/* ==============================================
   page-about 品牌轨迹页面专属样式
   作用域限定：.page-about
   ============================================== */
.page-about {
  --page-about-accent: var(--color-gold, #C9A84C);
  --page-about-highlight: var(--color-red-orange, #D94A3D);
  --page-about-line-color: var(--color-light-gray, #E0D8CE);
  --page-about-dot-size: 18px;
  --page-about-line-width: 3px;
  --page-about-card-radius: var(--radius-card, 12px);
  --page-about-transition: var(--transition-med, 0.35s ease);
}

/* ---------- 容器与布局 ---------- */
.page-about .page-about-inner {
  position: relative;
  padding-top: 1.5rem;
  padding-bottom: 3rem;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  margin-bottom: 1.5rem;
}
.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 0.85rem;
  color: var(--color-medium-brown, #5A3E2B);
}
.page-about .breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin-right: 0.5rem;
  color: var(--color-light-gray, #E0D8CE);
}
.page-about .breadcrumb-item a {
  color: var(--color-medium-brown, #5A3E2B);
  text-decoration: none;
  transition: color var(--transition-fast, 0.2s ease);
}
.page-about .breadcrumb-item a:hover,
.page-about .breadcrumb-item a:focus {
  color: var(--page-about-highlight);
}
.page-about .breadcrumb-item[aria-current="page"] {
  color: var(--color-charcoal, #1A1A1A);
  font-weight: 600;
}

/* ---------- 页面标题 ---------- */
.page-about .page-about-header {
  margin-bottom: 2.5rem;
  position: relative;
}
.page-about .page-about-title {
  font-weight: var(--font-headline, 800);
  font-size: clamp(2rem, 5vw, 3.6rem);
  letter-spacing: -0.02em;
  color: var(--color-dark-brown, #2C1A0E);
  margin: 0 0 0.75rem 0;
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
}
.page-about .page-about-caption {
  color: var(--page-about-accent);
  font-weight: 300;
  font-size: 0.75rem;
  writing-mode: vertical-lr;
  transform: none;
  white-space: nowrap;
  opacity: 0.8;
}
.page-about .page-about-subtitle {
  font-size: 1.05rem;
  line-height: 1.6;
  color: var(--color-medium-brown, #5A3E2B);
  max-width: 680px;
  margin: 0;
}

/* ---------- 时间线包装 ---------- */
.page-about .page-about-timeline-wrapper {
  position: relative;
  padding-left: 2.5rem;
  margin-bottom: 3rem;
}
.page-about .page-about-timeline-wrapper::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 8px;
  bottom: 8px;
  width: var(--page-about-line-width);
  background: linear-gradient(
    to bottom,
    var(--page-about-line-color) 0%,
    var(--page-about-accent) 40%,
    var(--page-about-highlight) 100%
  );
  border-radius: 2px;
  z-index: 0;
}

/* ---------- 时间线节点 ---------- */
.page-about .page-about-timeline-node {
  position: relative;
  margin-bottom: 2rem;
  z-index: 1;
}
.page-about .page-about-node-marker {
  position: absolute;
  left: -2.5rem;
  top: 0.75rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  z-index: 2;
}
.page-about .page-about-node-dot {
  width: var(--page-about-dot-size);
  height: var(--page-about-dot-size);
  border-radius: 50%;
  background: var(--page-about-accent);
  border: 3px solid var(--color-cream, #F5F0E8);
  box-shadow: 0 0 0 2px var(--page-about-accent);
  transition: transform var(--transition-fast, 0.2s ease),
              background var(--transition-fast, 0.2s ease);
}
.page-about .page-about-timeline-node:hover .page-about-node-dot,
.page-about .page-about-timeline-node:focus-within .page-about-node-dot {
  transform: scale(1.25);
  background: var(--page-about-highlight);
  box-shadow: 0 0 0 2px var(--page-about-highlight);
}
.page-about .page-about-node-line {
  width: var(--page-about-line-width);
  height: calc(100% - var(--page-about-dot-size) - 8px);
  background: var(--page-about-line-color);
  margin-top: 4px;
  border-radius: 1px;
}
.page-about .page-about-node-line-last {
  background: linear-gradient(
    to bottom,
    var(--page-about-accent) 0%,
    transparent 100%
  );
  height: 40px;
}

