/* =============================================
   page-about 品牌档案 · 页面专属样式
   作用域限定：.page-about
   移动端优先 + 桌面媒体查询
   ============================================= */
.page-about {
  --brand-hero-bg: #0A2B4E;
  --brand-hero-text: #FFFFFF;
  --brand-hero-accent: #D4AF37;
  --version-card-bg: #F5F0E8;
  --version-card-border: rgba(212, 175, 55, 0.35);
  --timeline-line: rgba(212, 175, 55, 0.3);
  --timeline-node-bg: #D4AF37;
  --timeline-node-border: #0A2B4E;
  --service-card-bg: #FFFFFF;
  --service-card-border: rgba(10, 43, 78, 0.12);
  --service-card-shadow: 0 2px 8px rgba(10, 43, 78, 0.06);
  --mission-text: #1C1C1E;
  background: #F5F0E8;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  max-width: var(--container-max, 1280px);
  margin: 0 auto;
  padding: 20px 24px 0;
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-heading);
  font-size: 0.8125rem;
  color: var(--color-primary-medium, #1A5276);
}
.page-about .breadcrumb-link {
  color: var(--color-primary-medium, #1A5276);
  text-decoration: none;
  transition: color var(--transition-standard, 0.3s ease);
}
.page-about .breadcrumb-link:hover,
.page-about .breadcrumb-link:focus-visible {
  color: var(--color-accent-gold, #D4AF37);
}
.page-about .breadcrumb-sep {
  color: var(--color-accent-gold, #D4AF37);
  font-size: 0.75rem;
}
.page-about .breadcrumb-current {
  color: var(--color-text-dark, #1C1C1E);
  font-weight: 600;
}

/* ---------- 品牌概述 ---------- */
.page-about .brand-hero {
  background: var(--brand-hero-bg);
  padding: 48px 0 56px;
  margin: 0 0 0;
}
.page-about .brand-hero__inner {
  display: flex;
  flex-direction: column;
  gap: 36px;
  align-items: center;
}
.page-about .brand-hero__text {
  order: 2;
  text-align: center;
}
.page-about .brand-hero__image {
  order: 1;
  width: 100%;
  max-width: 600px;
}
.page-about .brand-hero__img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 2px solid var(--brand-hero-accent);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.25);
}
.page-about .brand-hero__title {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--brand-hero-text);
  margin: 0 0 8px;
  letter-spacing: 0.04em;
}
.page-about .brand-hero__subtitle {
  font-family: var(--font-heading);
  font-size: 1.125rem;
  font-weight: 500;
  color: var(--brand-hero-accent);
  margin: 0 0 16px;
  letter-spacing: 0.06em;
}
.page-about .brand-hero__desc {
  font-family: var(--font-body);
  font-size: 0.9375rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.88);
  margin: 0 0 20px;
  max-width: 560px;
}
.page-about .brand-hero__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
}
.page-about .brand-hero__tags .tag-gold {
  background: rgba(212, 175, 55, 0.15);
  color: var(--brand-hero-accent);
  border: 1px solid var(--brand-hero-accent);
  padding: 4px 14px;
  font-size: 0.75rem;
  font-family: var(--font-heading);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

