.page-about {
  --about-gold: #C9A64E;
  --about-gold-deep: #8C6D2F;
  --about-line: #2E4A40;
  --about-surface: #12241E;
  --about-primary: #0FBF7F;
  --about-text-dim: #8FBFAD;
  --about-text-mute: #5E8B7C;
  position: relative;
  background: var(--bg-night);
  color: var(--text);
  overflow-x: hidden;
}

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

.page-about .breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 13px;
  color: var(--text-mute);
  margin-bottom: var(--space-3);
}

.page-about__section-kicker {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .12em;
  color: var(--gold);
  text-transform: uppercase;
  margin: 0 0 6px;
}

/* ===== hero ===== */
.page-about__hero {
  position: relative;
  padding: var(--space-3) 0 var(--space-5);
}

.page-about__hero::before,
.page-about__hero::after {
  content: "";
  position: absolute;
  pointer-events: none;
  z-index: 0;
}

.page-about__hero::before {
  top: -60px;
  right: -100px;
  width: 460px;
  height: 460px;
  background: radial-gradient(circle, rgba(15, 191, 127, .18) 0%, transparent 70%);
}

.page-about__hero::after {
  bottom: -40px;
  left: -80px;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, rgba(201, 166, 78, .10) 0%, transparent 70%);
}

.page-about__hero .container {
  position: relative;
  z-index: 1;
}

.page-about__eyebrow {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .14em;
  color: var(--gold);
  text-transform: uppercase;
  margin: 0 0 8px;
}

.page-about__hero-title {
  font-family: var(--font-serif);
  font-size: clamp(28px, 5vw, 46px);
  font-weight: 900;
  line-height: 1.2;
  margin: 0 0 var(--space-2);
  letter-spacing: .01em;
}

.page-about__hero-lead {
  margin: 0 0 var(--space-3);
  color: var(--text-dim);
  font-size: 16px;
  line-height: 1.85;
  max-width: 56ch;
}

.page-about__hero-grid {
  display: grid;
  gap: var(--space-4);
}

.page-about__hero-media {
  margin: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.page-about__hero-media img {
  display: block;
  width: 100%;
}

.page-about__hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: var(--space-3);
}

.page-about__hero .stat-block {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 130px;
  padding: 14px 18px;
  background: rgba(18, 36, 30, .8);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.page-about__hero .stat-block__value {
  font-family: var(--font-mono);
  font-size: 24px;
  line-height: 1.2;
  font-weight: 600;
  color: var(--primary);
}

.page-about__hero .stat-block__label {
  font-size: 13px;
  color: var(--text-mute);
}

/* ===== origin ===== */
.page-about__origin {
  padding: var(--space-4) 0 var(--space-5);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, transparent, rgba(14, 42, 34, .35));
}

.page-about__origin-grid {
  display: grid;
  gap: var(--space-4);
}

.page-about__origin-copy p {
  margin: 0 0 var(--space-3);
  color: var(--text-dim);
  font-size: 15px;
  line-height: 1.85;
}

.page-about__origin-copy .btn {
  margin-top: var(--space-2);
}

.page-about__origin-title {
  font-family: var(--font-serif);
  font-size: clamp(24px, 3vw, 34px);
  font-weight: 900;
  margin: 6px 0 var(--space-3);
  line-height: 1.3;
}

.page-about__origin-aside {
  position: relative;
}

.page-about__boundary-card {
  background: var(--bg-surface);
  border: 1px solid rgba(201, 166, 78, .35);
  border-radius: var(--radius-lg);
  padding: var(--space-3);
  box-shadow: var(--shadow-float);
}

.page-about__boundary-list {
  list-style: none;
  margin: var(--space-2) 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about__boundary-list li {
  position: relative;
  padding-left: 20px;
  color: var(--text-dim);
  font-size: 14px;
  line-height: 1.6;
}

.page-about__boundary-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 8px;
  height: 8px;
  border: 1px solid var(--gold);
  border-radius: 50%;
  background: transparent;
}

/* ===== journey ===== */
.page-about__journey {
  position: relative;
  padding: var(--space-5) 0;
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(14, 42, 34, .55), rgba(11, 31, 26, .2));
}

.page-about__journey::before {
  content: "";
  position: absolute;
  right: -60px;
  top: 140px;
  width: 260px;
  height: 260px;
  background: radial-gradient(circle, rgba(15, 191, 127, .09) 0%, transparent 70%);
  pointer-events: none;
}

.page-about__journey-grid {
  display: grid;
  gap: var(--space-5);
}

.page-about__journey-left {
  min-width: 0;
}

.page-about__journey-left .lead-copy {
  color: var(--text-mute);
  font-size: 15px;
  margin: 0 0 var(--space-3);
  line-height: 1.7;
}

.page-about__journey-title {
  font-family: var(--font-serif);
  font-size: clamp(24px, 3vw, 34px);
  font-weight: 900;
  margin: 6px 0 10px;
  line-height: 1.3;
}

