/* ===== 页面专属：品牌档案 ===== */
.page-about {
  --axis-line: var(--c-gold);
  --axis-width: 2px;
  --index-ring: var(--c-gold);
  --panel-brand-bg: linear-gradient(135deg, var(--c-teal-dark) 0%, var(--c-tech-blue) 100%);
  --panel-philosophy-bg: linear-gradient(225deg, var(--c-tech-blue) 0%, var(--c-teal-dark) 100%);
  --panel-services-bg: linear-gradient(160deg, var(--c-teal-dark) 0%, var(--c-tech-blue-light) 100%);
  --panel-cta-bg: var(--c-tech-blue);
  --panel-radius: 0;
  --content-gap: var(--space-lg);
  --figure-radius: 4px;
  position: relative;
}

/* 面包屑 */
.page-about .breadcrumb {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-md) var(--space-lg) 0;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.03em;
  color: var(--c-gold);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}
.page-about .breadcrumb a {
  color: var(--c-gold);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s;
}
.page-about .breadcrumb a:hover {
  border-color: var(--c-gold);
}
.page-about .breadcrumb__sep {
  opacity: 0.5;
}
.page-about .breadcrumb__current {
  color: var(--c-off-white);
  opacity: 0.8;
}

/* 首屏框景 */
.page-about .hero-frame {
  position: relative;
  margin: 0 var(--space-md) var(--space-xl);
  border: 3px solid var(--c-gold);
  outline: 1px solid var(--c-border);
  outline-offset: -8px;
  background: linear-gradient(145deg, rgba(29,53,87,0.95) 0%, rgba(42,157,143,0.6) 100%);
  overflow: hidden;
}
.page-about .hero-frame::before,
.page-about .hero-frame::after {
  content: "";
  position: absolute;
  width: 20px;
  height: 20px;
  border-color: var(--c-gold);
  border-style: solid;
  z-index: 2;
  pointer-events: none;
}
.page-about .hero-frame::before {
  top: -1px;
  left: -1px;
  border-width: 3px 0 0 3px;
}
.page-about .hero-frame::after {
  bottom: -1px;
  right: -1px;
  border-width: 0 3px 3px 0;
}
.page-about .hero-frame__inner {
  position: relative;
  padding: var(--space-xl) var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  z-index: 1;
}
.page-about .hero-frame__title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 2.2rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--c-off-white);
  margin: 0;
  line-height: 1.15;
}
.page-about .hero-frame__desc {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--c-off-white);
  opacity: 0.9;
  max-width: 42em;
  margin: 0;
}
.page-about .hero-frame__img {
  width: 100%;
  max-width: 400px;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: var(--figure-radius);
  border: 1px solid rgba(244,162,97,0.3);
  align-self: center;
}
.page-about .hero-frame__scale {
  display: flex;
  justify-content: space-between;
  padding: 0 var(--space-sm);
  margin-top: var(--space-sm);
}
.page-about .hero-frame__scale-mark {
  display: block;
  width: 1px;
  height: 12px;
  background: var(--c-gold);
  opacity: 0.4;
}
.page-about .hero-frame__scale-mark:nth-child(1) { opacity: 0.8; }
.page-about .hero-frame__scale-mark:nth-child(5) { opacity: 0.8; }

/* 堆叠面板通用 */
.page-about .stack-panel {
  position: relative;
  padding: var(--space-xl) 0;
  margin-bottom: var(--space-lg);
  background: var(--panel-brand-bg);
  border-radius: var(--panel-radius);
  box-shadow: var(--shadow-panel);
  overflow: hidden;
}
.page-about .stack-panel--alt {
  background: var(--panel-philosophy-bg);
}
.page-about .stack-panel--services {
  background: var(--panel-services-bg);
}
.page-about .stack-panel--cta {
  background: var(--panel-cta-bg);
}

/* 坐标轴线 —— 左侧贯穿 */
.page-about .stack-panel__axis {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 28px;
  width: var(--axis-width);
  background: var(--axis-line);
  opacity: 0.25;
  pointer-events: none;
  z-index: 0;
}
@media (min-width: 768px) {
  .page-about .stack-panel__axis {
    left: 52px;
    opacity: 0.3;
  }
}

