.page-about {
  --about-big-size: clamp(5.5rem, 20vw, 13rem);
  --about-gold-glow: rgba(201, 162, 39, 0.24);
  --about-grape-glow: rgba(168, 123, 224, 0.18);
  --about-vine-glow: rgba(107, 180, 169, 0.22);
}

/* ===== 分区基础 ===== */
.page-about .about-section {
  padding: 3rem 0;
}

.page-about .about-section-heading {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.page-about .about-section-index {
  font-family: var(--font-data);
  font-size: var(--text-sm);
  color: var(--color-gold);
  letter-spacing: 0.08em;
  border: 1px solid var(--color-stone);
  border-radius: var(--radius-full);
  padding: 0.25rem 0.65rem;
  white-space: nowrap;
}

.page-about .about-section-heading h2 {
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  color: var(--color-cloud);
  margin: 0;
}

.page-about .about-figure-caption {
  margin-top: 0.75rem;
  font-size: var(--text-sm);
  color: var(--color-stone);
  line-height: 1.6;
}

/* ===== 首屏 Hero ===== */
.page-about .about-hero {
  position: relative;
  padding: 2.5rem 0 3.5rem;
  background:
    radial-gradient(ellipse at 85% 15%, var(--about-grape-glow), transparent 58%),
    radial-gradient(ellipse at 10% 90%, var(--about-vine-glow), transparent 45%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--color-stone), var(--color-gold), transparent);
}

.page-about .about-hero-layout {
  display: grid;
  gap: 2.5rem;
  align-items: center;
}

.page-about .about-hero-copy {
  max-width: 44rem;
}

.page-about .about-hero-copy h1 {
  font-family: var(--font-heading);
  font-size: clamp(var(--text-2xl), 5vw, var(--text-4xl));
  line-height: 1.18;
  color: var(--color-cloud);
  margin: 1rem 0 1.25rem;
}

.page-about .about-hero-copy .lead {
  font-size: var(--text-lg);
  line-height: 1.7;
  color: var(--color-cloud);
  opacity: 0.9;
  max-width: 38rem;
  margin: 0;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.75rem;
}

.page-about .about-hero-stat {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  padding: 2.25rem 1.75rem;
  background:
    radial-gradient(circle at 82% 22%, var(--about-grape-glow), transparent 55%),
    linear-gradient(160deg, var(--color-graphite), var(--color-deep-blue));
  border: 1px solid var(--color-stone);
  border-radius: var(--radius-lg);
  position: relative;
  overflow: hidden;
}

.page-about .about-hero-stat::after {
  content: "";
  position: absolute;
  right: -2.5rem;
  top: -2.5rem;
  width: 8rem;
  height: 8rem;
  border-radius: 50%;
  border: 1.25rem solid var(--about-vine-glow);
  pointer-events: none;
}

.page-about .about-hero-count {
  font-family: var(--font-heading);
  font-size: var(--about-big-size);
  font-weight: 700;
  line-height: 0.9;
  color: var(--color-gold);
  letter-spacing: -0.02em;
}

@supports ((-webkit-background-clip: text) or (background-clip: text)) {
  .page-about .about-hero-count {
    background: linear-gradient(135deg, #F2D27C 0%, var(--color-gold) 48%, var(--color-grape) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
  }
}

.page-about .about-hero-unit {
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  color: var(--color-gold);
  margin-top: 0.5rem;
}

.page-about .about-hero-note {
  font-size: var(--text-sm);
  color: var(--color-grape);
  margin-top: 0.35rem;
}

/* ===== 01 品牌定位 ===== */
.page-about .about-positioning-grid {
  display: grid;
  gap: 2rem;
  align-items: center;
}

.page-about .about-positioning-copy p {
  color: var(--color-cloud);
  line-height: 1.78;
  max-width: 60ch;
  margin: 0 0 1rem;
}