/* ---------- 节点卡片 ---------- */
.page-about .page-about-node-card {
  background: var(--color-white, #FFFFFF);
  border-radius: var(--page-about-card-radius);
  box-shadow: 0 2px 12px var(--color-card-shadow, rgba(44,26,14,0.08));
  transition: box-shadow var(--page-about-transition);
  overflow: hidden;
  cursor: pointer;
}
.page-about .page-about-node-card:hover,
.page-about .page-about-node-card:focus-within {
  box-shadow: 0 6px 24px var(--color-card-shadow-hover, rgba(44,26,14,0.16));
}
.page-about .page-about-node-current .page-about-node-card {
  border-left: 4px solid var(--page-about-highlight);
}

/* ---------- 节点头部 ---------- */
.page-about .page-about-node-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  background: var(--color-cream, #F5F0E8);
  transition: background var(--transition-fast, 0.2s ease);
  user-select: none;
}
.page-about .page-about-node-header:hover {
  background: color-mix(in srgb, var(--color-cream, #F5F0E8) 90%, var(--page-about-accent));
}
.page-about .page-about-node-version {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--color-dark-brown, #2C1A0E);
  letter-spacing: -0.01em;
  min-width: 3.2rem;
}
.page-about .page-about-node-label {
  font-weight: 500;
  font-size: 1rem;
  color: var(--color-charcoal, #1A1A1A);
  flex: 1;
}
.page-about .page-about-node-badge {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background: var(--page-about-highlight);
  color: var(--color-white, #FFFFFF);
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  line-height: 1.4;
}
.page-about .page-about-node-toggle-icon {
  font-size: 1.4rem;
  font-weight: 300;
  color: var(--color-medium-brown, #5A3E2B);
  transition: transform var(--transition-fast, 0.2s ease);
  line-height: 1;
}
.page-about .page-about-node-card[data-open="true"] .page-about-node-toggle-icon {
  transform: rotate(45deg);
}

/* ---------- 节点主体（可折叠） ---------- */
.page-about .page-about-node-body {
  padding: 0 1.25rem;
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--page-about-transition),
              padding var(--page-about-transition);
}
.page-about .page-about-node-card[data-open="true"] .page-about-node-body {
  max-height: 900px;
  padding: 1.25rem;
}
.page-about .page-about-node-desc {
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--color-charcoal, #1A1A1A);
  margin: 0 0 1rem 0;
}

/* ---------- 节点图片 ---------- */
.page-about .page-about-node-image-wrap {
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 1rem;
  background: var(--color-light-gray, #E0D8CE);
}
.page-about .page-about-node-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 480 / 300;
}

/* ---------- 节点标签 ---------- */
.page-about .page-about-node-features {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.75rem;
}

