/* ===== 页面专属样式：品牌故事 (.page-about) ===== */
.page-about {
  --page-bg-start: #1a0505;
  --page-bg-end: #1a1a1a;
  --page-timeline-node-size: 1rem;
  --page-timeline-line-width: 2px;
  --page-chapter-gap: 2rem;
  --page-content-max: 720px;

  background: linear-gradient(160deg, var(--page-bg-start), var(--page-bg-end));
  color: var(--color-light-gray);
  font-family: var(--font-body);
  line-height: 1.7;
  position: relative;
  min-height: 100vh;
  padding-bottom: 3rem;
}

/* ---- 滚动进度条 (右侧) ---- */
.page-about__progress {
  position: fixed;
  right: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--color-dark-gray);
  z-index: 100;
  pointer-events: none;
  opacity: 0.6;
}
.page-about__progress::after {
  content: '';
  display: block;
  width: 100%;
  height: 0;
  background: var(--color-gold);
  transition: height 0.1s ease;
}

/* ---- Hero 区域 ---- */
.page-about__hero {
  position: relative;
  overflow: hidden;
  max-height: 70vh;
  min-height: 320px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.page-about__hero-visual {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.page-about__hero-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.page-about__hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(139,0,0,0.75) 0%, rgba(26,26,26,0.85) 100%);
  mix-blend-mode: multiply;
}
.page-about__hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 3rem 1.5rem;
  max-width: var(--content-max-width);
  width: 100%;
}
.page-about__breadcrumb {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  margin-bottom: 1.5rem;
  color: var(--color-light-gray);
}
.page-about__breadcrumb-link {
  color: var(--color-gold);
  text-decoration: none;
  transition: opacity 0.2s;
}
.page-about__breadcrumb-link:hover {
  opacity: 0.8;
  text-decoration: underline;
}
.page-about__breadcrumb-sep {
  color: var(--color-light-gray);
  font-weight: 700;
}
.page-about__breadcrumb-current {
  color: var(--color-white);
  font-weight: 600;
}
.page-about__hero-title {
  font-family: var(--font-heading);
  font-size: clamp(2.2rem, 8vw, 4rem);
  color: var(--color-white);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin: 0 0 0.75rem;
  text-shadow: 0 2px 12px rgba(0,0,0,0.6);
}
.page-about__hero-sub {
  font-size: clamp(1rem, 3vw, 1.4rem);
  color: var(--color-gold);
  font-weight: 300;
  letter-spacing: 0.08em;
  max-width: 600px;
  margin: 0 auto;
}

/* ---- 时间轴容器 ---- */
.page-about__timeline-wrap {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 3rem 1.25rem 2rem;
}
.page-about__timeline {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: var(--page-chapter-gap);
}
/* 时间轴竖线 */
.page-about__timeline::before {
  content: '';
  position: absolute;
  left: 2rem;
  top: 0.8rem;
  bottom: 0.8rem;
  width: var(--page-timeline-line-width);
  background: linear-gradient(to bottom, var(--color-gold), var(--color-deep-red));
  opacity: 0.45;
  transform: translateX(-50%);
  border-radius: 2px;
}

/* ---- 每个章节 (details) ---- */
.page-about__chapter {
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  position: relative;
  gap: 1rem;
  border-bottom: 1px solid rgba(255,215,0,0.08);
  padding-bottom: var(--page-chapter-gap);
}
.page-about__chapter[open] {
  border-bottom-color: rgba(255,215,0,0.18);
}
.page-about__chapter:last-of-type {
  border-bottom: none;
  padding-bottom: 0;
}

/* ---- 左侧节点 (summary) ---- */
.page-about__chapter-summary {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
  min-width: 4rem;
  width: 4rem;
  flex-shrink: 0;
  cursor: pointer;
  list-style: none;
  padding: 0.4rem 0;
  position: relative;
  z-index: 2;
  user-select: none;
}
.page-about__chapter-summary::-webkit-details-marker {
  display: none;
}
.page-about__chapter-summary::marker {
  display: none;
  content: '';
}
.page-about__chapter-summary:hover .page-about__node-dot {
  box-shadow: 0 0 0 6px var(--color-gold-glass);
  transform: scale(1.15);
}