/* ---------- 版本亮点 ---------- */
.page-about .version-spotlight {
  padding: 48px 0 40px;
}
.page-about .version-spotlight__card {
  background: var(--version-card-bg);
  border: 1px solid var(--version-card-border);
  border-left: 4px solid var(--color-accent-gold, #D4AF37);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  gap: 24px;
  box-shadow: var(--shadow-card, 0 1px 3px rgba(10,43,78,0.08));
}
.page-about .version-spotlight__badge {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}
.page-about .version-spotlight__badge-num {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-accent-gold, #D4AF37);
  line-height: 1;
  letter-spacing: -0.02em;
}
.page-about .version-spotlight__badge-label {
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--color-primary-medium, #1A5276);
  background: var(--color-accent-gold-light, #F1C40F);
  padding: 2px 10px;
  letter-spacing: 0.06em;
}
.page-about .version-spotlight__body {
  flex: 1;
}
.page-about .version-spotlight__heading {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary-dark, #0A2B4E);
  margin: 0 0 12px;
}
.page-about .version-spotlight__desc {
  font-family: var(--font-body);
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--color-text-dark, #1C1C1E);
  margin: 0 0 20px;
}
.page-about .version-spotlight__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.page-about .version-spotlight__actions .btn-primary {
  background: var(--color-primary-dark, #0A2B4E);
  color: var(--color-text-light, #FFFFFF);
  border: 1px solid var(--color-primary-dark, #0A2B4E);
}
.page-about .version-spotlight__actions .btn-primary:hover,
.page-about .version-spotlight__actions .btn-primary:focus-visible {
  background: var(--color-accent-gold, #D4AF37);
  border-color: var(--color-accent-gold, #D4AF37);
  color: var(--color-primary-dark, #0A2B4E);
}
.page-about .version-spotlight__actions .btn-outline {
  background: transparent;
  color: var(--color-primary-dark, #0A2B4E);
  border: 1px solid var(--color-primary-dark, #0A2B4E);
}
.page-about .version-spotlight__actions .btn-outline:hover,
.page-about .version-spotlight__actions .btn-outline:focus-visible {
  background: var(--color-primary-dark, #0A2B4E);
  color: var(--color-text-light, #FFFFFF);
}

/* ---------- 双栏网格 ---------- */
.page-about .twin-section {
  padding: 8px 0 48px;
}
.page-about .twin-section__grid {
  display: flex;
  flex-direction: column;
  gap: 48px;
}
.page-about .twin-section__left,
.page-about .twin-section__right {
  width: 100%;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline-wrapper__title {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary-dark, #0A2B4E);
  margin: 0 0 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.page-about .timeline-wrapper__title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--color-border-gold, rgba(212,175,55,0.3));
}
.page-about .timeline-chart {
  margin-bottom: 28px;
  border: 1px solid var(--color-border-light, rgba(10,43,78,0.12));
  background: #FFFFFF;
  overflow: hidden;
}
.page-about .timeline-chart__img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}
.page-about .timeline {
  position: relative;
  padding-left: 28px;
  list-style: none;
}
.page-about .timeline::before {
  content: '';
  position: absolute;
  left: 10px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--timeline-line);
}
.page-about .timeline__item {
  position: relative;
  margin-bottom: 0;
}
.page-about .timeline__node {
  position: absolute;
  left: -22px;
  top: 14px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--timeline-node-bg);
  border: 2px solid var(--timeline-node-border);
  z-index: 1;
  transition: transform var(--transition-standard, 0.3s ease),
              box-shadow var(--transition-standard, 0.3s ease);
}
.page-about .timeline__item:hover .timeline__node,
.page-about .timeline__item:focus-within .timeline__node {
  transform: scale(1.25);
  box-shadow: 0 0 0 4px rgba(212, 175, 55, 0.25);
}
.page-about .timeline__content {
  padding: 8px 0 12px;
}
.page-about .timeline__header {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 100%;
  background: none;
  border: none;
  padding: 8px 12px;
  cursor: pointer;
  text-align: left;
  font-family: var(--font-heading);
  color: var(--color-primary-dark, #0A2B4E);
  transition: background var(--transition-standard, 0.3s ease);
  border-radius: 0;
}
.page-about .timeline__header:hover,
.page-about .timeline__header:focus-visible {
  background: rgba(212, 175, 55, 0.08);
}
.page-about .timeline__version {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-accent-gold, #D4AF37);
  min-width: 44px;
  flex-shrink: 0;
}
.page-about .timeline__label {
  font-size: 0.9375rem;
  font-weight: 600;
  flex: 1;
  color: var(--color-text-dark, #1C1C1E);
}
.page-about .timeline__detail {
  font-family: var(--font-body);
  font-size: 0.875rem;
  line-height: 1.65;
  color: var(--color-primary-medium, #1A5276);
  padding: 0 12px 8px 66px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding 0.3s ease;
}
.page-about .timeline__item[data-open] .timeline__detail {
  max-height: 200px;
  padding-top: 6px;
  padding-bottom: 14px;
}
.page-about .timeline__item[data-open] .accordion-icon {
  transform: rotate(45deg);
  color: var(--color-highlight-red, #E74C3C);
}
.page-about .accordion-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  font-size: 1.25rem;
  font-weight: 300;
  color: var(--color-accent-gold, #D4AF37);
  transition: transform 0.35s ease, color 0.35s ease;
  flex-shrink: 0;
  line-height: 1;
}
.page-about .timeline-wrapper__footnote {
  margin-top: 20px;
  text-align: right;
}
.page-about .btn-small {
  padding: 6px 18px;
  font-size: 0.8125rem;
  font-family: var(--font-heading);
  font-weight: 600;
  text-decoration: none;
  display: inline-block;
  transition: all var(--transition-standard, 0.3s ease);
  cursor: pointer;
  border-radius: 0;
}
.page-about .timeline-wrapper__footnote .btn-outline {
  background: transparent;
  color: var(--color-primary-medium, #1A5276);
  border: 1px solid var(--color-primary-medium, #1A5276);
}
.page-about .timeline-wrapper__footnote .btn-outline:hover,
.page-about .timeline-wrapper__footnote .btn-outline:focus-visible {
  background: var(--color-primary-medium, #1A5276);
  color: var(--color-text-light, #FFFFFF);
}

