.page-about {
  background: var(--color-surface);
  overflow-x: hidden;
}

/* ===== 首屏 ===== */
.page-about .about-hero {
  position: relative;
  background:
    radial-gradient(ellipse at 82% 18%, rgba(0, 229, 255, 0.14), transparent 52%),
    var(--color-bg-deep);
  padding: 3rem 1.25rem 4rem;
  color: #fff;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 229, 255, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.08) 1px, transparent 1px);
  background-size: 32px 32px;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -8%;
  top: -20%;
  width: 38%;
  height: 140%;
  background: repeating-linear-gradient(
    135deg,
    rgba(255, 77, 0, 0.5) 0 2px,
    transparent 2px 10px
  );
  transform: skewX(-8deg);
  pointer-events: none;
}

.page-about .about-hero-inner {
  position: relative;
  z-index: 2;
  max-width: var(--container);
  margin: 0 auto;
}

.page-about .about-hero .breadcrumb {
  margin-bottom: 2.5rem;
}

.page-about .about-hero .breadcrumb-link,
.page-about .about-hero .breadcrumb-item {
  color: rgba(255, 255, 255, 0.72);
}

.page-about .about-hero .breadcrumb-link:hover {
  color: var(--color-primary);
}

.page-about .about-hero .breadcrumb-sep {
  color: rgba(255, 255, 255, 0.38);
}

.page-about .about-hero-index {
  display: inline-block;
  font-size: 0.8125rem;
  letter-spacing: 0.14em;
  color: var(--color-cyan);
  border: 1px solid rgba(0, 229, 255, 0.4);
  padding: 0.375rem 0.75rem;
  margin-bottom: 1rem;
  text-transform: uppercase;
}

.page-about .about-hero-title {
  font-family: var(--font-title);
  font-size: 2.75rem;
  font-weight: 900;
  line-height: 1.06;
  color: #fff;
  margin: 0.5rem 0 0.25rem;
  text-transform: uppercase;
  position: relative;
  display: inline-block;
}

.page-about .about-hero-title::after {
  content: "";
  position: absolute;
  right: -0.625rem;
  bottom: 0.25rem;
  width: 0.5em;
  height: 0.5em;
  background: var(--color-primary);
}

.page-about .about-hero-subtitle {
  font-family: var(--font-title);
  font-size: 1.375rem;
  font-weight: 700;
  color: var(--color-cyan);
  letter-spacing: 0.04em;
  margin: 0 0 1.5rem;
}

.page-about .about-hero-lead {
  max-width: 640px;
  color: rgba(255, 255, 255, 0.82);
  font-size: 1rem;
  line-height: 1.85;
  margin: 0;
}

.page-about .about-hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 2rem;
  margin-top: 2.25rem;
  padding-top: 1.25rem;
  border-top: 1px solid rgba(192, 192, 192, 0.25);
}

.page-about .about-hero-meta-item {
  display: flex;
  flex-direction: column;
  color: rgba(255, 255, 255, 0.65);
  font-size: 0.8125rem;
}

.page-about .about-hero-meta-item .mono {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-gold);
  line-height: 1.2;
}

/* ===== 通用章节 ===== */
.page-about .about-section {
  padding: 4rem 1.25rem;
}

.page-about .about-section-head {
  display: flex;
  align-items: flex-start;
  gap: 0.875rem;
  max-width: var(--container);
  margin: 0 auto 1.5rem;
}

.page-about .about-section-index {
  font-family: var(--font-mono);
  font-size: 3.25rem;
  font-weight: 700;
  line-height: 1;
  color: var(--color-primary);
  flex-shrink: 0;
}

.page-about .about-section-title-wrap {
  border-left: 3px solid var(--color-cyan);
  padding-left: 0.875rem;
}

.page-about .about-section-kicker {
  margin: 0 0 0.25rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

.page-about .about-section-title {
  margin: 0;
  font-family: var(--font-title);
  font-size: 2rem;
  font-weight: 800;
  line-height: 1.15;
  color: var(--color-ink);
}

.page-about .about-section-lead {
  max-width: var(--container);
  margin: -0.25rem auto 1.5rem;
  color: rgba(255, 255, 255, 0.74);
  line-height: 1.8;
  font-size: 0.95rem;
}

