.page-about {
  --about-side-w: 160px;
  --about-gap-lg: 48px;
  background: var(--cream);
  color: var(--ink);
  overflow-x: hidden;
}

/* ========== Hero ========== */
.page-about-hero {
  position: relative;
  padding: calc(var(--header-total) + 32px) 0 64px;
  background: var(--navy);
  color: #fff;
  border-bottom: 4px solid var(--gold);
  overflow: hidden;
}

.page-about-hero::before {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: 260px;
  height: 140px;
  background: linear-gradient(135deg, transparent 0 50%, rgba(201, 162, 39, 0.16) 50% 100%);
  pointer-events: none;
  z-index: 0;
}

.page-about-hero-diag {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  pointer-events: none;
  z-index: 0;
}

.page-about-hero-inner {
  position: relative;
  z-index: 1;
}

.page-about-hero .breadcrumb {
  margin-bottom: 28px;
}

.page-about-hero .breadcrumb-link {
  color: var(--soft-gold);
}

.page-about-hero .breadcrumb-list li:last-child {
  color: rgba(255, 255, 255, 0.8);
}

.page-about-hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about-hero-tag {
  color: var(--soft-gold);
  margin-bottom: 12px;
}

.page-about-hero-title {
  font-size: 34px;
  line-height: 1.14;
  margin-bottom: 16px;
  color: #fff;
}

.page-about-hero-subtitle {
  color: rgba(255, 255, 255, 0.82);
  max-width: 560px;
  margin-bottom: 24px;
}

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

.page-about-hero-media {
  margin: 4px 0 8px;
}

.page-about-hero-img {
  width: 100%;
  height: auto;
  border-radius: 4px;
  border: 1px solid rgba(201, 162, 39, 0.45);
  box-shadow: 0 24px 48px rgba(0, 0, 0, 0.4);
}

.page-about-hero-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-top: 40px;
}

.page-about-stat-card {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(201, 162, 39, 0.3);
  border-radius: 4px;
  padding: 16px 14px;
  backdrop-filter: blur(8px);
}

.page-about-stat-num {
  display: block;
  font-size: 32px;
  line-height: 1;
  color: var(--soft-gold);
  font-weight: 700;
}

.page-about-stat-label {
  display: block;
  margin-top: 8px;
  font-size: 12px;
  color: rgba(255, 255, 255, 0.7);
  letter-spacing: 0.06em;
}

/* ========== 共用侧栏标签 ========== */
.page-about-side {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 20px;
}

.page-about-side .vertical-note {
  display: none;
}

/* ========== 章节标题通用 ========== */
.page-about-mission-main h2,
.page-about-journey-title-wrap h2,
.page-about-security-main h2,
.page-about-eco-title-wrap h2,
.page-about-team-main h2,
.page-about-cta h2 {
  font-family: var(--font-title);
  font-size: 28px;
  line-height: 1.22;
  margin: 10px 0 16px;
}

.page-about-mission-main .section-tag,
.page-about-journey-title-wrap .section-tag,
.page-about-security-main .section-tag,
.page-about-eco-title-wrap .section-tag,
.page-about-team-main .section-tag,
.page-about-cta .section-tag {
  color: var(--red);
}

/* ========== 使命与初心 ========== */
.page-about-mission {
  padding: 64px 0;
  background: var(--cream);
}

.page-about-mission-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about-lead {
  font-size: 20px;
  font-weight: 600;
  line-height: 1.45;
  margin: 16px 0 12px;
  border-left: 4px solid var(--gold);
  padding-left: 16px;
}

.page-about-mission-text p {
  margin-bottom: 14px;
  line-height: 1.8;
}

.page-about-mission-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 26px;
}

.page-about-mission-card {
  position: relative;
  padding: 24px 20px 20px;
  border-top: 3px solid var(--gold);
}

.page-about-card-no {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--red);
  margin-bottom: 8px;
  letter-spacing: 0.08em;
}

.page-about-mission-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.page-about-mission-card p {
  line-height: 1.7;
  color: rgba(26, 26, 26, 0.76);
}

/* ========== 发展关键节点 ========== */
.page-about-journey {
  padding: 64px 0 72px;
  background: var(--warm-gray);
}

.page-about-journey-head {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  margin-bottom: 36px;
}