/* ---------- 服务范围 ---------- */
.page-about .services-heading {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary-dark, #0A2B4E);
  margin: 0 0 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.page-about .services-heading::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--color-border-gold, rgba(212,175,55,0.3));
}
.page-about .services-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}
.page-about .service-card {
  perspective: 800px;
  height: 220px;
  cursor: default;
}
.page-about .service-card__inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.5s cubic-bezier(0.23, 1, 0.32, 1);
  transform-style: preserve-3d;
  border: 1px solid var(--service-card-border);
  background: var(--service-card-bg);
  box-shadow: var(--service-card-shadow);
}
.page-about .service-card:hover .service-card__inner,
.page-about .service-card:focus-within .service-card__inner {
  transform: rotateY(180deg);
}
.page-about .service-card__front,
.page-about .service-card__back {
  position: absolute;
  inset: 0;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px 16px;
  text-align: center;
}
.page-about .service-card__front {
  background: var(--service-card-bg);
}
.page-about .service-card__back {
  background: var(--color-primary-dark, #0A2B4E);
  color: var(--color-text-light, #FFFFFF);
  transform: rotateY(180deg);
  font-family: var(--font-body);
  font-size: 0.875rem;
  line-height: 1.7;
  padding: 24px 20px;
}
.page-about .service-card__back p {
  margin: 0;
  max-width: 240px;
}
.page-about .service-card__icon {
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
}
.page-about .service-card__img {
  display: block;
  width: 64px;
  height: 64px;
  object-fit: contain;
  max-width: 100%;
}
.page-about .service-card__title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-primary-dark, #0A2B4E);
  margin: 0 0 6px;
}
.page-about .service-card__tag {
  font-size: 0.6875rem;
  padding: 2px 10px;
  border: 1px solid var(--color-border-gold, rgba(212,175,55,0.4));
  color: var(--color-accent-gold, #D4AF37);
  background: rgba(212, 175, 55, 0.06);
  font-family: var(--font-heading);
  letter-spacing: 0.04em;
}
.page-about .services-footnote {
  margin-top: 20px;
  text-align: right;
}
.page-about .services-footnote .btn-outline {
  background: transparent;
  color: var(--color-primary-medium, #1A5276);
  border: 1px solid var(--color-primary-medium, #1A5276);
}
.page-about .services-footnote .btn-outline:hover,
.page-about .services-footnote .btn-outline:focus-visible {
  background: var(--color-primary-medium, #1A5276);
  color: var(--color-text-light, #FFFFFF);
}

