.page-about {
  --about-accent: #D4AF37;
  --about-green: #00FF7F;
  --about-primary: #0B1D3A;
  --about-bg-dark: #0D0D0D;
  --about-surface: #1A1A2E;
  --about-text-secondary: #B0B0C0;
  --about-glow: rgba(212, 175, 55, 0.2);
  --about-green-glow: rgba(0, 255, 127, 0.15);
  display: block;
  width: 100%;
  background: linear-gradient(180deg, var(--about-primary) 0%, var(--about-bg-dark) 100%);
  color: #FFFFFF;
  font-family: var(--font-body, 'Helvetica Neue', Arial, 'Noto Sans SC', sans-serif);
}

/* ── 面包屑 ── */
.page-about__breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 1.25rem 0 0.75rem;
  font-size: 0.8rem;
  color: var(--about-text-secondary);
  letter-spacing: 0.04em;
}
.page-about__breadcrumb a {
  color: var(--about-text-secondary);
  text-decoration: none;
  transition: color 0.25s;
}
.page-about__breadcrumb a:hover,
.page-about__breadcrumb a:focus-visible {
  color: var(--about-accent);
  outline: var(--focus-outline, 2px solid #00FF7F);
  outline-offset: 2px;
}
.page-about__breadcrumb-sep {
  color: var(--about-accent);
  font-size: 0.55rem;
  opacity: 0.7;
}

/* ── 横幅 ── */
.page-about__banner {
  position: relative;
  padding: 0.5rem 0 2rem;
}
.page-about__banner-inner {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  align-items: center;
}
.page-about__banner-text {
  flex: 1 1 100%;
}
.page-about__banner-title {
  font-family: var(--font-heading, Georgia, 'Times New Roman', serif);
  font-size: 2.4rem;
  font-weight: 700;
  line-height: 1.15;
  background: linear-gradient(135deg, #FFFFFF 30%, var(--about-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin: 0 0 0.75rem;
  letter-spacing: 0.02em;
}
.page-about__banner-subtitle {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--about-text-secondary);
  max-width: 42em;
  margin: 0;
}
.page-about__banner-visual {
  flex: 0 0 auto;
  width: 100%;
  max-width: 500px;
}
.page-about__banner-img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 12px;
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.6);
  object-fit: cover;
}

/* ── 章节容器 ── */
.page-about__sections {
  padding: 0 0 4rem;
  display: flex;
  flex-direction: column;
  gap: 0;
}

/* ── 单个章节 ── */
.page-about__section {
  position: relative;
  padding: 2.5rem 0;
  border-bottom: 1px solid rgba(212, 175, 55, 0.15);
}
.page-about__section:last-child {
  border-bottom: none;
}
.page-about__section-number {
  font-family: var(--font-heading, Georgia, 'Times New Roman', serif);
  font-size: 3.2rem;
  font-weight: 700;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1.5px rgba(212, 175, 55, 0.4);
  text-stroke: 1.5px rgba(212, 175, 55, 0.4);
  text-shadow: 0 0 20px var(--about-glow);
  margin-bottom: 0.5rem;
  letter-spacing: 0.05em;
  transition: all 0.3s ease;
}
.page-about__section-divider {
  width: 60px;
  height: 2px;
  background: var(--about-accent);
  margin-bottom: 1.5rem;
  border-radius: 2px;
  opacity: 0.6;
}
.page-about__section-content {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}
.page-about__section-text {
  flex: 1 1 100%;
}
.page-about__section-heading {
  font-family: var(--font-heading, Georgia, 'Times New Roman', serif);
  font-size: 1.6rem;
  font-weight: 700;
  color: #FFFFFF;
  margin: 0 0 1rem;
  letter-spacing: 0.03em;
  line-height: 1.25;
}
.page-about__section-body {
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--about-text-secondary);
  margin: 0 0 1rem;
  max-width: 48em;
}
.page-about__section-body:last-child {
  margin-bottom: 0;
}
.page-about__section-visual {
  flex: 0 0 auto;
  width: 100%;
  max-width: 500px;
}
.page-about__section-visual--wide {
  max-width: 700px;
}
.page-about__section-visual--compact {
  max-width: 480px;
}
.page-about__section-img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 10px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  object-fit: cover;
}

/* ── 内联链接 ── */
.page-about__inline-link {
  color: var(--about-accent);
  text-decoration: none;
  border-bottom: 1px solid rgba(212, 175, 55, 0.3);
  transition: border-color 0.25s, color 0.25s;
}
.page-about__inline-link:hover,
.page-about__inline-link:focus-visible {
  color: var(--about-green);
  border-bottom-color: var(--about-green);
  outline: var(--focus-outline, 2px solid #00FF7F);
  outline-offset: 2px;
}

/* ── 更新卡片 ── */
.page-about__update-card {
  background: var(--about-surface);
  border: 1px solid rgba(212, 175, 55, 0.2);
  border-radius: 12px;
  padding: 1.5rem 1.75rem;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
}
.page-about__update-card-tag {
  font-family: var(--font-heading, Georgia, 'Times New Roman', serif);
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  color: var(--about-accent);
  margin-bottom: 1rem;
  text-transform: uppercase;
  opacity: 0.85;
}
.page-about__update-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}
.page-about__update-item {
  position: relative;
  padding-left: 1.2rem;
  font-size: 0.9rem;
  line-height: 1.6;
  color: #E0E0E8;
}
.page-about__update-item::before {
  content: "▸";
  position: absolute;
  left: 0;
  color: var(--about-green);
  font-size: 0.8rem;
}

/* ── container 复用 ── */
.page-about .container {
  max-width: var(--content-max, 1280px);
  margin: 0 auto;
  padding-left: 1.25rem;
  padding-right: 1.25rem;
}

/* ── 桌面 ≥768px ── */
@media (min-width: 768px) {
  .page-about__banner {
    padding: 0.5rem 0 3rem;
  }
  .page-about__banner-inner {
    flex-direction: row;
    align-items: center;
  }
  .page-about__banner-text {
    flex: 1 1 55%;
  }
  .page-about__banner-visual {
    flex: 0 0 42%;
    max-width: 500px;
  }
  .page-about__banner-title {
    font-size: 3.2rem;
  }
  .page-about__banner-subtitle {
    font-size: 1.1rem;
  }

  .page-about__section {
    padding: 3.5rem 0;
  }
  .page-about__section-number {
    font-size: 4.4rem;
  }
  .page-about__section-content {
    flex-direction: row;
    align-items: flex-start;
    gap: 2.5rem;
  }
  .page-about__section-text {
    flex: 1 1 55%;
  }
  .page-about__section-visual {
    flex: 0 0 40%;
    max-width: 500px;
    margin-top: 0.25rem;
  }
  .page-about__section-visual--wide {
    flex: 0 0 50%;
    max-width: 700px;
  }
  .page-about__section-visual--compact {
    flex: 0 0 38%;
    max-width: 480px;
  }
  .page-about__section-heading {
    font-size: 1.85rem;
  }
  .page-about__section-body {
    font-size: 1rem;
  }
}

/* ── 大桌面 ≥1024px ── */
@media (min-width: 1024px) {
  .page-about__banner-title {
    font-size: 3.8rem;
  }
  .page-about__banner-subtitle {
    font-size: 1.2rem;
  }
  .page-about__section-number {
    font-size: 5.2rem;
  }
  .page-about__section-heading {
    font-size: 2.1rem;
  }
  .page-about__section-body {
    font-size: 1.05rem;
  }
  .page-about__section-content {
    gap: 3.5rem;
  }
}