.page-about {
  --about-line: rgba(16, 33, 79, .14);
  --about-line-soft: rgba(16, 33, 79, .09);
  background: var(--paper);
  color: var(--ink);
}

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

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-display);
  color: var(--indigo-deep);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: 22px 0 40px;
  background:
    radial-gradient(120% 92% at 90% -6%, rgba(201, 58, 46, .14), transparent 62%),
    linear-gradient(166deg, rgba(30, 63, 158, .11), rgba(245, 238, 224, 0) 58%),
    var(--paper);
  border-bottom: 2px solid var(--about-line);
}

.page-about .about-hero-grid {
  display: grid;
  gap: 26px;
}

.page-about .about-hero .breadcrumb {
  margin-bottom: 16px;
}

.page-about .about-kicker {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--red-deep);
  margin: 0 0 12px;
}

.page-about h1 {
  font-size: clamp(32px, 7.4vw, 58px);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -.012em;
  margin: 0 0 18px;
  max-width: 15em;
}

.page-about h1::after {
  content: "";
  display: block;
  width: 84px;
  height: 6px;
  margin-top: 18px;
  border-radius: var(--r-pill);
  background: linear-gradient(90deg, var(--red), var(--gold));
}

.page-about .about-lead {
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink);
  max-width: 48ch;
  margin: 0 0 26px;
}

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

.page-about .about-stats li {
  background: var(--cream);
  border: 1px solid var(--about-line);
  border-radius: var(--r-md);
  padding: 12px 14px;
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  color: var(--indigo);
  line-height: 1.15;
}

.page-about .stat-label {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  color: var(--muted);
  line-height: 1.5;
}

.page-about .about-hero-figure {
  margin: 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  border: 2px solid var(--indigo-deep);
  box-shadow: var(--shadow-card);
  background: var(--cream);
}

.page-about .about-hero-figure img {
  width: 100%;
  object-fit: cover;
}

.page-about .about-hero-figure figcaption {
  font-family: var(--font-hand);
  font-size: 15px;
  color: var(--red-deep);
  padding: 10px 16px 12px;
  border-top: 1px dashed var(--about-line);
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  display: grid;
  gap: 0;
  padding-top: 26px;
}

.page-about .about-rail {
  padding: 0 0 14px;
}

.page-about .about-rail-title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--muted);
  margin: 0 0 10px;
}

.page-about .about-rail-list {
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail-list li {
  position: relative;
  flex: 0 0 auto;
}

.page-about .rail-link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 44px;
  padding: 8px 14px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(16, 33, 79, .18);
  background: var(--cream);
  color: var(--indigo-deep);
  font-size: 14px;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 140ms ease, color 140ms ease, border-color 140ms ease;
}

.page-about .rail-idx {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--red-deep);
  letter-spacing: .06em;
}

.page-about .rail-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--gold);
  border: 1.5px solid var(--indigo-deep);
  transition: background-color 140ms ease;
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  background: var(--indigo);
  border-color: var(--indigo-deep);
  color: var(--cream);
}

.page-about .rail-link:hover .rail-idx,
.page-about .rail-link:focus-visible .rail-idx {
  color: var(--gold);
}

.page-about .rail-link:hover .rail-dot,
.page-about .rail-link:focus-visible .rail-dot {
  background: var(--red);
}

.page-about .rail-link:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 2px;
}

/* ---------- 章节通用 ---------- */
.page-about .about-flow {
  min-width: 0;
}

.page-about .about-sec {
  padding: 6px 0 34px;
}

.page-about .sec-head {
  border-top: 2px solid var(--indigo-deep);
  padding-top: 14px;
  margin-bottom: 20px;
}

.page-about .chapter-num {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--cream);
  background: var(--indigo);
  padding: 3px 11px;
  border-radius: var(--r-pill);
  margin-bottom: 12px;
}

.page-about .sec-head h2 {
  font-size: clamp(23px, 4.6vw, 33px);
  font-weight: 900;
  line-height: 1.26;
  margin: 0;
  letter-spacing: -.01em;
}

.page-about .sec-note {
  font-family: var(--font-hand);
  font-size: 15px;
  color: var(--red);
  margin: 8px 0 0;
}