/* 面板内部网格 */
.page-about .stack-panel__grid {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  gap: var(--content-gap);
  padding-left: 56px;
}
@media (min-width: 768px) {
  .page-about .stack-panel__grid {
    display: grid;
    grid-template-columns: 80px 1fr 1fr;
    gap: var(--space-xl);
    padding-left: 80px;
    align-items: start;
  }
  .page-about .stack-panel__grid--reverse {
    grid-template-columns: 80px 1fr 1fr;
    direction: rtl;
  }
  .page-about .stack-panel__grid--reverse > * {
    direction: ltr;
  }
}
@media (min-width: 1024px) {
  .page-about .stack-panel__grid {
    grid-template-columns: 100px 1.1fr 0.9fr;
    padding-left: 100px;
  }
  .page-about .stack-panel__grid--reverse {
    grid-template-columns: 100px 0.9fr 1.1fr;
  }
}

/* 索引标签 */
.page-about .index-tag {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 600;
  color: var(--c-gold);
  background: rgba(0,0,0,0.2);
  padding: var(--space-xs) var(--space-sm);
  border-left: 3px solid var(--c-gold);
  line-height: 1;
  display: inline-block;
  width: -moz-fit-content;
  width: fit-content;
  animation: index-scale linear;
  animation-timeline: view();
  animation-range: entry 0% entry 100%;
  transform-origin: left center;
}
@keyframes index-scale {
  0% { transform: scale(0.7); opacity: 0.4; background: rgba(0,0,0,0.05); }
  100% { transform: scale(1); opacity: 1; background: rgba(0,0,0,0.25); }
}
@media (min-width: 768px) {
  .page-about .index-tag {
    font-size: 2.2rem;
    padding: var(--space-sm) var(--space-md);
  }
}
@media (min-width: 1024px) {
  .page-about .index-tag {
    font-size: 2.8rem;
  }
}

/* 面板内容 */
.page-about .stack-panel__content {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}
.page-about .stack-panel__heading {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.6rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--c-off-white);
  margin: 0;
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid rgba(244,162,97,0.3);
}
.page-about .stack-panel__text {
  font-family: var(--font-body);
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--c-off-white);
  opacity: 0.88;
  margin: 0;
}
.page-about .stack-panel__figure {
  margin: 0;
  align-self: center;
}
.page-about .stack-panel__img {
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: attr(width) / attr(height);
  object-fit: cover;
  border-radius: var(--figure-radius);
  border: 1px solid rgba(244,162,97,0.2);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
  transition: transform 0.3s ease;
}
.page-about .stack-panel__img:hover {
  transform: scale(1.01);
}
@media (min-width: 768px) {
  .page-about .stack-panel__heading {
    font-size: 1.8rem;
  }
  .page-about .stack-panel__text {
    font-size: 1rem;
  }
}

/* details 展开组件 */
.page-about .panel-details {
  margin-top: var(--space-sm);
  border-left: 3px solid var(--c-gold);
  padding-left: var(--space-md);
}
.page-about .panel-details__summary {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--c-gold);
  cursor: pointer;
  list-style: none;
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  transition: color 0.2s;
  user-select: none;
}
.page-about .panel-details__summary::-webkit-details-marker {
  display: none;
}
.page-about .panel-details__summary::before {
  content: "▶";
  font-size: 0.7rem;
  transition: transform 0.25s;
}
.page-about .panel-details[open] .panel-details__summary::before {
  transform: rotate(90deg);
}
.page-about .panel-details__summary:hover {
  color: var(--c-gold-light);
}
.page-about .panel-details__body {
  padding-top: var(--space-sm);
  animation: details-fade 0.3s ease-out;
}
@keyframes details-fade {
  0% { opacity: 0; transform: translateY(-6px); }
  100% { opacity: 1; transform: translateY(0); }
}
.page-about .panel-details__body p {
  font-family: var(--font-body);
  font-size: 0.9rem;
  line-height: 1.6;
  color: var(--c-off-white);
  opacity: 0.82;
  margin: 0 0 var(--space-sm);
}
.page-about .panel-details__body p:last-child {
  margin-bottom: 0;
}