/* ---------- 品牌理念 ---------- */
.page-about .brand-mission {
  padding: 40px 0 56px;
}
.page-about .brand-mission__inner {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
}
.page-about .brand-mission__text {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.8;
  color: var(--mission-text);
  text-align: center;
  margin: 0;
  font-style: italic;
}
.page-about .divider-gold {
  width: 60px;
  height: 1px;
  background: var(--color-accent-gold, #D4AF37);
}

/* =============================================
   桌面端媒体查询 ≥768px
   ============================================= */
@media (min-width: 768px) {
  .page-about .breadcrumb {
    padding: 24px 32px 0;
    font-size: 0.875rem;
  }
  .page-about .brand-hero {
    padding: 56px 0 64px;
  }
  .page-about .brand-hero__inner {
    flex-direction: row;
    gap: 48px;
    align-items: center;
  }
  .page-about .brand-hero__text {
    order: 1;
    text-align: left;
    flex: 1 1 50%;
  }
  .page-about .brand-hero__image {
    order: 2;
    flex: 0 0 45%;
    max-width: 600px;
  }
  .page-about .brand-hero__title {
    font-size: 2.75rem;
  }
  .page-about .brand-hero__subtitle {
    font-size: 1.25rem;
  }
  .page-about .brand-hero__desc {
    font-size: 1rem;
  }
  .page-about .brand-hero__tags {
    justify-content: flex-start;
  }
  .page-about .version-spotlight {
    padding: 40px 0 48px;
  }
  .page-about .version-spotlight__card {
    flex-direction: row;
    align-items: flex-start;
    padding: 36px 40px;
  }
  .page-about .version-spotlight__heading {
    font-size: 1.75rem;
  }
  .page-about .twin-section__grid {
    flex-direction: row;
    gap: 48px;
  }
  .page-about .twin-section__left {
    flex: 1 1 55%;
  }
  .page-about .twin-section__right {
    flex: 1 1 45%;
  }
  .page-about .services-grid {
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }
  .page-about .service-card {
    height: 200px;
  }
  .page-about .service-card__back {
    font-size: 0.8125rem;
  }
  .page-about .timeline-wrapper__title {
    font-size: 1.75rem;
  }
  .page-about .services-heading {
    font-size: 1.75rem;
  }
  .page-about .brand-mission {
    padding: 48px 0 64px;
  }
  .page-about .brand-mission__text {
    font-size: 1.0625rem;
  }
}

/* =============================================
   桌面端媒体查询 ≥1024px
   ============================================= */
@media (min-width: 1024px) {
  .page-about .brand-hero__title {
    font-size: 3.25rem;
  }
  .page-about .brand-hero__subtitle {
    font-size: 1.375rem;
  }
  .page-about .version-spotlight__card {
    padding: 44px 52px;
  }
  .page-about .version-spotlight__heading {
    font-size: 2rem;
  }
  .page-about .twin-section__grid {
    gap: 64px;
  }
  .page-about .service-card {
    height: 220px;
  }
  .page-about .service-card__back {
    font-size: 0.875rem;
    padding: 28px 24px;
  }
  .page-about .service-card__back p {
    max-width: 260px;
  }
}

/* =============================================
   桌面端媒体查询 ≥1280px
   ============================================= */
@media (min-width: 1280px) {
  .page-about .brand-hero__inner {
    gap: 64px;
  }
  .page-about .brand-hero__title {
    font-size: 3.75rem;
  }
  .page-about .twin-section__grid {
    gap: 80px;
  }
  .page-about .service-card {
    height: 240px;
  }
}