.page-about .prose p {
  font-size: 16px;
  line-height: 1.85;
  margin: 0 0 1em;
  max-width: 60ch;
}

.page-about .prose a {
  color: var(--red-deep);
  text-underline-offset: 3px;
}

.page-about .prose a:hover {
  color: var(--indigo);
}

/* ---------- 来路 ---------- */
.page-about .origin-quote {
  margin: 22px 0 0;
  padding: 18px 20px;
  background: var(--paper-2);
  border-left: 5px solid var(--gold);
  border-radius: 0 var(--r-md) var(--r-md) 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(18px, 3.4vw, 22px);
  line-height: 1.5;
  color: var(--indigo-deep);
  max-width: 34em;
}

/* ---------- 方法条目 ---------- */
.page-about .method-list {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
}

.page-about .method-item {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 10px;
  padding: 18px 4px;
  border-bottom: 1px dashed rgba(16, 33, 79, .22);
  transition: background-color 160ms ease;
}

.page-about .method-item:first-child {
  border-top: 1px dashed rgba(16, 33, 79, .22);
}

.page-about .method-num {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  color: var(--red-deep);
  letter-spacing: .04em;
  padding-top: 2px;
}

.page-about .method-body h3 {
  font-size: 18px;
  font-weight: 800;
  margin: 0 0 7px;
  line-height: 1.4;
}

.page-about .method-body p {
  font-size: 15px;
  line-height: 1.78;
  margin: 0 0 8px;
  max-width: 56ch;
}

.page-about .method-note {
  font-size: 13.5px;
  color: var(--muted);
  padding-left: 11px;
  border-left: 2px solid var(--gold);
  transition: color 160ms ease, border-color 160ms ease;
}

.page-about .method-item:hover,
.page-about .method-item:focus-visible {
  background: rgba(232, 220, 198, .42);
}

.page-about .method-item:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 3px;
  border-radius: var(--r-sm);
}

.page-about .method-item:hover .method-note,
.page-about .method-item:focus-visible .method-note {
  color: var(--green-deep);
  border-left-color: var(--green);
}

.page-about .method-figure {
  margin: 26px 0 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  border: 1px solid var(--about-line);
  background: var(--cream);
}

.page-about .method-figure img {
  width: 100%;
  object-fit: cover;
}

.page-about .method-figure figcaption {
  font-size: 13px;
  color: var(--muted);
  padding: 10px 16px 12px;
  border-top: 1px dashed var(--about-line-soft);
}

/* ---------- 阶段 ---------- */
.page-about .stage-list {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .stage-item {
  background: var(--cream);
  border: 1px solid var(--about-line);
  border-left: 4px solid var(--paper-2);
  border-radius: var(--r-md);
  padding: 16px 18px;
  transition: transform 160ms ease, box-shadow 160ms ease, border-left-color 160ms ease;
}

.page-about .stage-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-card);
  border-left-color: var(--gold);
}

.page-about .stage-item--now {
  border-left-color: var(--red);
  background: linear-gradient(135deg, rgba(30, 63, 158, .08), rgba(201, 58, 46, .09)), var(--cream);
}

.page-about .stage-year {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--red-deep);
  margin-bottom: 6px;
}

.page-about .stage-item h3 {
  font-size: 19px;
  font-weight: 800;
  margin: 0 0 7px;
}

.page-about .stage-item p {
  font-size: 15px;
  line-height: 1.78;
  margin: 0 0 8px;
  max-width: 56ch;
}

.page-about .stage-item .tag {
  display: inline-block;
}

/* 对照条 */
.page-about .stage-compare {
  margin-top: 22px;
  padding: 18px;
  border-radius: var(--r-lg);
  border: 1px solid var(--about-line);
  background: linear-gradient(125deg, rgba(30, 63, 158, .10), rgba(201, 58, 46, .10) 70%, rgba(216, 154, 58, .12));
}

.page-about .compare-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 15px;
  color: var(--indigo-deep);
  margin: 0 0 12px;
}

.page-about .compare-row {
  padding: 10px 0;
  border-bottom: 1px dashed rgba(16, 33, 79, .18);
}

