.page-about {
  --about-hero-grid: linear-gradient(rgba(0, 229, 255, .05) 1px, transparent 1px), linear-gradient(90deg, rgba(0, 229, 255, .05) 1px, transparent 1px);
  --about-hero-glow: radial-gradient(circle at 82% 18%, rgba(0, 229, 255, .2), transparent 44%), radial-gradient(circle at 12% 88%, rgba(180, 255, 58, .14), transparent 52%);
  --about-card-cyber: linear-gradient(145deg, rgba(0, 229, 255, .1), rgba(180, 255, 58, .05));
  --about-card-accent: linear-gradient(135deg, rgba(180, 255, 58, .2), rgba(0, 229, 255, .09)), var(--paper-light);
  overflow-x: clip;
}

.page-about .about-wrap {
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--page-gutter);
}

.page-about .about-wrap--narrow {
  max-width: 960px;
}

.page-about .section {
  padding-block: 56px;
  position: relative;
}

@media (min-width: 768px) {
  .page-about .section {
    padding-block: 92px;
  }
}

/* 通用章节头 */
.page-about .section-caption {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 8px 14px;
  align-items: start;
  margin-bottom: 28px;
  position: relative;
}

.page-about .section-caption .mono {
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--ink-soft);
  text-transform: uppercase;
}

.page-about .section-caption h2 {
  font-family: var(--font-head);
  font-size: clamp(26px, 4vw, 38px);
  line-height: 1.18;
  margin: 4px 0 0;
  color: var(--ink);
}

.page-about .section-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  padding: 10px 0;
  border-radius: var(--radius-pill);
  background: var(--paper-warm);
  color: var(--ink-soft);
  font-size: 14px;
  font-weight: 700;
}

.page-about .section-index--dark {
  background: var(--ink);
  color: var(--neon);
}

.page-about .section-caption .note-vertical {
  position: absolute;
  top: 4px;
  right: 0;
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  padding: 12px 8px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(0, 229, 255, .35);
  background: rgba(0, 229, 255, .08);
  color: var(--ink-soft);
}

/* 全局悬停胶囊 */
.page-about .tag {
  transition: transform .25s var(--ease), box-shadow .25s var(--ease), background-color .25s var(--ease);
}

.page-about .tag:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, .1);
}

.page-about .tag--neon {
  background: var(--neon);
  color: var(--ink);
}

.page-about .tag--cyber {
  background: var(--cyber);
  color: var(--ink);
}

/* ===== Hero ===== */
.page-about .about-hero {
  position: relative;
  background: var(--about-hero-grid), var(--about-hero-glow), var(--ink);
  background-size: 44px 44px, 44px 44px, auto, auto, auto;
  color: var(--paper);
  padding: 28px 0 52px;
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -90px;
  bottom: -70px;
  width: 280px;
  height: 280px;
  border: 1px solid rgba(0, 229, 255, .3);
  border-radius: 50%;
  pointer-events: none;
}

.page-about .about-hero__inner {
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--page-gutter);
  position: relative;
  z-index: 1;
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: 20px;
}

.page-about .about-hero .breadcrumbs a {
  color: rgba(244, 233, 216, .72);
  transition: color .2s var(--ease);
}

.page-about .about-hero .breadcrumbs a:hover {
  color: var(--neon);
}

.page-about .about-hero .breadcrumbs [aria-current="page"] {
  color: var(--neon);
}

.page-about .about-hero__kicker {
  font-size: 12px;
  letter-spacing: .22em;
  color: var(--neon);
  margin: 0 0 16px;
}

.page-about .about-hero h1 {
  font-family: var(--font-head);
  font-size: clamp(32px, 7vw, 56px);
  font-weight: 700;
  line-height: 1.14;
  letter-spacing: -.02em;
  margin: 0 0 18px;
  max-width: 12em;
  color: var(--paper);
}

.page-about .about-hero .lead {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.85;
  color: rgba(244, 233, 216, .84);
  max-width: 58ch;
  margin: 0;
}

.page-about .about-hero__grid {
  display: grid;
  gap: 28px;
  margin-top: 28px;
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: 1.5fr 1fr;
    align-items: end;
    gap: 44px;
    margin-top: 40px;
  }
}

.page-about .about-hero__aside {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

