.page-about {
  display: block;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: var(--section-y) 0 var(--space-6);
  background:
    radial-gradient(130% 120% at 86% -12%, color-mix(in srgb, var(--color-accent) 58%, transparent), transparent 58%),
    linear-gradient(198deg,
      color-mix(in srgb, var(--color-primary) 82%, var(--color-contrast-surface)) 0%,
      var(--color-primary) 62%,
      color-mix(in srgb, var(--color-primary) 86%, var(--color-accent)) 100%);
  color: var(--color-primary-ink);
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero .breadcrumb,
.page-about .about-hero .breadcrumb a {
  color: color-mix(in srgb, var(--color-primary-ink) 76%, transparent);
}

.page-about .about-hero .breadcrumb a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-hero .breadcrumb a:hover {
  color: var(--color-primary-ink);
}

.page-about .about-hero__eyebrow {
  margin: var(--space-4) 0 var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  color: color-mix(in srgb, var(--color-primary-ink) 70%, transparent);
}

.page-about .about-hero h1 {
  margin: 0 0 var(--space-3);
  max-width: 22ch;
  font-family: var(--font-heading);
  font-size: var(--text-3xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-primary-ink);
}

.page-about .about-hero__lede {
  max-width: var(--measure);
  margin: 0;
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: color-mix(in srgb, var(--color-primary-ink) 84%, transparent);
}

.page-about .about-hero__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
  margin: var(--space-4) 0 0;
  padding-top: var(--space-2);
  border-top: var(--border-thin) solid color-mix(in srgb, var(--color-primary-ink) 26%, transparent);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: color-mix(in srgb, var(--color-primary-ink) 78%, transparent);
}

.page-about .about-hero__meta .sep {
  opacity: 0.55;
}

/* ---------- 目录条 ---------- */

.page-about .about-index {
  background: var(--color-surface-deep);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-about .about-index__list {
  display: flex;
  gap: var(--space-1);
  margin: 0;
  padding: var(--space-2) 0;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-index__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 6px var(--space-2);
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-pill);
  white-space: nowrap;
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  text-decoration: none;
  transition: background-color 200ms ease, color 200ms ease, border-color 200ms ease;
}

.page-about .about-index__link .num {
  font-size: var(--text-xs);
  color: var(--color-accent);
}

.page-about .about-index__link:hover,
.page-about .about-index__link.is-active {
  background: var(--color-primary-soft);
  border-color: var(--color-focus);
  color: var(--color-ink);
}

/* ---------- 章节容器 ---------- */

.page-about .about-section {
  padding: var(--section-y) 0;
  background: var(--color-surface);
}

.page-about .about-section--alt {
  background: var(--color-surface-alt);
}

.page-about .about-section--deep {
  background: var(--color-surface-deep);
}

.page-about .about-section--night {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

/* ---------- 纵向时间轴 ---------- */

.page-about .about-track {
  position: relative;
  display: grid;
  gap: var(--space-6);
}

.page-about .about-track::before {
  content: "";
  position: absolute;
  top: 8px;
  bottom: 8px;
  left: 15px;
  width: var(--border-thin);
  background: linear-gradient(180deg,
    var(--color-accent) 0%,
    var(--color-line) 16%,
    var(--color-line) 84%,
    transparent 100%);
}

.page-about .about-node {
  position: relative;
  padding-left: 46px;
}

.page-about .about-node__num {
  position: absolute;
  left: 0;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 31px;
  height: 31px;
  border: var(--border-thin) solid var(--color-accent);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-variant-numeric: tabular-nums;
}

.page-about .about-node__body {
  min-width: 0;
}

.page-about .about-node__kicker {
  margin: 0 0 var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  color: var(--color-accent);
}

.page-about .about-node__title {
  margin: 0 0 var(--space-3);
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

.page-about .about-node__body > p {
  max-width: var(--measure);
  margin: 0 0 var(--space-3);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink);
}

.page-about .about-node__body > p:last-child {
  margin-bottom: 0;
}

/* 深色章节内的文字反相 */

.page-about .about-section--night .about-node__title,
.page-about .about-section--night .about-node__body > p {
  color: var(--color-contrast-ink);
}

.page-about .about-section--night .about-node__kicker {
  color: var(--color-contrast-accent);
}

.page-about .about-section--night .about-track::before {
  background: linear-gradient(180deg,
    var(--color-contrast-accent) 0%,
    var(--color-contrast-line) 16%,
    var(--color-contrast-line) 84%,
    transparent 100%);
}

.page-about .about-section--night .about-node__num {
  background: var(--color-contrast-surface);
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
}

/* ---------- 左侧色条强调段 ---------- */

.page-about .about-quote {
  margin: var(--space-4) 0 0;
  padding: var(--space-2) var(--space-3);
  border-left: 3px solid var(--color-accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: linear-gradient(90deg,
    color-mix(in srgb, var(--color-accent) 10%, transparent) 0%,
    transparent 72%);
}

.page-about .about-quote p {
  margin: 0;
  max-width: 62ch;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-about .about-section--night .about-quote {
  border-left-color: var(--color-contrast-accent);
  background: linear-gradient(90deg,
    color-mix(in srgb, var(--color-contrast-accent) 16%, transparent) 0%,
    transparent 72%);
}