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

.page-about .compare-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 8px;
}

.page-about .compare-name {
  font-size: 14px;
  color: var(--ink);
}

.page-about .compare-vals {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--muted);
  transition: transform 160ms ease;
}

.page-about .compare-vals .arrow {
  color: var(--red);
  font-size: 13px;
}

.page-about .compare-vals .v-new {
  color: var(--red-deep);
}

.page-about .compare-row:hover .compare-vals {
  transform: scale(1.06);
}

.page-about .compare-track {
  display: flex;
  gap: 4px;
  height: 8px;
  border-radius: var(--r-pill);
  background: rgba(16, 33, 79, .10);
  overflow: hidden;
}

.page-about .bar {
  flex: 0 0 auto;
  height: 100%;
  border-radius: var(--r-pill);
  transition: opacity 160ms ease;
}

.page-about .bar--old {
  background: rgba(16, 33, 79, .38);
  opacity: .5;
}

.page-about .bar--new {
  background: linear-gradient(90deg, var(--red), var(--red-deep));
}

.page-about .compare-row:hover .bar--old {
  opacity: 1;
}

.page-about .w-100 { width: 100%; }
.page-about .w-56 { width: 56%; }
.page-about .w-33 { width: 33%; }

.page-about .compare-row--plain {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  gap: 14px;
  margin-top: 18px;
}

.page-about .team-card {
  background: var(--cream);
  border: 1px solid var(--about-line);
  border-radius: var(--r-lg);
  padding: 20px;
  box-shadow: var(--shadow-card);
  transition: transform 160ms ease, border-color 160ms ease;
}

.page-about .team-card:hover {
  transform: translateY(-4px);
  border-color: var(--indigo);
}

.page-about .team-count {
  display: block;
  font-family: var(--font-mono);
  font-size: 38px;
  font-weight: 700;
  line-height: 1;
  color: var(--indigo);
  margin-bottom: 8px;
}

.page-about .team-card:nth-child(2) .team-count {
  color: var(--red-deep);
}

.page-about .team-card:nth-child(3) .team-count {
  color: var(--green-deep);
}

.page-about .team-card h3 {
  font-size: 18px;
  font-weight: 800;
  margin: 0 0 8px;
}

.page-about .team-card p {
  font-size: 14.5px;
  line-height: 1.78;
  margin: 0;
  color: var(--ink);
}

.page-about .team-rhythm {
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px dashed rgba(16, 33, 79, .22);
}

.page-about .team-rhythm p {
  font-size: 16px;
  line-height: 1.85;
  margin: 0;
  max-width: 58ch;
}

/* ---------- 来源 ---------- */
.page-about .source-grid {
  display: grid;
  gap: 22px;
  align-items: start;
}

.page-about .source-figure {
  margin: 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  border: 2px solid var(--paper-2);
  background: var(--cream);
}

.page-about .source-figure img {
  width: 100%;
  object-fit: cover;
}

.page-about .source-figure figcaption {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted);
  padding: 10px 14px 12px;
  border-top: 1px dashed var(--about-line-soft);
  letter-spacing: .04em;
}

/* ---------- 质量 ---------- */
.page-about .quality-list {
  list-style: none;
  margin: 18px 0 22px;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .quality-list li {
  position: relative;
  padding: 12px 16px 12px 44px;
  background: var(--cream);
  border: 1px solid var(--about-line);
  border-radius: var(--r-md);
  font-size: 15px;
  line-height: 1.7;
}

.page-about .quality-list li::before {
  content: "✓";
  position: absolute;
  left: 14px;
  top: 12px;
  width: 20px;
  height: 20px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--green);
  color: var(--cream);
  font-size: 12px;
  font-weight: 700;
}

.page-about .quality-badge {
  display: grid;
  gap: 10px;
  padding: 20px;
  border: 2px solid var(--indigo);
  border-radius: var(--r-lg);
  background: linear-gradient(140deg, rgba(30, 63, 158, .10), rgba(245, 238, 224, 0) 70%);
}

.page-about .badge-year {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--red-deep);
}

.page-about .badge-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  line-height: 1.45;
  color: var(--indigo-deep);
  margin: 0 0 6px;
}