.page-about-journey-title-wrap p:not(.section-tag) {
  line-height: 1.7;
  color: rgba(26, 26, 26, 0.78);
}

.page-about-timeline {
  position: relative;
  margin-left: 16px;
  padding-left: 28px;
}

.page-about-timeline::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  bottom: 8px;
  width: 3px;
  border-radius: 3px;
  background: linear-gradient(180deg, var(--gold), var(--navy) 35%, var(--navy) 75%, var(--red));
}

.page-about-tl-item {
  position: relative;
  margin-bottom: 26px;
}

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

.page-about-tl-item::before {
  content: "";
  position: absolute;
  left: -32px;
  top: 18px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--cream);
  border: 3px solid var(--gold);
}

.page-about-tl-year {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 8px;
}

.page-about-tl-year-num {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  color: var(--navy);
}

.page-about-tl-year-note {
  font-size: 12px;
  color: var(--blue-gray);
  letter-spacing: 0.1em;
}

.page-about-tl-card {
  padding: 20px 20px 18px;
}

.page-about-tl-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
  color: var(--navy);
}

.page-about-tl-card p {
  line-height: 1.75;
  font-size: 15px;
  color: rgba(26, 26, 26, 0.76);
}

/* ========== 数据与安全资质 ========== */
.page-about-security {
  padding: 64px 0;
  background: var(--navy);
  color: #fff;
  position: relative;
}

.page-about-security h2 {
  color: #fff;
}

.page-about-security .page-about-side .exhibit-label,
.page-about-security .page-about-side .vertical-note {
  color: var(--soft-gold);
}

.page-about-security-main .section-tag {
  color: var(--soft-gold);
}

.page-about-security-desc {
  color: rgba(255, 255, 255, 0.78);
  line-height: 1.75;
  margin-bottom: 22px;
}

.page-about-cert-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about-cert-card {
  padding: 20px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(201, 162, 39, 0.35);
  border-radius: 4px;
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.page-about-cert-card:hover {
  transform: translateY(-4px);
  border-color: var(--soft-gold);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.35);
}

.page-about-cert-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  color: var(--navy);
  background: var(--gold);
  padding: 4px 10px;
  border-radius: 2px;
  margin-bottom: 12px;
  letter-spacing: 0.06em;
}

.page-about-cert-card h3 {
  font-size: 18px;
  margin-bottom: 6px;
  color: #fff;
}

.page-about-cert-card p {
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.6;
  font-size: 14px;
}

.page-about-security-notes {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin-top: 24px;
}

.page-about-note-block {
  border-left: 3px solid var(--gold);
  padding-left: 12px;
}

.page-about-note-block .data-number-large {
  display: block;
  font-size: 32px;
  line-height: 1;
  color: var(--soft-gold);
}

.page-about-note-block p {
  margin-top: 6px;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.5;
}

.page-about-security-media {
  margin-top: 28px;
}

.page-about-security-img {
  width: 100%;
  height: auto;
  border-radius: 4px;
  border: 1px solid var(--gold);
}

.page-about-security-caption {
  margin-top: 10px;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.55);
  text-align: center;
}

/* ========== 合作与生态 ========== */
.page-about-ecosystem {
  padding: 64px 0;
  background: var(--cream);
}

.page-about-eco-head {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  margin-bottom: 28px;
}

.page-about-eco-title-wrap p:not(.section-tag) {
  line-height: 1.7;
  color: rgba(26, 26, 26, 0.78);
}

.page-about-eco-media {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about-eco-img {
  width: 100%;
  height: auto;
  border-radius: 4px;
  box-shadow: 0 12px 32px rgba(10, 31, 68, 0.28);
}

.page-about-eco-panel {
  padding: 20px;
  max-width: 100%;
}

.page-about-eco-panel-title {
  display: block;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--navy);
  margin-bottom: 12px;
  border-bottom: 2px solid var(--gold);
  padding-bottom: 8px;
}

.page-about-eco-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.page-about-eco-list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 7px 0;
  border-bottom: 1px dashed var(--light-blue);
  line-height: 1.6;
  font-size: 15px;
}

.page-about-eco-list li:last-child {
  border-bottom: none;
}

.page-about-eco-list strong {
  font-family: var(--font-mono);
  color: var(--red);
  font-size: 18px;
  flex-shrink: 0;
}