.page-about .about-positioning-copy p:last-of-type {
  margin-bottom: 1.25rem;
}

.page-about .about-positioning-copy .card-link {
  display: inline-block;
  color: var(--color-gold);
  text-decoration: none;
  font-weight: 600;
  font-size: var(--text-base);
  transition: color var(--duration) var(--ease-out), transform var(--duration) var(--ease-out);
}

.page-about .about-positioning-copy .card-link:hover {
  color: var(--color-grape);
  transform: translateX(4px);
}

.page-about .about-positioning-figure,
.page-about .about-cert-figure {
  margin: 0;
}

/* ===== 02/03 双栏区 ===== */
.page-about .about-mid-grid {
  display: grid;
  gap: 3rem;
  align-items: start;
}

/* 左栏：时间线 */
.page-about .about-timeline-image {
  margin-bottom: 2rem;
}

.page-about .about-timeline-list {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.page-about .about-timeline-list::before {
  content: "";
  position: absolute;
  left: 0.4rem;
  top: 1rem;
  bottom: 1rem;
  width: 2px;
  background: linear-gradient(to bottom, var(--color-vine), var(--color-grape), var(--color-gold));
  border-radius: var(--radius-full);
}

.page-about .about-timeline-item {
  position: relative;
  padding-left: 2rem;
}

.page-about .about-timeline-item::before {
  content: "";
  position: absolute;
  left: 0.04rem;
  top: 1.35rem;
  width: 0.78rem;
  height: 0.78rem;
  border-radius: 50%;
  background: var(--color-deep-blue);
  border: 3px solid var(--color-gold);
  box-shadow: 0 0 0 4px var(--about-gold-glow);
}

.page-about .about-timeline-item:first-child::before {
  background: var(--color-gold);
}

.page-about .about-timeline-item .disclosure-summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  color: var(--color-cloud);
  padding: 0.85rem 0.75rem;
  border-radius: var(--radius-md);
  transition: background var(--duration) var(--ease-out), color var(--duration) var(--ease-out);
  width: 100%;
}

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

.page-about .about-timeline-item .disclosure-summary:hover {
  background: var(--color-graphite);
}

.page-about .about-timeline-item .disclosure[open] .disclosure-summary {
  color: var(--color-gold);
}

.page-about .about-year {
  font-family: var(--font-data);
  color: var(--color-gold);
  flex-shrink: 0;
}

.page-about .about-point-title {
  flex: 1;
  min-width: 0;
}

.page-about .about-arrow {
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--color-grape);
  border-bottom: 2px solid var(--color-grape);
  transform: rotate(45deg);
  transition: transform var(--duration) var(--ease-out), border-color var(--duration) var(--ease-out);
  margin-left: auto;
  flex-shrink: 0;
  position: relative;
  top: -2px;
}

.page-about .disclosure[open] .about-arrow {
  transform: rotate(225deg);
  top: 2px;
  border-color: var(--color-gold);
}

.page-about .about-timeline-item .disclosure-content {
  padding: 0.25rem 0.75rem 1rem;
  color: var(--color-cloud);
  opacity: 0.9;
  line-height: 1.7;
  max-width: 52ch;
}

.page-about .about-timeline-item .disclosure-content p {
  margin: 0;
}

/* 右栏：指标卡片墙 */
.page-about .about-metrics-intro {
  color: var(--color-cloud);
  opacity: 0.88;
  line-height: 1.7;
  margin: 0 0 1.5rem;
  max-width: 42ch;
}

.page-about .about-metrics-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.page-about .about-metric-card {
  position: relative;
  background: var(--color-graphite);
  border: 1px solid var(--color-stone);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.25rem 1.5rem;
  transition: transform var(--duration) var(--ease-out), border-color var(--duration) var(--ease-out), box-shadow var(--duration) var(--ease-out);
}

.page-about .about-metric-card::after {
  content: "";
  position: absolute;
  left: 1.25rem;
  right: 1.25rem;
  bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--color-gold), var(--color-grape));
  opacity: 0.55;
  border-radius: var(--radius-full);
  transition: opacity var(--duration) var(--ease-out);
}

