/* ===== 品牌概况 (about) 页面专属样式 ===== */
.page-about {
  --ab-hero-height: min(70vh, 600px);
  --ab-bg-blur: blur(4px);
  --ab-card-radius: 12px;
  --ab-transition-speed: 0.4s;
}

/* -------------------- 首屏 -------------------- */
.page-about__hero {
  position: relative;
  min-height: var(--ab-hero-height);
  display: flex;
  align-items: center;
  overflow: hidden;
  background: var(--color-deep-blue, #1A2A3A);
}

.page-about__hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.page-about__hero-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  opacity: 0.45;
  filter: var(--ab-bg-blur);
}

.page-about__hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(115deg, rgba(26,42,58,0.92) 40%, rgba(11,61,61,0.7) 80%);
  z-index: 1;
}

.page-about__hero-content {
  position: relative;
  z-index: 2;
  width: 100%;
  padding: 2rem 1rem;
}

.page-about .breadcrumb {
  margin-bottom: 1rem;
  font-size: 0.85rem;
  color: var(--color-orange, #FF6B35);
}

.page-about .breadcrumb a {
  color: var(--color-light-gray, #F5F5F5);
  text-decoration: none;
}

.page-about .breadcrumb a:hover {
  color: var(--color-orange, #FF6B35);
}

.page-about__hero-layout {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.page-about__hero-text {
  flex: 1 1 55%;
}

.page-about__hero-title {
  font-family: var(--font-heading, 'Helvetica Neue', sans-serif);
  font-weight: 700;
  font-size: clamp(2rem, 5.5vw, 4rem);
  line-height: 1.1;
  color: var(--color-white, #FFFFFF);
  margin: 0 0 1rem;
  letter-spacing: -0.02em;
}

.page-about__hero-sub {
  font-family: var(--font-body, 'Helvetica Neue', sans-serif);
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--color-green, #39FF14);
  margin: 0 0 1.5rem;
  max-width: 32em;
  line-height: 1.5;
}

.page-about__hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.page-about__hero-tag {
  display: inline-block;
  padding: 0.3rem 1rem;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-white, #FFFFFF);
  background: var(--color-orange, #FF6B35);
  border-radius: 999px;
}

.page-about__hero-visual {
  flex: 1 1 40%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.page-about__hero-visual-img {
  width: 100%;
  max-width: 480px;
  height: auto;
  object-fit: contain;
  border-radius: var(--ab-card-radius);
  box-shadow: 0 12px 32px rgba(0,0,0,0.3);
}

/* -------------------- 品牌介绍 -------------------- */
.page-about__mission {
  padding: 4rem 1rem;
}

.page-about__section-title {
  font-family: var(--font-heading, 'Helvetica Neue', sans-serif);
  font-weight: 700;
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--color-deep-blue, #1A2A3A);
  margin: 0 0 2rem;
  position: relative;
  display: inline-block;
}

.page-about__section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background: var(--color-orange, #FF6B35);
  margin-top: 0.5rem;
}

.page-about__section-title--light {
  color: var(--color-white, #FFFFFF);
}

.page-about__section-title--light::after {
  background: var(--color-green, #39FF14);
}

.page-about__mission-grid {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.page-about__mission-text.card {
  background: var(--color-white, #FFFFFF);
  border-radius: var(--ab-card-radius);
  padding: 2rem;
  box-shadow: 0 4px 16px rgba(0,0,0,0.06);
  line-height: 1.7;
  font-size: 1rem;
  color: var(--color-dark-gray, #333333);
  flex: 1;
}

.page-about__mission-text p {
  margin: 0 0 1rem;
}

.page-about__mission-text strong {
  color: var(--color-orange, #FF6B35);
}

.page-about__mission-highlight.card {
  background: var(--color-dark-teal, #0B3D3D);
  border-radius: var(--ab-card-radius);
  padding: 2rem;
  color: var(--color-white, #FFFFFF);
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
  flex: 0 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.page-about__mission-number {
  font-family: var(--font-heading, 'Helvetica Neue', sans-serif);
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--color-green, #39FF14);
  display: block;
}

.page-about__mission-highlight p {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.6;
}

/* -------------------- 核心优势 -------------------- */
.page-about__advantages {
  background: var(--color-deep-blue, #1A2A3A);
  padding: 4rem 1rem;
}

.page-about__advantages-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin-top: 2rem;
}

.page-about__advantage-item.card {
  background: rgba(255,255,255,0.08);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: var(--ab-card-radius);
  padding: 2rem;
  color: var(--color-white, #FFFFFF);
  transition: all var(--ab-transition-speed) ease;
}

.page-about__advantage-item.card:hover {
  background: rgba(255,255,255,0.14);
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.3);
}

.page-about__advantage-icon {
  width: 100%;
  max-width: 200px;
  margin: 0 auto 1rem;
  border-radius: 8px;
  overflow: hidden;
}

.page-about__advantage-img {
  width: 100%;
  height: auto;
  display: block;
}

.page-about__advantage-title {
  font-family: var(--font-heading, 'Helvetica Neue', sans-serif);
  font-weight: 700;
  font-size: 1.3rem;
  color: var(--color-orange, #FF6B35);
  margin: 0 0 0.5rem;
}