/* ========== 团队与协作 ========== */
.page-about-team {
  padding: 64px 0;
  background: var(--warm-gray);
}

.page-about-team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about-team-desc {
  line-height: 1.75;
  margin-bottom: 20px;
}

.page-about-team-accordion {
  display: grid;
  gap: 12px;
}

.page-about-details {
  background: var(--cream);
  border: 1px solid var(--light-blue);
  border-radius: 4px;
}

.page-about-details summary {
  cursor: pointer;
  padding: 16px 20px;
  font-weight: 700;
  font-size: 16px;
  color: var(--navy);
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

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

.page-about-details summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 22px;
  color: var(--gold);
  transition: transform 0.3s ease;
}

.page-about-details[open] summary::after {
  transform: rotate(45deg);
}

.page-about-details p {
  margin: 0;
  padding: 0 20px 18px;
  line-height: 1.7;
  color: rgba(26, 26, 26, 0.8);
  font-size: 15px;
}

/* ========== CTA ========== */
.page-about-cta {
  padding: 64px 0;
  background: var(--navy);
  color: #fff;
  text-align: center;
  border-top: 4px solid var(--gold);
}

.page-about-cta .section-tag {
  color: var(--soft-gold);
}

.page-about-cta h2 {
  color: #fff;
  margin-bottom: 24px;
}

.page-about-cta-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
}

/* ========== 桌面端增强 ========== */
@media (min-width: 768px) {
  .page-about-hero {
    padding: calc(var(--header-total) + 48px) 0 72px;
  }

  .page-about-hero-grid {
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: 48px;
  }

  .page-about-hero-title {
    font-size: 46px;
  }

  .page-about-hero-stats {
    grid-template-columns: repeat(4, 1fr);
    margin-top: 48px;
  }

  .page-about-stat-num {
    font-size: 38px;
  }

  .page-about-side {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
    padding-top: 4px;
  }

  .page-about-side .vertical-note {
    display: inline-block;
    writing-mode: vertical-rl;
    font-size: 12px;
    letter-spacing: 0.12em;
    color: var(--blue-gray);
    transform: rotate(180deg);
  }

  .page-about-mission,
  .page-about-journey,
  .page-about-security,
  .page-about-ecosystem,
  .page-about-team,
  .page-about-cta {
    padding-top: 88px;
    padding-bottom: 88px;
  }

  .page-about-mission-grid,
  .page-about-journey-head,
  .page-about-eco-head,
  .page-about-team-grid {
    grid-template-columns: var(--about-side-w) 1fr;
    gap: var(--about-gap-lg);
    align-items: start;
  }

  .page-about-mission-main h2,
  .page-about-journey-title-wrap h2,
  .page-about-security-main h2,
  .page-about-eco-title-wrap h2,
  .page-about-team-main h2,
  .page-about-cta h2 {
    font-size: 36px;
  }

  .page-about-mission-cards {
    grid-template-columns: 1fr 1fr;
  }

  .page-about-journey-head {
    margin-bottom: 48px;
  }

  .page-about-tl-item {
    display: grid;
    grid-template-columns: 140px 1fr;
    column-gap: 32px;
  }

  .page-about-tl-year {
    flex-direction: column;
    align-items: flex-end;
    gap: 4px;
    margin-top: 16px;
    text-align: right;
  }

  .page-about-tl-year-num {
    font-size: 34px;
  }

  .page-about-tl-card {
    padding: 24px 24px 20px;
  }

  .page-about-security-grid {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 48px;
    align-items: start;
  }

  .page-about-security-main .page-about-side {
    width: auto;
  }

  .page-about-security-media {
    margin-top: 0;
  }

  .page-about-cert-grid {
    grid-template-columns: 1fr 1fr;
  }

  .page-about-eco-head {
    margin-bottom: 32px;
  }
}

@media (min-width: 1024px) {
  .page-about-hero-grid {
    grid-template-columns: 1.05fr 0.95fr;
    gap: 64px;
  }

  .page-about-hero-title {
    font-size: 52px;
  }

  .page-about-eco-media {
    grid-template-columns: 1fr 320px;
    align-items: center;
    gap: 28px;
  }

  .page-about-eco-panel {
    margin-top: 0;
  }

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