.page-about__journey-right {
  position: relative;
}

/* timeline */
.page-about__timeline {
  position: relative;
  margin: var(--space-4) 0 0;
  padding-left: 34px;
}

.page-about__timeline::before {
  content: "";
  position: absolute;
  left: 14px;
  top: 6px;
  bottom: 40px;
  width: 1px;
  background: linear-gradient(180deg, rgba(201, 166, 78, .7), rgba(46, 74, 64, .4));
}

.page-about__timeline-item {
  position: relative;
  margin-bottom: var(--space-4);
}

.page-about__timeline-rail {
  position: absolute;
  left: -34px;
  top: 6px;
  width: 28px;
  text-align: center;
}

.page-about__timeline-dot {
  position: relative;
  display: inline-block;
  width: 14px;
  height: 14px;
  border: 2px solid var(--gold);
  border-radius: 50%;
  background: var(--bg-night);
  box-shadow: 0 0 0 4px rgba(201, 166, 78, .12);
}

.page-about__timeline-item--sync .page-about__timeline-dot {
  border-radius: 2px;
  transform: rotate(45deg);
}

.page-about__timeline-item--month .page-about__timeline-dot {
  background: var(--gold);
}

.page-about__timeline-item--module .page-about__timeline-dot::before {
  content: "万";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--font-serif);
  font-size: 9px;
  font-weight: 900;
  line-height: 1;
  color: var(--gold);
}

.page-about__timeline-card {
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: border-color .2s ease, box-shadow .2s ease;
}

.page-about__timeline-card:hover {
  border-color: rgba(201, 166, 78, .5);
  box-shadow: var(--shadow-card);
}

.page-about__timeline-heading {
  margin: 0;
}

.page-about__timeline-trigger {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  width: 100%;
  padding: 14px 18px;
  background: transparent;
  border: 0;
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 15px;
  text-align: left;
  cursor: pointer;
}

.page-about__timeline-phase {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--gold);
  text-transform: uppercase;
  white-space: nowrap;
}

.page-about__timeline-title {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 17px;
  line-height: 1.4;
}

.page-about__timeline-plus {
  margin-left: auto;
  align-self: center;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--primary);
}

.page-about__timeline-body {
  padding: 0 18px 18px;
}

.page-about__timeline-content {
  padding-top: 2px;
  border-top: 1px dashed rgba(46, 74, 64, .8);
}

.page-about__timeline-content p {
  margin: 12px 0 0;
  color: var(--text-dim);
  font-size: 15px;
  line-height: 1.75;
}

.page-about__timeline-figure {
  margin: var(--space-4) 0 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--bg-surface);
}

.page-about__timeline-figure img {
  display: block;
  width: 100%;
}

.page-about__timeline-figcaption {
  padding: 10px 14px;
  color: var(--text-mute);
  font-size: 13px;
  background: rgba(14, 42, 34, .6);
}

/* coordinate card */
.page-about__coordinate-card {
  background: linear-gradient(145deg, #12241E, #0E2A22);
  border: 1px solid rgba(201, 166, 78, .25);
  border-radius: var(--radius-lg);
  padding: var(--space-4) var(--space-3);
  box-shadow: var(--shadow-card);
}

.page-about__coordinate-title {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 900;
  margin: 0 0 8px;
}

.page-about__coordinate-desc {
  color: var(--text-mute);
  font-size: 14px;
  line-height: 1.7;
  margin: 0 0 var(--space-2);
}

.page-about__coordinate-list {
  list-style: none;
  margin: var(--space-3) 0;
  padding: 0;
  counter-reset: coord;
}

.page-about__coordinate-list li {
  position: relative;
  counter-increment: coord;
  padding: var(--space-2) 0 var(--space-2) 48px;
  border-top: 1px solid rgba(46, 74, 64, .7);
}

.page-about__coordinate-list li::before {
  content: "0" counter(coord);
  position: absolute;
  left: 0;
  top: var(--space-2);
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--gold);
}

.page-about__coordinate-list strong {
  display: block;
  margin-bottom: 4px;
  color: var(--text);
  font-family: var(--font-serif);
  font-size: 16px;
}

.page-about__coordinate-list span {
  color: var(--text-mute);
  font-size: 14px;
  line-height: 1.6;
}

.page-about__coordinate-card .btn {
  margin-top: var(--space-2);
}

/* ===== quote ===== */
.page-about__quote {
  position: relative;
  background: var(--bg-surface);
  border-top: 1px solid rgba(201, 166, 78, .5);
  border-bottom: 1px solid rgba(201, 166, 78, .5);
  padding: var(--space-5) 0;
}

.page-about__quote::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 18% 50%, rgba(15, 191, 127, .08), transparent 55%);
  pointer-events: none;
}

.page-about__quote-inner {
  position: relative;
  margin: 0;
  max-width: 900px;
}

.page-about__quote-mark {
  display: block;
  font-family: var(--font-serif);
  font-size: 72px;
  line-height: 1;
  color: var(--gold);
  opacity: .55;
  margin-bottom: -14px;
}

.page-about__quote-inner p {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(22px, 4vw, 36px);
  line-height: 1.55;
  color: var(--text);
}