.page-about__advantage-desc {
  font-size: 0.95rem;
  line-height: 1.6;
  margin: 0 0 1rem;
  color: rgba(255,255,255,0.85);
}

.page-about__advantage-detail {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.5s ease, opacity 0.3s ease;
  opacity: 0;
}

.page-about__advantage-item[data-expanded] .page-about__advantage-detail {
  max-height: 200px;
  opacity: 1;
}

.page-about__advantage-detail p {
  font-size: 0.9rem;
  color: var(--color-green, #39FF14);
  margin: 0.5rem 0 0;
  padding-top: 0.5rem;
  border-top: 1px solid rgba(57,255,20,0.2);
}

.page-about__advantage-toggle.btn {
  display: inline-block;
  background: var(--color-orange, #FF6B35);
  color: var(--color-white, #FFFFFF);
  border: none;
  padding: 0.5rem 1.5rem;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.3s ease;
}

.page-about__advantage-toggle.btn:hover {
  background: #e55a2b;
}

/* -------------------- 时间线（平台历程） -------------------- */
.page-about__journey {
  padding: 4rem 1rem;
}

.page-about__timeline {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  position: relative;
  padding-left: 2rem;
}

.page-about__timeline::before {
  content: '';
  position: absolute;
  left: 0.6rem;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(to bottom, var(--color-orange, #FF6B35), var(--color-indigo, #4B0082));
}

.page-about__timeline-item {
  position: relative;
  padding-left: 1.5rem;
}

.page-about__timeline-item::before {
  content: '';
  position: absolute;
  left: -1.35rem;
  top: 0.65rem;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-green, #39FF14);
  border: 2px solid var(--color-deep-blue, #1A2A3A);
  z-index: 1;
}

.page-about__timeline-phase {
  font-family: var(--font-mono, 'Courier New', monospace);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--color-orange, #FF6B35);
  text-transform: uppercase;
  letter-spacing: 1px;
  display: block;
  margin-bottom: 0.25rem;
}

.page-about__timeline-content.card {
  background: var(--color-white, #FFFFFF);
  border-radius: var(--ab-card-radius);
  padding: 1.25rem 1.5rem;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}

.page-about__timeline-content h3 {
  font-family: var(--font-heading, 'Helvetica Neue', sans-serif);
  font-weight: 700;
  font-size: 1.1rem;
  margin: 0 0 0.5rem;
  color: var(--color-deep-blue, #1A2A3A);
}

.page-about__timeline-content p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--color-dark-gray, #333333);
}

/* -------------------- 联系方式 -------------------- */
.page-about__contact {
  padding: 4rem 1rem;
  scroll-margin-top: 70px;
}

.page-about__contact-grid {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.page-about__contact-card.card {
  background: var(--color-white, #FFFFFF);
  border-radius: var(--ab-card-radius);
  padding: 2rem;
  box-shadow: 0 4px 16px rgba(0,0,0,0.06);
  border-left: 4px solid var(--color-orange, #FF6B35);
}

.page-about__contact-heading {
  font-family: var(--font-heading, 'Helvetica Neue', sans-serif);
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--color-deep-blue, #1A2A3A);
  margin: 0 0 0.75rem;
}

.page-about__contact-list {
  list-style: none;
  padding: 0;
  margin: 0 0 1rem;
}

.page-about__contact-list li {
  padding: 0.25rem 0;
  font-size: 0.95rem;
  color: var(--color-dark-gray, #333333);
}

.page-about__contact-list a {
  color: var(--color-orange, #FF6B35);
  text-decoration: none;
  font-weight: 600;
}

.page-about__contact-list a:hover {
  text-decoration: underline;
}

.page-about__contact-note {
  font-size: 0.85rem;
  color: #666;
  margin: 0;
  font-style: italic;
}

.page-about__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  margin-top: 2rem;
}

.page-about__cta .btn {
  display: inline-block;
  background: var(--color-orange, #FF6B35);
  color: var(--color-white, #FFFFFF);
  padding: 0.75rem 2rem;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 700;
  text-decoration: none;
  transition: background 0.3s ease, transform 0.2s ease;
}

.page-about__cta .btn:hover {
  background: #e55a2b;
  transform: translateY(-2px);
}

/* -------------------- 响应式 -------------------- */
@media (min-width: 768px) {
  .page-about__hero-layout {
    flex-direction: row;
    align-items: center;
  }

  .page-about__mission-grid {
    flex-direction: row;
  }

  .page-about__mission-text.card {
    flex: 2;
  }

  .page-about__mission-highlight.card {
    flex: 1;
  }

  .page-about__advantages-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about__timeline {
    padding-left: 3rem;
  }

  .page-about__timeline::before {
    left: 1rem;
  }

  .page-about__timeline-item::before {
    left: -2.35rem;
  }

  .page-about__contact-grid {
    flex-direction: row;
  }

  .page-about__contact-card.card {
    flex: 1;
  }
}

@media (min-width: 1024px) {
  .page-about__hero-title {
    font-size: 4rem;
  }

  .page-about__hero-sub {
    font-size: 1.4rem;
  }

  .page-about__advantages-grid {
    gap: 2rem;
  }
}