/* 服务范围卡片网格 */
.page-about .service-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
}
@media (min-width: 560px) {
  .page-about .service-grid {
    grid-template-columns: 1fr 1fr;
  }
}
@media (min-width: 768px) {
  .page-about .service-grid {
    gap: var(--space-lg);
  }
}
.page-about .service-card {
  background: rgba(0,0,0,0.15);
  padding: var(--space-md);
  border-radius: var(--radius);
  border-left: 4px solid var(--c-gold);
  transition: background 0.25s, transform 0.2s;
}
.page-about .service-card:hover {
  background: rgba(0,0,0,0.25);
  transform: translateX(4px);
}
.page-about .service-card__icon {
  display: block;
  width: 28px;
  height: 28px;
  margin-bottom: var(--space-sm);
  background: var(--c-gold);
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='22 12 18 12 15 21 9 3 6 12 2 12'%3E%3C/polyline%3E%3C/svg%3E") center/contain no-repeat;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='22 12 18 12 15 21 9 3 6 12 2 12'%3E%3C/polyline%3E%3C/svg%3E") center/contain no-repeat;
  -webkit-mask-repeat: no-repeat;
  mask-repeat: no-repeat;
}
.page-about .service-card__title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--c-off-white);
  margin: 0 0 var(--space-xs);
}
.page-about .service-card__desc {
  font-family: var(--font-body);
  font-size: 0.9rem;
  line-height: 1.5;
  color: var(--c-off-white);
  opacity: 0.8;
  margin: 0;
}

/* 内部导航 */
.page-about .internal-nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  margin-top: var(--space-sm);
}
.page-about .internal-nav .btn {
  font-family: var(--font-body);
  font-size: 0.95rem;
  padding: var(--space-sm) var(--space-lg);
  border-radius: var(--radius);
  text-decoration: none;
  transition: background 0.25s, color 0.25s, border-color 0.25s;
  border: 2px solid transparent;
}
.page-about .internal-nav .btn--primary {
  background: var(--c-primary);
  color: var(--c-off-white);
  border-color: var(--c-primary);
}
.page-about .internal-nav .btn--primary:hover {
  background: var(--c-primary-hover);
  border-color: var(--c-primary-hover);
}
.page-about .internal-nav .btn--ghost {
  background: transparent;
  color: var(--c-off-white);
  border-color: rgba(244,162,97,0.4);
}
.page-about .internal-nav .btn--ghost:hover {
  background: rgba(244,162,97,0.12);
  border-color: var(--c-gold);
}

/* 响应式微调 */
@media (max-width: 359px) {
  .page-about .hero-frame__title {
    font-size: 1.6rem;
  }
  .page-about .stack-panel__grid {
    padding-left: 40px;
  }
  .page-about .stack-panel__axis {
    left: 18px;
  }
  .page-about .index-tag {
    font-size: 1.2rem;
  }
}
@media (min-width: 768px) {
  .page-about .hero-frame {
    margin: 0 var(--space-xl) var(--space-2xl);
  }
  .page-about .hero-frame__inner {
    padding: var(--space-2xl) var(--space-xl);
    display: grid;
    grid-template-columns: 1fr 360px;
    grid-template-rows: auto auto auto auto;
    gap: var(--space-md) var(--space-xl);
    align-items: start;
  }
  .page-about .hero-frame .index-tag {
    grid-column: 1 / 2;
    grid-row: 1 / 2;
  }
  .page-about .hero-frame__title {
    grid-column: 1 / 2;
    grid-row: 2 / 3;
    font-size: 2.8rem;
  }
  .page-about .hero-frame__desc {
    grid-column: 1 / 2;
    grid-row: 3 / 4;
  }
  .page-about .hero-frame__img {
    grid-column: 2 / 3;
    grid-row: 1 / 4;
    max-width: 100%;
    align-self: center;
  }
  .page-about .hero-frame__scale {
    grid-column: 1 / 3;
    grid-row: 4 / 5;
  }
}
@media (min-width: 1024px) {
  .page-about .hero-frame__inner {
    grid-template-columns: 1fr 440px;
  }
  .page-about .hero-frame__title {
    font-size: 3.4rem;
  }
  .page-about .stack-panel {
    padding: var(--space-2xl) 0;
  }
}

/* 容器复用 */
.page-about .container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}
@media (max-width: 359px) {
  .page-about .container {
    padding: 0 var(--space-md);
  }
}

/* 确保图片不溢出 */
.page-about img {
  max-width: 100%;
  height: auto;
}

/* 打印优化 */
@media print {
  .page-about .hero-frame {
    border-color: #ccc;
    outline-color: #ccc;
  }
  .page-about .stack-panel {
    break-inside: avoid;
    background: #f5f5f5 !important;
    color: #333;
  }
  .page-about .stack-panel__heading,
  .page-about .stack-panel__text,
  .page-about .index-tag,
  .page-about .service-card__title,
  .page-about .service-card__desc {
    color: #333 !important;
  }
  .page-about .internal-nav .btn {
    border-color: #999;
    color: #333;
  }
}