.page-about .about-media-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid rgba(192, 192, 192, 0.65);
  background: var(--color-surface);
}

.page-about .about-media-caption {
  margin-top: 0.625rem;
  text-align: right;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

/* ===== 平台概况 ===== */
.page-about .about-intro {
  background: var(--color-surface);
}

.page-about .about-intro-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  max-width: var(--container);
  margin: 0 auto;
}

.page-about .about-intro-copy p {
  color: var(--color-text-body);
  line-height: 1.85;
  margin: 0 0 1rem;
  font-size: 0.98rem;
}

.page-about .about-intro-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.75rem;
  margin-top: 1.75rem;
}

.page-about .about-intro-stat {
  border-top: 2px solid var(--color-primary);
  padding-top: 0.625rem;
}

.page-about .about-intro-stat-value {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.2;
}

.page-about .about-intro-stat-label {
  display: block;
  margin-top: 0.25rem;
  color: var(--color-text-muted);
  font-size: 0.8125rem;
}

.page-about .about-intro-media {
  margin: 0;
}

/* ===== 发展历程 ===== */
.page-about .about-milestones {
  background:
    radial-gradient(ellipse at 18% 82%, rgba(255, 77, 0, 0.1), transparent 42%),
    var(--color-bg-deep);
  color: #fff;
}

.page-about .about-milestones .about-section-title {
  color: #fff;
}

.page-about .about-milestones .about-section-kicker {
  color: var(--color-cyan);
}

.page-about .about-timeline-figure {
  max-width: 900px;
  margin: 0 auto 2.5rem;
}

.page-about .about-milestones .about-media-img {
  border-color: rgba(0, 229, 255, 0.35);
}

.page-about .about-timeline-scroll {
  max-width: var(--container);
  margin: 0 auto;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--color-primary) rgba(255, 255, 255, 0.1);
  padding-bottom: 0.625rem;
}

.page-about .about-timeline-scroll::-webkit-scrollbar {
  height: 6px;
}

.page-about .about-timeline-scroll::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.08);
}

.page-about .about-timeline-scroll::-webkit-scrollbar-thumb {
  background: var(--color-primary);
  border-radius: 2px;
}

.page-about .about-timeline {
  display: flex;
  gap: 1rem;
  min-width: max-content;
  padding: 0 0 0.25rem;
}

.page-about .about-timeline-item {
  flex: 0 0 300px;
  margin: 0;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(192, 192, 192, 0.24);
  border-radius: var(--radius);
  position: relative;
  transition: border-color var(--speed), background var(--speed);
}

.page-about .about-timeline-item[open] {
  border-color: var(--color-primary);
  background: rgba(255, 77, 0, 0.08);
}

.page-about .about-timeline-card {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
  padding: 1.25rem 2.75rem 1.25rem 1.25rem;
  cursor: pointer;
  list-style: none;
  position: relative;
}

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

.page-about .about-timeline-card::-moz-list-bullet {
  font-size: 0;
}

.page-about .about-timeline-year {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.1;
}

.page-about .about-timeline-card-main {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

.page-about .about-timeline-title {
  display: block;
  font-family: var(--font-title);
  font-size: 1.125rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.4;
}

.page-about .about-timeline-desc {
  display: block;
  color: rgba(255, 255, 255, 0.68);
  font-size: 0.875rem;
  line-height: 1.65;
}

.page-about .about-timeline-toggle {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  font-size: 1.25rem;
  color: var(--color-cyan);
  transition: transform var(--speed);
}

.page-about .about-timeline-item[open] .about-timeline-toggle {
  transform: rotate(45deg);
}

.page-about .about-timeline-detail {
  padding: 0 1.25rem 1.25rem;
  border-top: 1px dashed rgba(192, 192, 192, 0.25);
  margin-top: 0.25rem;
}

.page-about .about-timeline-detail p {
  margin: 0.75rem 0 0;
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.875rem;
  line-height: 1.7;
}

.page-about .about-timeline-hint {
  max-width: var(--container);
  margin: 1.25rem auto 0;
  color: var(--color-cyan);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* ===== 服务理念 ===== */
.page-about .about-philosophy {
  background: var(--color-surface);
}

.page-about .about-philosophy-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  max-width: var(--container);
  margin: 0 auto 2.5rem;
}

