/* ===== 品牌概况 page-about 专属样式 ===== */
.page-about {
  --timeline-line: var(--color-secondary);
  --node-size: 2.75rem;
  --node-border-w: 3px;
  --node-bg: var(--color-card);
  --content-gap: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0;
  padding: 1rem 1rem 3rem;
  max-width: var(--max-width);
  margin: 0 auto;
  color: var(--color-text);
  font-family: var(--font-body);
}

/* --- 面包屑 --- */
.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.375rem 0.5rem;
  padding: 0.75rem 0;
  font-size: var(--small);
  color: var(--color-secondary-light);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 2rem;
}
.page-about .breadcrumb a {
  color: var(--color-secondary-light);
  text-decoration: none;
  transition: color var(--transition);
}
.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--color-primary);
}
.page-about .breadcrumb-sep {
  color: var(--color-border);
  user-select: none;
}
.page-about .breadcrumb [aria-current="page"] {
  color: var(--color-text);
  font-weight: 600;
}

/* --- 时间轴节点（移动优先） --- */
.page-about .timeline-node {
  display: flex;
  gap: 1rem;
  position: relative;
  padding: 0 0 3rem;
}
.page-about .timeline-node:last-child {
  padding-bottom: 0;
}

/* 纵向连接线 */
.page-about .timeline-node::before {
  content: "";
  position: absolute;
  left: calc(var(--node-size) / 2 - 2px);
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--timeline-line);
  opacity: 0.35;
  border-radius: 2px;
}
.page-about .timeline-node:first-child::before {
  top: calc(var(--node-size) * 0.3);
}
.page-about .timeline-node:last-child::before {
  bottom: auto;
  height: calc(100% - var(--node-size) * 0.3);
}

/* 节点标记 */
.page-about .node-marker {
  flex-shrink: 0;
  position: relative;
  z-index: 2;
  width: var(--node-size);
  height: var(--node-size);
  border-radius: 50%;
  background: var(--node-bg);
  border: var(--node-border-w) solid var(--timeline-line);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 0.2rem;
  box-shadow: 0 0 0 4px var(--color-bg), 0 0 0 6px var(--color-border);
}
.page-about .node-icon {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 900;
  color: var(--timeline-line);
  letter-spacing: 0.02em;
}

/* 节点内容 */
.page-about .node-content {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

/* --- 标题体系 --- */
.page-about .section-heading {
  font-family: var(--font-heading);
  font-weight: 900;
  line-height: 1.15;
  color: var(--color-primary);
  margin: 0;
}
.page-about h1.section-heading {
  font-size: var(--h1);
}
.page-about h2.section-heading {
  font-size: var(--h2);
}
.page-about .section-subtitle {
  font-size: var(--body);
  color: var(--color-secondary-light);
  margin: -0.5rem 0 0.5rem;
  letter-spacing: 0.04em;
  font-weight: 500;
}

/* --- 品牌故事 --- */
.page-about .story-hero {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--color-card);
  min-height: 260px;
}
.page-about .story-bg {
  display: block;
  width: 100%;
  height: auto;
  min-height: 200px;
  object-fit: cover;
  object-position: center 30%;
}
.page-about .story-overlay {
  position: relative;
  margin: -3rem 1rem 1rem;
  padding: 1.25rem 1.25rem 1rem;
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow);
  z-index: 1;
}
.page-about .story-tagline {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 900;
  color: var(--color-primary);
  margin: 0 0 0.5rem;
}
.page-about .story-desc {
  font-size: var(--body);
  line-height: 1.6;
  margin: 0 0 1rem;
}

/* details / summary 定制 */
.page-about .story-details {
  display: block;
  margin-top: 0.25rem;
}
.page-about .story-summary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  list-style: none;
  cursor: pointer;
  font-size: var(--small);
  font-weight: 700;
  padding: 0.6rem 1.25rem;
  border: none;
  border-radius: 6px;
  background: var(--color-primary);
  color: #fff;
  transition: background var(--transition), box-shadow var(--transition);
  user-select: none;
}
.page-about .story-summary::-webkit-details-marker {
  display: none;
}
.page-about .story-summary:hover,
.page-about .story-summary:focus-visible {
  background: var(--color-primary-light);
  box-shadow: 0 0 0 3px rgba(255, 107, 53, 0.35);
}
.page-about .story-summary::after {
  content: "▾";
  display: inline-block;
  transition: transform var(--transition);
  font-size: 0.8em;
  margin-left: 0.35rem;
}
.page-about .story-details[open] .story-summary::after {
  transform: rotate(180deg);
}
.page-about .expandable-content {
  padding: 1rem 0 0.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}
.page-about .expandable-content p {
  margin: 0;
  line-height: 1.65;
  font-size: var(--body);
}