.page-about .about-section--night .about-quote p {
  color: var(--color-contrast-ink);
}

/* ---------- 图片与展签 ---------- */

.page-about .about-media {
  position: relative;
  margin: var(--space-6) 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--color-surface-deep);
  box-shadow: var(--shadow-1);
}

.page-about .about-media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-about .about-media .media-caption {
  position: absolute;
  left: var(--space-2);
  bottom: var(--space-2);
  margin: 0;
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  background: color-mix(in srgb, var(--color-highlight) 90%, transparent);
  color: var(--color-ink);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
}

/* ---------- 两条业务线 ---------- */

.page-about .about-lines {
  display: grid;
  gap: var(--space-3);
  margin: var(--space-4) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-lines__item {
  padding: var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  border-left: 3px solid var(--color-accent);
  border-radius: var(--radius-md);
  background: color-mix(in srgb, var(--color-surface) 74%, transparent);
  box-shadow: var(--shadow-1);
  backdrop-filter: blur(8px);
  transition: transform 220ms ease, border-color 220ms ease;
}

.page-about .about-lines__item:hover {
  transform: translateY(-2px);
  border-color: color-mix(in srgb, var(--color-accent) 45%, var(--color-line));
}

.page-about .about-lines__item h3 {
  margin: 0 0 var(--space-1);
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  color: var(--color-ink);
}

.page-about .about-lines__item p {
  margin: 0 0 var(--space-2);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-about .about-lines__link {
  display: inline-block;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-accent);
  text-decoration: none;
  border-bottom: var(--border-thin) solid color-mix(in srgb, var(--color-accent) 40%, transparent);
  padding-bottom: 2px;
}

.page-about .about-lines__link:hover {
  color: var(--color-focus);
  border-bottom-color: var(--color-focus);
}

/* ---------- 区域刻度列表 ---------- */

.page-about .about-regions {
  margin: var(--space-6) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-regions__item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: var(--space-2);
  align-items: baseline;
  padding: var(--space-2) 0;
  border-top: var(--border-thin) solid var(--color-line);
}

.page-about .about-regions__item:last-child {
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-about .about-regions__num {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-variant-numeric: tabular-nums;
  color: var(--color-accent);
}

.page-about .about-regions__name {
  margin: 0 0 2px;
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--color-ink);
}

.page-about .about-regions__desc {
  margin: 0;
  max-width: 62ch;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* ---------- 当季数字 ---------- */

.page-about .about-progress {
  display: grid;
  gap: var(--space-3);
  margin: var(--space-4) 0 0;
  padding: 0;
}

.page-about .about-progress__row {
  padding: var(--space-3);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-line) 86%, transparent);
  border-radius: var(--radius-md);
  background: color-mix(in srgb, var(--color-surface) 70%, transparent);
  box-shadow: var(--shadow-1);
  backdrop-filter: blur(8px);
}

.page-about .about-progress__num {
  display: block;
  margin: 0 0 var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-3xl);
  font-variant-numeric: tabular-nums;
  line-height: 1;
  color: var(--color-primary);
}

.page-about .about-progress__desc {
  margin: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* ---------- 收束出口 ---------- */

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2) var(--space-3);
  margin-top: var(--space-4);
  padding-top: var(--space-3);
  border-top: var(--border-thin) solid var(--color-contrast-line);
}

.page-about .about-link {
  font-size: var(--text-sm);
  color: var(--color-contrast-accent);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: var(--border-thin) solid color-mix(in srgb, var(--color-contrast-accent) 45%, transparent);
  transition: color 180ms ease, border-color 180ms ease;
}

.page-about .about-link:hover {
  color: var(--color-contrast-ink);
  border-bottom-color: var(--color-contrast-ink);
}

/* ---------- 焦点态 ---------- */

.page-about a:focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

.page-about .about-section--night a:focus-visible {
  outline-color: var(--color-contrast-accent);
}

/* ---------- 响应式 ---------- */

@media (min-width: 700px) {
  .page-about .about-progress {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-4);
  }

  .page-about .about-regions__item {
    grid-template-columns: 56px minmax(0, 1fr);
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: var(--section-y-lg) 0 var(--space-8);
  }

  .page-about .about-hero h1 {
    font-size: var(--text-4xl);
    max-width: 24ch;
  }

  .page-about .about-hero__lede {
    font-size: var(--text-lg);
  }

  .page-about .about-index__list {
    gap: var(--space-2);
    padding: var(--space-2) 0;
  }

  .page-about .about-track::before {
    left: 27px;
  }

  .page-about .about-node {
    padding-left: 92px;
  }

  .page-about .about-node__num {
    width: 55px;
    height: 55px;
    font-size: var(--text-sm);
  }

  .page-about .about-node__title {
    font-size: var(--text-3xl);
  }

  .page-about .about-lines {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-media {
    margin-top: var(--space-8);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-lines__item,
  .page-about .about-lines__link,
  .page-about .about-link,
  .page-about .about-index__link {
    transition: none;
  }

  .page-about .about-lines__item:hover {
    transform: none;
  }
}