@media (min-width: 768px) and (max-width: 899px) {
  .page-about .about-hero__aside {
    grid-template-columns: repeat(3, 160px);
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__aside {
    grid-template-columns: 1fr;
    gap: 14px;
  }
}

.page-about .about-hero__stat {
  background: rgba(0, 229, 255, .08);
  border: 1px solid rgba(0, 229, 255, .3);
  border-radius: var(--radius-md);
  padding: 16px 18px;
}

.page-about .about-hero__stat-num {
  display: block;
  font-family: var(--font-head);
  font-size: 40px;
  font-weight: 700;
  line-height: 1;
  color: var(--cyber);
  margin-bottom: 8px;
}

.page-about .about-hero__stat-label {
  font-family: var(--font-body);
  font-size: 13px;
  color: rgba(244, 233, 216, .76);
}

/* ===== 品牌起点 ===== */
.page-about .about-origin {
  background: var(--paper);
}

.page-about .about-origin__grid {
  display: grid;
  gap: 32px;
  margin-top: 32px;
}

@media (min-width: 768px) {
  .page-about .about-origin__grid {
    grid-template-columns: 1.2fr 1fr;
    gap: 52px;
    margin-top: 44px;
  }
}

.page-about .about-origin__copy p {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.95;
  color: var(--ink);
  margin: 0 0 18px;
}

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

.page-about .about-origin__aside {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.page-about .about-origin__year {
  font-family: var(--font-mono);
  font-size: clamp(40px, 6vw, 64px);
  font-weight: 700;
  line-height: .94;
  color: var(--ink);
  background: var(--paper-warm);
  border-radius: var(--radius-lg);
  padding: 24px 28px;
  display: inline-block;
  align-self: flex-start;
}

.page-about .about-origin__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-origin__cards {
  display: grid;
  gap: 14px;
}

.page-about .about-origin__card {
  background: var(--paper-light);
  border: 1px solid rgba(58, 58, 58, .14);
  border-radius: var(--radius-lg);
  padding: 20px 22px;
}

.page-about .about-origin__card h3 {
  font-family: var(--font-head);
  font-size: 16px;
  margin: 0 0 8px;
}

.page-about .about-origin__card p {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
  margin: 0;
}

/* ===== 时间线 ===== */
.page-about .about-timeline {
  background: var(--paper-light);
  overflow: hidden;
}

.page-about .about-timeline__header {
  margin-bottom: 28px;
}

.page-about .about-timeline__wrap {
  position: relative;
  margin-top: 40px;
}

.page-about .about-timeline__line {
  position: absolute;
  left: 22px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--neon), var(--cyber), var(--gold));
  opacity: .85;
}

.page-about .timeline-item {
  position: relative;
  padding-left: 56px;
  margin-bottom: 30px;
}

.page-about .timeline-item:last-child {
  margin-bottom: 0;
}

.page-about .timeline-item__marker {
  position: absolute;
  left: 22px;
  top: 4px;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  z-index: 2;
}

.page-about .timeline-item__year {
  font-size: 13px;
  font-weight: 700;
  color: var(--neon);
  background: var(--ink);
  padding: 6px 10px;
  border-radius: var(--radius-pill);
  white-space: nowrap;
}

.page-about .timeline-item__version {
  font-family: var(--font-head);
  font-size: 12px;
  font-weight: 700;
  background: var(--cyber);
  color: var(--ink);
  padding: 3px 8px;
  border-radius: var(--radius-pill);
  white-space: nowrap;
}

.page-about .timeline-item--current .timeline-item__year {
  background: var(--neon);
  color: var(--ink);
}

.page-about .timeline-item__content {
  box-shadow: var(--shadow-card);
}

.page-about .timeline-item__content h3 {
  font-family: var(--font-head);
  font-size: 20px;
  margin: 0 0 8px;
  color: var(--ink);
}

.page-about .timeline-item__content p {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink);
  margin: 0;
}

.page-about .timeline-item__content--current {
  border: 1px solid rgba(0, 229, 255, .45);
  box-shadow: 0 0 0 4px rgba(0, 229, 255, .08), var(--shadow-card);
}

.page-about .timeline-item__details {
  margin-top: 14px;
}

.page-about .timeline-item__details summary {
  display: inline-block;
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ink-soft);
  padding: 6px 14px;
  border: 1px solid var(--gray-line);
  border-radius: var(--radius-pill);
  transition: background-color .25s var(--ease), border-color .25s var(--ease), color .25s var(--ease);
}