/* --- 设计理念 --- */
.page-about .philosophy-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}
.page-about .philosophy-card {
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  background: var(--glass-bg);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  border: 1px solid var(--glass-border);
  transition: border-color var(--transition), transform var(--transition);
}
.page-about .philosophy-card:hover {
  border-color: var(--color-primary-light);
  transform: translateY(-2px);
}
.page-about .phil-icon {
  font-size: 1.6rem;
  line-height: 1;
  color: var(--icon-clr, var(--color-primary));
  margin-bottom: 0.15rem;
}
.page-about .philosophy-card h3 {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: var(--h3);
  color: var(--color-text);
  margin: 0;
}
.page-about .philosophy-card p {
  margin: 0;
  font-size: var(--small);
  line-height: 1.6;
  color: rgba(255, 255, 255, 0.85);
}

.page-about .phone-silhouette {
  margin-top: 1rem;
  text-align: center;
}
.page-about .phone-silhouette img {
  max-width: 100%;
  height: auto;
  border-radius: 12px;
  box-shadow: var(--shadow);
  display: block;
  margin: 0 auto;
}

/* --- 内容更新 --- */
.page-about .update-wrapper {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  align-items: flex-start;
}
.page-about .calendar-icon {
  flex-shrink: 0;
  width: 100%;
  max-width: 200px;
}
.page-about .calendar-icon img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 12px;
}
.page-about .update-info {
  padding: 1.25rem;
  background: var(--glass-bg);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  border: 1px solid var(--glass-border);
  width: 100%;
}
.page-about .update-label {
  font-size: var(--small);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-secondary-light);
  margin: 0 0 0.25rem;
  font-weight: 600;
}
.page-about .update-date {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: var(--h3);
  color: var(--color-primary);
  margin: 0 0 0.75rem;
}
.page-about .update-desc {
  font-size: var(--body);
  line-height: 1.6;
  margin: 0 0 0.5rem;
}
.page-about .update-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1rem;
}
.page-about .btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: var(--small);
  font-weight: 600;
  padding: 0.55rem 1.1rem;
  border-radius: 6px;
  text-decoration: none;
  background: transparent;
  border: 1px solid var(--color-secondary);
  color: var(--color-secondary-light);
  transition: background var(--transition), border-color var(--transition), color var(--transition);
}
.page-about .btn-secondary:hover,
.page-about .btn-secondary:focus-visible {
  background: var(--color-secondary);
  color: #fff;
  border-color: var(--color-secondary);
}

/* ===== 桌面增强 (≥768px) ===== */
@media (min-width: 768px) {
  .page-about {
    padding: 2rem 2.5rem 4rem;
    gap: 0;
  }
  .page-about .breadcrumb {
    margin-bottom: 3rem;
  }
  .page-about .timeline-node {
    gap: 2rem;
    padding: 0 0 4rem;
  }
  .page-about .node-marker {
    --node-size: 3.5rem;
    margin-top: 0.1rem;
  }
  .page-about .node-icon {
    font-size: 1.1rem;
  }

  /* 品牌故事 —— 桌面浮层更大 */
  .page-about .story-overlay {
    position: absolute;
    bottom: 1.5rem;
    left: 1.5rem;
    right: 1.5rem;
    margin: 0;
    max-width: 520px;
    padding: 1.5rem 1.75rem;
  }
  .page-about .story-tagline {
    font-size: 1.5rem;
  }

  /* 理念网格：两列 */
  .page-about .philosophy-grid {
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
  }
  .page-about .philosophy-card {
    padding: 1.5rem;
  }

  /* 手机剪影靠右 */
  .page-about .phone-silhouette {
    text-align: right;
    margin-top: 1.5rem;
  }
  .page-about .phone-silhouette img {
    max-width: 440px;
    margin: 0 0 0 auto;
  }

  /* 内容更新：横排 */
  .page-about .update-wrapper {
    flex-direction: row;
    align-items: center;
    gap: 2rem;
  }
  .page-about .calendar-icon {
    max-width: 160px;
  }
  .page-about .update-info {
    flex: 1;
    padding: 1.5rem 1.75rem;
  }
}

/* ===== 宽屏 (≥1024px) ===== */
@media (min-width: 1024px) {
  .page-about {
    padding: 2.5rem 3rem 5rem;
  }
  .page-about .timeline-node {
    gap: 2.5rem;
    padding: 0 0 5rem;
  }
  .page-about .story-overlay {
    max-width: 580px;
    padding: 1.75rem 2rem;
  }
  .page-about .phone-silhouette img {
    max-width: 500px;
  }
  .page-about .calendar-icon {
    max-width: 200px;
  }
}

.page-about {
  --icon-clr: currentColor;
}