.page-about__quote-inner cite {
  display: block;
  margin-top: var(--space-3);
  color: var(--gold);
  font-family: var(--font-mono);
  font-size: 14px;
  font-style: normal;
  letter-spacing: .08em;
}

/* ===== principles ===== */
.page-about__principles {
  padding: var(--space-5) 0 var(--space-4);
}

.page-about__principles-title {
  font-family: var(--font-serif);
  font-size: clamp(24px, 3vw, 34px);
  font-weight: 900;
  margin: 6px 0 var(--space-3);
  line-height: 1.3;
}

.page-about__principles-grid {
  display: grid;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

.page-about__principle-card {
  position: relative;
  padding: var(--space-3);
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  transition: border-color .2s ease, transform .2s ease;
}

.page-about__principle-card:hover {
  border-color: rgba(201, 166, 78, .55);
  transform: translateY(-2px);
}

.page-about__principle-num {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--gold);
  border: 1px solid rgba(201, 166, 78, .45);
  border-radius: 4px;
  padding: 2px 8px;
  margin-bottom: var(--space-2);
}

.page-about__principle-card h3 {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: 19px;
  margin: 0 0 10px;
}

.page-about__principle-card p {
  color: var(--text-dim);
  font-size: 14px;
  line-height: 1.7;
  margin: 0;
}

.page-about__principle-card a {
  display: inline-block;
  margin-top: 12px;
  color: var(--primary);
  font-size: 14px;
  text-decoration: none;
  border-bottom: 1px solid rgba(15, 191, 127, .4);
}

/* ===== scale ===== */
.page-about__scale {
  position: relative;
  padding: var(--space-5) 0 var(--space-6);
}

.page-about__scale-title {
  font-family: var(--font-serif);
  font-size: clamp(24px, 3vw, 34px);
  font-weight: 900;
  margin: 6px 0 var(--space-3);
  line-height: 1.3;
}

.page-about__scale-wrap {
  display: grid;
  gap: var(--space-4);
  margin-top: var(--space-3);
}

.page-about__scale-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about__scale-item {
  position: relative;
  overflow: hidden;
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: var(--space-3);
}

.page-about__scale-item::after {
  content: "";
  position: absolute;
  right: -22px;
  top: -22px;
  width: 60px;
  height: 60px;
  border: 1px solid rgba(201, 166, 78, .22);
  border-radius: 50%;
}

.page-about__scale-value {
  display: block;
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 600;
  color: var(--primary);
  line-height: 1.2;
}

.page-about__scale-label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  color: var(--text-mute);
  line-height: 1.5;
}

.page-about__scale-figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--bg-surface);
}

.page-about__scale-figure img {
  display: block;
  width: 100%;
}

.page-about__scale-figure figcaption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--text-mute);
  background: rgba(14, 42, 34, .6);
}

.page-about__scale-tags {
  list-style: none;
  margin: var(--space-4) 0 0;
  padding: 0;
  display: grid;
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.page-about__scale-tags li {
  padding: 12px 16px;
  font-size: 14px;
  color: var(--text-dim);
  border-bottom: 1px solid var(--line);
  background: rgba(18, 36, 30, .65);
}

.page-about__scale-tags li:last-child {
  border-bottom: 0;
}

.page-about__scale-tags li::before {
  content: "◆";
  color: var(--gold);
  margin-right: 10px;
  font-size: 11px;
}

.page-about__closing {
  margin-top: var(--space-4);
  padding: var(--space-3);
  border: 1px solid var(--line);
  border-left: 3px solid var(--gold);
  border-radius: var(--radius);
  background: rgba(18, 36, 30, .7);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.page-about__closing p {
  margin: 0;
  color: var(--text-dim);
  font-size: 15px;
  line-height: 1.7;
}

.page-about__closing-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about__closing-actions .btn {
  margin: 0;
}

/* ===== responsive ===== */
@media (min-width: 700px) {
  .page-about__scale-tags {
    grid-template-columns: 1fr 1fr;
  }

  .page-about__scale-tags li:nth-child(5) {
    border-bottom: 1px solid var(--line);
  }
}

@media (min-width: 720px) {
  .page-about__principles-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-3);
  }
}

@media (min-width: 768px) {
  .page-about__closing {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }

  .page-about__closing p {
    max-width: 44ch;
  }
}

@media (min-width: 900px) {
  .page-about__hero {
    padding-top: var(--space-5);
  }

  .page-about__hero-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, .86fr);
    gap: var(--space-5);
    align-items: center;
  }

  .page-about__scale-wrap {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-5);
    align-items: center;
  }
}

@media (min-width: 980px) {
  .page-about__origin-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: var(--space-5);
    align-items: start;
  }

  .page-about__boundary-card {
    position: sticky;
    top: calc(var(--header-h) + 24px);
  }
}

@media (min-width: 1020px) {
  .page-about__journey-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: var(--space-5);
  }

  .page-about__journey-right {
    position: sticky;
    top: 24px;
    align-self: start;
  }
}