.page-about .badge-desc {
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--ink);
  margin: 0;
  max-width: 52ch;
}

/* ---------- 收尾 ---------- */
.page-about .about-closing {
  margin-top: 72px;
}

.page-about .closing-figure {
  margin: 0;
}

.page-about .closing-figure img {
  width: 100%;
  object-fit: cover;
  border-top: 2px solid var(--about-line);
  border-bottom: 2px solid var(--about-line);
}

.page-about .closing-body {
  padding: 30px 0 46px;
}

.page-about .closing-body h2 {
  font-size: clamp(22px, 4.4vw, 30px);
  font-weight: 900;
  margin: 0 0 12px;
}

.page-about .closing-body p {
  font-size: 16px;
  line-height: 1.85;
  margin: 0 0 20px;
  max-width: 52ch;
}

.page-about .closing-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .closing-actions .btn {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

/* ---------- 断点 ---------- */
@media (min-width: 600px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .method-item {
    grid-template-columns: 46px minmax(0, 1fr);
    gap: 14px;
  }

  .page-about .quality-badge {
    grid-template-columns: auto 1fr;
    align-items: start;
    gap: 20px;
  }

  .page-about .badge-year {
    padding-top: 4px;
  }
}

@media (min-width: 760px) {
  .page-about .about-hero {
    padding: 30px 0 52px;
  }

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

  .page-about .team-card:nth-child(2) {
    margin-top: 34px;
  }

  .page-about .team-card:nth-child(3) {
    margin-top: 16px;
  }

  .page-about .source-grid {
    grid-template-columns: minmax(0, 1fr) 280px;
    gap: 30px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.04fr) minmax(0, .96fr);
    gap: 46px;
    align-items: end;
  }

  .page-about .about-hero-figure {
    transform: rotate(-1.2deg);
  }
}

@media (min-width: 980px) {
  .page-about .about-body {
    grid-template-columns: 152px minmax(0, 1fr);
    gap: 44px;
    padding-top: 34px;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--freq-h) + 26px);
    align-self: start;
    padding-bottom: 0;
  }

  .page-about .about-rail-list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-left: 22px;
    padding-bottom: 0;
  }

  .page-about .about-rail-list::before {
    content: "";
    position: absolute;
    left: 8px;
    top: 14px;
    bottom: 14px;
    border-left: 2px dashed rgba(216, 154, 58, .75);
  }

  .page-about .about-rail-list li {
    flex: 1 1 auto;
    min-width: 0;
  }

  .page-about .rail-link {
    display: flex;
    width: 100%;
    min-height: 44px;
    padding: 10px 0;
    border: 0;
    border-radius: 0;
    background: transparent;
    font-size: 14px;
    transition: color 140ms ease;
  }

  .page-about .rail-link:hover,
  .page-about .rail-link:focus-visible {
    background: transparent;
    color: var(--red-deep);
  }

  .page-about .rail-link:hover .rail-idx,
  .page-about .rail-link:focus-visible .rail-idx {
    color: var(--indigo);
  }

  .page-about .rail-dot {
    position: absolute;
    left: -21px;
    top: 50%;
    transform: translateY(-50%);
  }

  .page-about .rail-link:hover .rail-dot,
  .page-about .rail-link:focus-visible .rail-dot {
    background: var(--red);
    box-shadow: 0 0 0 3px rgba(201, 58, 46, .22);
  }

  .page-about .about-sec {
    padding-bottom: 46px;
  }

  .page-about .sec-head h2 {
    max-width: 22em;
  }

  .page-about .stage-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .stage-compare {
    padding: 22px 24px;
  }

  .page-about .about-closing {
    margin-top: 118px;
  }

  .page-about .closing-body {
    padding-top: 34px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .stage-item,
  .page-about .team-card,
  .page-about .compare-vals,
  .page-about .rail-link,
  .page-about .bar {
    transition: none;
  }

  .page-about .stage-item:hover,
  .page-about .team-card:hover,
  .page-about .compare-row:hover .compare-vals {
    transform: none;
  }

  .page-about .about-hero-figure {
    transform: none;
  }
}