/* ---------- 界面对比区块 ---------- */
.page-about .page-about-compare {
  margin-top: 1.5rem;
  border-top: 1px dashed var(--color-light-gray, #E0D8CE);
  padding-top: 1.25rem;
}
.page-about .page-about-compare-label {
  display: block;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--color-dark-brown, #2C1A0E);
  margin-bottom: 0.75rem;
}
.page-about .page-about-compare-container {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  align-items: flex-start;
}
.page-about .page-about-compare-before,
.page-about .page-about-compare-after {
  flex: 1 1 200px;
  min-width: 160px;
  position: relative;
  border-radius: 8px;
  overflow: hidden;
  background: var(--color-light-gray, #E0D8CE);
}
.page-about .page-about-compare-tag {
  position: absolute;
  top: 0.5rem;
  left: 0.5rem;
  font-size: 0.7rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
  color: var(--color-white, #FFFFFF);
  z-index: 2;
}
.page-about .before-tag {
  background: var(--color-medium-brown, #5A3E2B);
}
.page-about .after-tag {
  background: var(--page-about-highlight);
}
.page-about .page-about-compare-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 480 / 300;
  transition: filter var(--page-about-transition);
}
.page-about .page-about-compare-before:hover .page-about-compare-img,
.page-about .page-about-compare-after:hover .page-about-compare-img {
  filter: brightness(1.05);
}
.page-about .page-about-compare-divider {
  width: 2px;
  background: var(--page-about-accent);
  align-self: stretch;
  flex-shrink: 0;
  border-radius: 1px;
}
.page-about .page-about-compare-desc {
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--color-medium-brown, #5A3E2B);
  margin: 0.75rem 0 0 0;
  flex-basis: 100%;
}

/* ---------- 鼠标悬停遮罩对比 (渐进增强) ---------- */
@media (hover: hover) and (pointer: fine) {
  .page-about .page-about-compare-container[data-compare] {
    position: relative;
    cursor: col-resize;
  }
  .page-about .page-about-compare-container[data-compare] .page-about-compare-before {
    overflow: hidden;
    position: relative;
  }
  .page-about .page-about-compare-container[data-compare] .page-about-compare-before::after {
    content: "";
    position: absolute;
    inset: 0;
    background: var(--color-dark-brown, #2C1A0E);
    opacity: 0;
    transition: opacity var(--transition-fast, 0.2s ease);
    pointer-events: none;
  }
  .page-about .page-about-compare-container[data-compare]:hover .page-about-compare-before::after {
    opacity: 0.3;
  }
}

/* ---------- 版本特性总结 ---------- */
.page-about .page-about-summary {
  margin-bottom: 3rem;
}
.page-about .page-about-summary-title {
  font-weight: var(--font-headline, 800);
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  color: var(--color-dark-brown, #2C1A0E);
  margin: 0 0 1.5rem 0;
  letter-spacing: -0.015em;
}
.page-about .page-about-summary-grid {
  gap: 1.25rem;
}
.page-about .page-about-summary-card {
  padding: 1.5rem;
  border-radius: var(--page-about-card-radius);
  background: var(--color-white, #FFFFFF);
  box-shadow: 0 2px 12px var(--color-card-shadow, rgba(44,26,14,0.08));
  transition: transform var(--transition-fast, 0.2s ease),
              box-shadow var(--transition-fast, 0.2s ease);
  position: relative;
  overflow: hidden;
}
.page-about .page-about-summary-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 28px var(--color-card-shadow-hover, rgba(44,26,14,0.16));
}
.page-about .page-about-summary-num {
  font-weight: 800;
  font-size: 2.4rem;
  line-height: 1;
  color: var(--page-about-accent);
  opacity: 0.3;
  display: block;
  margin-bottom: 0.5rem;
  font-feature-settings: "tnum";
}
.page-about .page-about-summary-card .card-title {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--color-charcoal, #1A1A1A);
  margin: 0 0 0.5rem 0;
}
.page-about .page-about-summary-card .card-text {
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--color-medium-brown, #5A3E2B);
  margin: 0;
}

/* ---------- 品牌装饰纹理 ---------- */
.page-about .page-about-decor {
  position: absolute;
  right: 0;
  top: 8rem;
  width: 120px;
  height: 120px;
  opacity: 0.25;
  pointer-events: none;
  z-index: 0;
  display: none;
}
.page-about .page-about-decor-img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: contain;
}