.page-about .about-philosophy-card {
  background: var(--color-surface);
  border: 1px solid var(--color-silver);
  border-top: 3px solid var(--color-primary);
  padding: 1.5rem;
  position: relative;
}

.page-about .about-philosophy-card-index {
  display: block;
  font-family: var(--font-mono);
  font-size: 2.5rem;
  font-weight: 700;
  line-height: 1;
  color: var(--color-primary);
}

.page-about .about-philosophy-card-title {
  font-family: var(--font-title);
  font-size: 1.5rem;
  font-weight: 800;
  margin: 0.75rem 0 0.5rem;
  color: var(--color-ink);
}

.page-about .about-philosophy-card-text {
  margin: 0;
  color: var(--color-text-muted);
  line-height: 1.75;
  font-size: 0.9375rem;
}

.page-about .about-philosophy-note {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  max-width: var(--container);
  margin: 0 auto;
  align-items: center;
}

.page-about .about-philosophy-note-copy {
  background: var(--color-bg-deep);
  padding: 1.75rem;
  position: relative;
}

.page-about .about-philosophy-note-copy::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-cyan), var(--color-gold));
}

.page-about .about-philosophy-note-kicker {
  margin: 0 0 0.375rem;
  color: var(--color-cyan);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.page-about .about-philosophy-note-title {
  margin: 0 0 1rem;
  font-family: var(--font-title);
  font-size: 1.625rem;
  font-weight: 800;
  color: #fff;
  line-height: 1.3;
}

.page-about .about-philosophy-note-copy p {
  margin: 0 0 0.875rem;
  color: rgba(255, 255, 255, 0.75);
  line-height: 1.8;
  font-size: 0.9375rem;
}

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

.page-about .about-philosophy-note-media {
  margin: 0;
}

/* ===== CTA ===== */
.page-about .about-cta {
  position: relative;
  background:
    radial-gradient(ellipse at 70% 30%, rgba(255, 77, 0, 0.2), transparent 55%),
    var(--color-bg-deep);
  padding: 4rem 1.25rem;
  color: #fff;
  overflow: hidden;
}

.page-about .about-cta::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 6px;
  background: linear-gradient(90deg, var(--color-primary) 0 36%, var(--color-cyan) 36% 63%, var(--color-gold) 63%);
}

.page-about .about-cta-inner {
  position: relative;
  z-index: 1;
  max-width: var(--container);
  margin: 0 auto;
  text-align: center;
}

.page-about .about-cta-kicker {
  margin: 0 0 0.375rem;
  color: var(--color-gold);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.page-about .about-cta-title {
  margin: 0 0 0.75rem;
  font-family: var(--font-title);
  font-size: 2rem;
  font-weight: 900;
  color: #fff;
}

.page-about .about-cta-text {
  max-width: 600px;
  margin: 0 auto 1.75rem;
  color: rgba(255, 255, 255, 0.72);
  line-height: 1.75;
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
}

/* ===== 桌面端布局 ===== */
@media (min-width: 768px) {
  .page-about .about-hero {
    padding: 4.5rem 2rem 6rem;
  }

  .page-about .about-hero-title {
    font-size: 4.5rem;
  }

  .page-about .about-hero-subtitle {
    font-size: 1.75rem;
  }

  .page-about .about-hero-lead {
    font-size: 1.0625rem;
  }

  .page-about .about-section {
    padding: 5rem 2rem;
  }

  .page-about .about-section-index {
    font-size: 5rem;
  }

  .page-about .about-section-title {
    font-size: 2.75rem;
  }

  .page-about .about-intro-grid {
    grid-template-columns: 1.05fr 0.95fr;
    gap: 3rem;
    align-items: center;
  }

  .page-about .about-intro-stat-value {
    font-size: 1.875rem;
  }

  .page-about .about-philosophy-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
  }

  .page-about .about-philosophy-note {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }

  .page-about .about-philosophy-note-copy {
    padding: 2.5rem;
  }

  .page-about .about-cta {
    padding: 5rem 2rem;
  }

  .page-about .about-cta-title {
    font-size: 2.75rem;
  }
}

@media (min-width: 992px) {
  .page-about .about-hero-title {
    font-size: 5.5rem;
  }

  .page-about .about-timeline-item {
    flex-basis: 340px;
  }
}