.page-about .about-metric-card:hover {
  transform: translateY(-4px) rotate(-0.4deg);
  border-color: var(--color-gold);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.35);
}

.page-about .about-metric-card:hover::after {
  opacity: 1;
}

.page-about .about-metric-value {
  display: block;
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--color-gold);
  line-height: 1.2;
}

.page-about .about-metric-label {
  display: block;
  margin-top: 0.4rem;
  font-weight: 600;
  color: var(--color-cloud);
}

.page-about .about-metric-detail {
  display: block;
  margin-top: 0.5rem;
  font-size: var(--text-sm);
  color: var(--color-cloud);
  opacity: 0.75;
  line-height: 1.55;
}

/* ===== 04 资质与认证 ===== */
.page-about .about-cert-layout {
  display: grid;
  gap: 2rem;
  align-items: center;
}

.page-about .about-cert-copy p {
  color: var(--color-cloud);
  line-height: 1.78;
  max-width: 58ch;
  margin: 0 0 1rem;
}

.page-about .about-cert-copy p:last-child {
  margin-bottom: 0;
}

.page-about .about-cert-shield {
  width: 88px;
  margin-bottom: 1.5rem;
}

.page-about .about-cert-shield svg {
  width: 100%;
  height: auto;
  display: block;
  filter: drop-shadow(0 8px 18px var(--about-gold-glow));
}

/* ===== 05 合作与服务承诺 ===== */
.page-about .about-partner-grid {
  display: grid;
  gap: 2rem;
  align-items: start;
}

.page-about .about-partner-copy p {
  color: var(--color-cloud);
  line-height: 1.78;
  max-width: 60ch;
  margin: 0 0 1rem;
}

.page-about .about-partner-copy p:last-of-type {
  margin-bottom: 1.5rem;
}

.page-about .about-partner-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.page-about .about-partner-aside {
  background:
    linear-gradient(145deg, var(--about-vine-glow), transparent 60%),
    var(--color-graphite);
  border: 1px solid var(--color-stone);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
}

.page-about .about-partner-note-label {
  display: inline-block;
  font-family: var(--font-data);
  font-size: var(--text-sm);
  color: var(--color-grape);
  letter-spacing: 0.08em;
  margin-bottom: 0.35rem;
  text-transform: uppercase;
}

.page-about .about-partner-note p {
  color: var(--color-cloud);
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  line-height: 1.5;
  margin: 0 0 1.25rem;
}

.page-about .about-partner-note p:last-child {
  margin-bottom: 0;
}

/* ===== 图片框架 ===== */
.page-about .image-frame {
  border-radius: var(--radius-md);
  overflow: hidden;
  background: linear-gradient(135deg, var(--color-graphite), var(--color-deep-blue));
}

.page-about .image-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* ===== 桌面端布局 ===== */
@media (min-width: 768px) {
  .page-about .about-hero {
    padding: 3.5rem 0 4.5rem;
  }

  .page-about .about-section {
    padding: 4rem 0;
  }

  .page-about .about-hero-layout {
    grid-template-columns: 1.4fr 0.9fr;
    gap: 3rem;
  }

  .page-about .about-positioning-grid {
    grid-template-columns: 1.1fr 1fr;
    gap: 3.5rem;
  }

  .page-about .about-mid-grid {
    grid-template-columns: 1.1fr 1fr;
    gap: 3.5rem;
  }

  .page-about .about-cert-layout {
    grid-template-columns: 1.2fr 1fr;
    gap: 3.5rem;
  }

  .page-about .about-partner-grid {
    grid-template-columns: 1.4fr 0.9fr;
    gap: 3.5rem;
  }
}

@media (min-width: 1024px) {
  .page-about .about-section {
    padding: 5rem 0;
  }

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

  .page-about .about-metric-card--lead {
    grid-column: 1 / -1;
  }
}