.page-about__node-dot {
  display: block;
  width: var(--page-timeline-node-size);
  height: var(--page-timeline-node-size);
  border-radius: 50%;
  background: var(--color-gold);
  box-shadow: 0 0 0 3px rgba(255,215,0,0.25);
  transition: box-shadow 0.3s ease, transform 0.3s ease;
  flex-shrink: 0;
}
.page-about__node-number {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--color-gold);
  letter-spacing: 0.05em;
  line-height: 1;
}
.page-about__node-label {
  font-size: 0.65rem;
  color: var(--color-light-gray);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  writing-mode: vertical-rl;
  text-orientation: mixed;
  line-height: 1.2;
  opacity: 0.8;
}

/* ---- 右侧内容 ---- */
.page-about__chapter-content {
  flex: 1;
  min-width: 0;
  padding-top: 0.2rem;
}
.page-about__chapter-heading {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin: 0 0 0.75rem;
  font-family: var(--font-heading);
  font-size: clamp(1.4rem, 4vw, 2rem);
  color: var(--color-white);
  line-height: 1.2;
}
.page-about__rotated-note {
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--color-gold);
  writing-mode: vertical-rl;
  text-orientation: mixed;
  letter-spacing: 0.12em;
  opacity: 0.85;
  flex-shrink: 0;
  line-height: 1.1;
  transform: translateY(0.15em);
}
.page-about__heading-text {
  flex: 1;
}
.page-about__chapter-intro {
  font-size: 1rem;
  color: var(--color-light-gray);
  margin: 0 0 1rem;
  max-width: var(--page-content-max);
}
.page-about__chapter-detail {
  font-size: 0.9375rem;
  color: var(--color-light-gray);
  max-width: var(--page-content-max);
  line-height: 1.7;
}
.page-about__chapter-detail p {
  margin: 0 0 0.75rem;
}
.page-about__chapter-detail a {
  color: var(--color-gold);
  text-decoration: underline;
  text-underline-offset: 2px;
}
.page-about__chapter-detail a:hover {
  color: var(--color-white);
}

/* ---- 服务列表 (章节2) ---- */
.page-about__service-list {
  list-style: none;
  margin: 1rem 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
}
.page-about__service-item {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  padding: 0.75rem 1rem;
  background: var(--color-dark-gray);
  border-left: 3px solid var(--color-gold);
  border-radius: 0 4px 4px 0;
}
.page-about__service-label {
  font-family: var(--font-heading);
  font-size: 0.9375rem;
  color: var(--color-white);
  letter-spacing: 0.02em;
}
.page-about__service-desc {
  font-size: 0.875rem;
  color: var(--color-light-gray);
  line-height: 1.5;
}

/* ---- 章节配图 ---- */
.page-about__chapter-img {
  margin-top: 1.25rem;
  max-width: 100%;
}
.page-about__chapter-img img {
  max-width: 100%;
  height: auto;
  border-radius: 6px;
  display: block;
  box-shadow: 0 4px 20px rgba(0,0,0,0.4);
}
.page-about__chapter-img--side img {
  max-width: min(100%, 400px);
}

/* ---- 承诺徽章 ---- */
.page-about__commitment-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.25rem;
}
.page-about__badge {
  display: inline-block;
  padding: 0.35rem 1rem;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-gold);
  border: 1px solid var(--color-gold);
  border-radius: 20px;
  letter-spacing: 0.05em;
  background: rgba(255,215,0,0.06);
  transition: background 0.2s;
}
.page-about__badge:hover {
  background: var(--color-gold-glass);
}