/* ---------- 内链导航 ---------- */
.page-about .page-about-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-light-gray, #E0D8CE);
}
.page-about .page-about-links .btn {
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9rem;
  padding: 0.6rem 1.4rem;
  border-radius: var(--radius-btn, 6px);
  transition: background var(--transition-fast, 0.2s ease),
              color var(--transition-fast, 0.2s ease),
              border-color var(--transition-fast, 0.2s ease);
}
.page-about .page-about-links .btn-outline {
  border: 2px solid var(--color-dark-brown, #2C1A0E);
  color: var(--color-dark-brown, #2C1A0E);
  background: transparent;
}
.page-about .page-about-links .btn-outline:hover,
.page-about .page-about-links .btn-outline:focus {
  background: var(--color-dark-brown, #2C1A0E);
  color: var(--color-cream, #F5F0E8);
}
.page-about .page-about-links .btn-primary {
  background: var(--page-about-highlight);
  color: var(--color-white, #FFFFFF);
  border: 2px solid var(--page-about-highlight);
}
.page-about .page-about-links .btn-primary:hover,
.page-about .page-about-links .btn-primary:focus {
  background: color-mix(in srgb, var(--page-about-highlight) 80%, #000);
  border-color: color-mix(in srgb, var(--page-about-highlight) 80%, #000);
}

/* ---------- 响应式：移动端优先调整 ---------- */
@media (max-width: 640px) {
  .page-about .page-about-timeline-wrapper {
    padding-left: 1.8rem;
  }
  .page-about .page-about-node-marker {
    left: -1.8rem;
  }
  .page-about .page-about-node-dot {
    width: 14px;
    height: 14px;
  }
  .page-about .page-about-node-header {
    padding: 0.75rem 1rem;
    flex-wrap: wrap;
  }
  .page-about .page-about-node-body {
    padding: 0 1rem;
  }
  .page-about .page-about-node-card[data-open="true"] .page-about-node-body {
    padding: 1rem;
  }
  .page-about .page-about-node-version {
    font-size: 1rem;
    min-width: 2.6rem;
  }
  .page-about .page-about-node-label {
    font-size: 0.9rem;
  }
  .page-about .page-about-node-badge {
    font-size: 0.6rem;
    padding: 0.15rem 0.5rem;
  }
  .page-about .page-about-compare-container {
    flex-direction: column;
  }
  .page-about .page-about-compare-divider {
    width: 100%;
    height: 2px;
  }
  .page-about .page-about-summary-grid {
    grid-template-columns: 1fr;
  }
  .page-about .page-about-decor {
    display: none;
  }
  .page-about .page-about-links {
    flex-direction: column;
  }
  .page-about .page-about-links .btn {
    text-align: center;
  }
}

/* ---------- 桌面端：显示装饰纹理、更宽松布局 ---------- */
@media (min-width: 1024px) {
  .page-about .page-about-inner {
    padding-right: 3rem;
  }
  .page-about .page-about-decor {
    display: block;
    right: -1.5rem;
    top: 6rem;
    width: 160px;
    height: 160px;
  }
  .page-about .page-about-header {
    padding-right: 10rem;
  }
  .page-about .page-about-timeline-wrapper {
    padding-right: 8rem;
  }
  .page-about .page-about-summary-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .page-about .page-about-compare-container {
    flex-wrap: nowrap;
  }
}

/* ---------- 确保容器内不横向溢出 ---------- */
.page-about .container {
  max-width: var(--container-max, 1200px);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1rem;
  padding-right: 1rem;
  box-sizing: border-box;
}

@media (min-width: 768px) {
  .page-about .container {
    padding-left: 1.5rem;
    padding-right: 1.5rem;
  }
}

/* ---------- 共享网格的响应式 ---------- */
.page-about .grid-3 {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

@media (min-width: 641px) {
  .page-about .grid-3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ---------- 折叠交互辅助 ---------- */
.page-about .page-about-node-card[data-open="true"] {
  cursor: default;
}
.page-about .page-about-node-card:not([data-open]) .page-about-node-body {
  max-height: 0;
  padding: 0 1.25rem;
}