display: block;
  margin: 4px 0 10px;
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 1.2rem + 1.6vw, 2.1rem);
  font-weight: 700;
  line-height: 1.1;
  color: var(--chalk);
}

.page-about .tl-title {
  margin: 0 0 8px;
  font-size: var(--step-1);
  line-height: 1.4;
  color: var(--chalk);
}

.page-about .tl-text {
  margin: 0;
  font-size: .92rem;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-cover {
  margin: clamp(18px, 3vw, 34px) auto 0;
  max-width: var(--shell);
}

/* ---------- 里程碑比分带 ---------- */
.page-about .about-milestones {
  margin-top: clamp(30px, 5vw, 66px);
  padding: clamp(30px, 5vw, 62px) 0;
}

.page-about .milestone-title {
  margin: 0 0 22px;
  font-size: var(--step-3);
  line-height: 1.2;
  color: var(--chalk);
  letter-spacing: -.015em;
}

.page-about .milestone-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 20px;
}

.page-about .milestone-item {
  padding-top: 12px;
  border-top: 2px solid rgba(234, 242, 240, .55);
}

.page-about .milestone-year {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--flag);
}

.page-about .milestone-text {
  margin: 8px 0 0;
  font-size: .95rem;
  line-height: 1.75;
  color: rgba(234, 242, 240, .94);
}

/* ---------- 团队 ---------- */
.page-about .about-split {
  display: grid;
  gap: var(--about-gap);
  align-items: start;
}

.page-about .about-text {
  margin: 0 0 14px;
  font-size: var(--step-0);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-team-figure,
.page-about .about-coverage-figure {
  margin: 0;
}

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

.page-about .about-coverage-figure {
  aspect-ratio: 4 / 3;
}

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

.page-about .disclosure {
  margin: 0 0 12px;
  background: var(--night);
  border: 2px solid var(--line-strong);
  box-shadow: var(--shadow-mid);
}

.page-about .disclosure-trigger {
  display: block;
  padding: 14px 16px;
  font-weight: 700;
  font-size: var(--step-0);
  color: var(--chalk);
  cursor: pointer;
  list-style: none;
}

.page-about .disclosure-trigger::-webkit-details-marker {
  display: none;
}

.page-about .disclosure-trigger::after {
  content: "+";
  float: right;
  font-family: var(--font-mono);
  color: var(--flag);
}

.page-about .disclosure[open] .disclosure-trigger::after {
  content: "−";
}

.page-about .disclosure-panel {
  padding: 0 16px 16px;
  font-size: .94rem;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 三条主线 ---------- */
.page-about .line-card {
  position: relative;
  overflow: hidden;
}

.page-about .line-num {
  position: absolute;
  top: 6px;
  right: 14px;
  font-family: var(--font-mono);
  font-size: 3.2rem;
  font-weight: 700;
  line-height: 1;
  color: rgba(234, 242, 240, .1);
  pointer-events: none;
}

.page-about .line-card .card-body p {
  margin: 0;
  color: var(--mist);
  line-height: 1.8;
}

/* ---------- 覆盖范围与标签页 ---------- */
.page-about .about-tabs {
  margin-top: clamp(18px, 3vw, 28px);
}

.page-about .tabs-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .tab {
  padding: 10px 20px;
  font-family: var(--font-mono);
  font-size: .9rem;
  letter-spacing: .1em;
  color: var(--chalk);
  background: transparent;
  border: 2px solid var(--line-strong);
  cursor: pointer;
  transition: background-color .18s ease, color .18s ease, border-color .18s ease;
}

.page-about .tab:hover {
  border-color: var(--flag);
}

.page-about .tab[aria-selected="true"] {
  color: var(--night);
  background: var(--flag);
  border-color: var(--flag);
  box-shadow: var(--shadow-mid);
}

.page-about .tab:focus-visible {
  outline: 2px solid var(--flag);
  outline-offset: 3px;
}

.page-about .tabpanel {
  padding: clamp(16px, 2.6vw, 24px) 0 0;
}

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

.page-about .record-item {
  padding: 4px 0 4px 12px;
  border-left: 3px solid var(--clay);
}

.page-about .record-name {
  margin: 0;
  font-weight: 700;
  color: var(--chalk);
}

.page-about .record-desc {
  margin: 6px 0 0;
  font-size: .92rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 服务承诺 ---------- */
.page-about .service-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .service-item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  padding: 18px;
  background: linear-gradient(160deg, var(--turf), var(--night));
  border: 2px solid var(--line);
}

.page-about .service-num {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.1;
  color: var(--flag);
}

.page-about .service-heading {
  margin: 0 0 6px;
  font-size: var(--step-1);
  line-height: 1.4;
  color: var(--chalk);
}

.page-about .service-text {
  margin: 0;
  font-size: .94rem;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: clamp(22px, 3vw, 34px);
}

.page-about .about-contact {
  margin: 20px 0 0;
  padding-top: 16px;
  border-top: 2px solid var(--about-rule);
  font-size: .85rem;
  line-height: 1.85;
  color: var(--mist);
}

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

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

/* ---------- 断点 ---------- */
@media (min-width: 700px) {
  .page-about .milestone-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

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

  .page-about .tl-node {
    width: 268px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, .75fr);
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
  }

  .page-about .about-split--reverse {
    grid-template-columns: minmax(0, .92fr) minmax(0, 1.08fr);
  }

  .page-about .about-split--reverse .about-coverage-copy {
    order: 2;
  }

  .page-about .about-split--reverse .about-coverage-figure {
    order: 1;
  }

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

@media (min-width: 1100px) {
  .page-about .tl-node {
    width: 292px;
  }

  .page-about .about-lede {
    max-width: 52ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tab {
    transition: none;
  }

  .page-about .timeline-scroll {
    scroll-behavior: auto;
  }
}