/* ---- 底部CTA ---- */
.page-about__cta {
  max-width: var(--content-max-width);
  margin: 2rem auto 0;
  padding: 0 1.25rem;
}
.page-about__cta-inner {
  background: var(--color-dark-gray);
  border-radius: 12px;
  padding: 2.5rem 2rem;
  text-align: center;
  border: 1px solid rgba(255,215,0,0.12);
}
.page-about__cta-heading {
  font-family: var(--font-heading);
  font-size: 1.6rem;
  color: var(--color-white);
  margin: 0 0 0.5rem;
}
.page-about__cta-text {
  font-size: 1rem;
  color: var(--color-light-gray);
  max-width: 520px;
  margin: 0 auto 1.5rem;
}
.page-about__cta-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
}
.page-about__cta-btn {
  display: inline-block;
  padding: 0.7rem 1.8rem;
  font-family: var(--font-body);
  font-size: 0.9375rem;
  font-weight: 700;
  text-decoration: none;
  border-radius: 4px;
  transition: background 0.25s, color 0.25s, border-color 0.25s;
  cursor: pointer;
  background: var(--color-deep-red);
  color: var(--color-white);
  border: 2px solid var(--color-deep-red);
}
.page-about__cta-btn:hover {
  background: #a00000;
  border-color: #a00000;
  color: var(--color-white);
}
.page-about__cta-btn--secondary {
  background: var(--color-gold);
  color: var(--color-charcoal);
  border-color: var(--color-gold);
}
.page-about__cta-btn--secondary:hover {
  background: #e6c200;
  border-color: #e6c200;
  color: var(--color-charcoal);
}
.page-about__cta-btn--outline {
  background: transparent;
  color: var(--color-gold);
  border-color: var(--color-gold);
}
.page-about__cta-btn--outline:hover {
  background: var(--color-gold-glass);
  color: var(--color-white);
  border-color: var(--color-gold);
}

/* ===== 移动端优先 (核心样式已为窄屏设计) ===== */

/* 中等屏幕以上：布局强化 */
@media (min-width: 640px) {
  .page-about__timeline-wrap {
    padding: 3.5rem 2rem 2rem;
  }
  .page-about__timeline::before {
    left: 2.8rem;
  }
  .page-about__chapter-summary {
    min-width: 5rem;
    width: 5rem;
    gap: 0.4rem;
  }
  .page-about__node-dot {
    width: 1.1rem;
    height: 1.1rem;
  }
  .page-about__node-label {
    font-size: 0.7rem;
  }
  .page-about__service-list {
    grid-template-columns: 1fr 1fr;
  }
  .page-about__cta-inner {
    padding: 3rem 2.5rem;
  }
}

@media (min-width: 900px) {
  .page-about__timeline-wrap {
    padding: 4rem 2.5rem 2rem;
  }
  .page-about__timeline::before {
    left: 3.2rem;
  }
  .page-about__chapter-summary {
    min-width: 6rem;
    width: 6rem;
    padding: 0.6rem 0;
  }
  .page-about__node-dot {
    width: 1.25rem;
    height: 1.25rem;
  }
  .page-about__node-number {
    font-size: 0.85rem;
  }
  .page-about__node-label {
    font-size: 0.75rem;
  }
  .page-about__chapter-heading {
    font-size: clamp(1.6rem, 3vw, 2.25rem);
  }
  .page-about__rotated-note {
    font-size: 0.8rem;
  }
  .page-about__chapter-content {
    padding-top: 0.4rem;
  }
  .page-about__chapter-img--side {
    max-width: 70%;
  }
  .page-about__service-list {
    grid-template-columns: 1fr 1fr;
  }
  .page-about__commitment-badges {
    gap: 1rem;
  }
  .page-about__cta-heading {
    font-size: 1.8rem;
  }
}

/* 大屏：时间轴节点更舒展 */
@media (min-width: 1200px) {
  .page-about__timeline::before {
    left: 3.6rem;
  }
  .page-about__chapter-summary {
    min-width: 7rem;
    width: 7rem;
  }
  .page-about__node-dot {
    width: 1.4rem;
    height: 1.4rem;
  }
  .page-about__chapter {
    gap: 1.5rem;
  }
}

/* 确保details open/close 动画平滑 */
.page-about__chapter .page-about__chapter-content {
  overflow: hidden;
  transition: opacity 0.3s ease, max-height 0.4s ease;
}
.page-about__chapter:not([open]) .page-about__chapter-content {
  opacity: 0;
  max-height: 0;
  padding-top: 0;
  padding-bottom: 0;
  margin-top: 0;
  margin-bottom: 0;
  pointer-events: none;
}
.page-about__chapter[open] .page-about__chapter-content {
  opacity: 1;
  max-height: 1200px;
}

/* 图片响应式兜底 */
.page-about img {
  max-width: 100%;
  height: auto;
}

/* 减少大屏下hero高度 */
@media (min-width: 800px) {
  .page-about__hero {
    min-height: 400px;
    max-height: 60vh;
  }
}
/* 确保焦点可见 */
.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--color-gold);
  outline-offset: 4px;
}