.page-about .timeline-item__details summary:hover {
  background: var(--neon);
  border-color: var(--neon);
  color: var(--ink);
}

.page-about .timeline-item__details[open] summary {
  background: var(--neon);
  border-color: var(--neon);
  color: var(--ink);
}

.page-about .timeline-item__details ul {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
}

.page-about .timeline-item__details li {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.6;
  padding: 8px 0;
  border-bottom: 1px solid rgba(58, 58, 58, .12);
}

.page-about .timeline-item__details li:last-child {
  border-bottom: none;
}

@media (min-width: 900px) {
  .page-about .about-timeline__line {
    left: 50%;
  }

  .page-about .timeline-item {
    width: 50%;
    padding-left: 0;
    padding-right: 56px;
    margin-left: 0;
    margin-right: auto;
  }

  .page-about .timeline-item:nth-of-type(even) {
    margin-left: auto;
    margin-right: 0;
    padding-left: 56px;
    padding-right: 0;
  }

  .page-about .timeline-item__marker {
    left: auto;
    right: -1px;
    transform: translateX(50%);
  }

  .page-about .timeline-item:nth-of-type(even) .timeline-item__marker {
    left: -1px;
    right: auto;
    transform: translateX(-50%);
  }
}

/* ===== 导航变更 ===== */
.page-about .about-navshift {
  background: var(--paper);
}

.page-about .about-navshift__lead {
  margin-top: 24px;
  margin-bottom: 32px;
}

.page-about .about-navshift__compare {
  display: grid;
  gap: 16px;
  position: relative;
}

@media (min-width: 900px) {
  .page-about .about-navshift__compare {
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    gap: 24px;
  }
}

.page-about .about-navshift__col {
  padding: 24px;
  border: 1px solid rgba(58, 58, 58, .14);
}

.page-about .about-navshift__col--new {
  border: 2px solid rgba(180, 255, 58, .65);
  box-shadow: 0 0 0 4px rgba(180, 255, 58, .08), var(--shadow-card);
}

.page-about .about-navshift__col-head {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

.page-about .about-navshift__path {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-navshift__path li {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 0;
  border-bottom: 1px dashed rgba(58, 58, 58, .18);
  font-family: var(--font-body);
  font-size: 15px;
  color: var(--ink);
}

.page-about .about-navshift__path li:last-child {
  border-bottom: none;
}

.page-about .about-navshift__path .mono {
  font-size: 12px;
  color: var(--ink-soft);
}

.page-about .about-navshift__arrow {
  font-size: 38px;
  line-height: 1;
  text-align: center;
  color: var(--neon);
  font-family: var(--font-head);
  font-weight: 700;
}

@media (max-width: 899px) {
  .page-about .about-navshift__arrow {
    transform: rotate(90deg);
    font-size: 30px;
  }
}

.page-about .about-navshift__notes {
  display: grid;
  gap: 24px;
  margin-top: 40px;
}

@media (min-width: 768px) {
  .page-about .about-navshift__notes {
    grid-template-columns: 1fr 1fr;
    gap: 44px;
  }
}

.page-about .about-navshift__note h3 {
  font-family: var(--font-head);
  font-size: 18px;
  margin: 0 0 10px;
  color: var(--ink);
}

.page-about .about-navshift__note p {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.9;
  color: var(--ink);
  margin: 0;
}

/* ===== 内容中心 ===== */
.page-about .about-contenthub {
  background: var(--ink);
  color: var(--paper);
}

.page-about .about-contenthub .section-caption h2 {
  color: var(--paper);
}

.page-about .about-contenthub .section-caption .mono {
  color: var(--cyber);
}

.page-about .about-contenthub .section-caption .note-vertical {
  color: var(--neon);
  border-color: rgba(180, 255, 58, .4);
  background: rgba(180, 255, 58, .08);
}

.page-about .about-contenthub .lead {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  color: rgba(244, 233, 216, .82);
  margin: 0 0 28px;
}

.page-about .about-contenthub__grid {
  display: grid;
  gap: 14px;
}

@media (min-width: 640px) {
  .page-about .about-contenthub__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .page-about .about-contenthub__grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.page-about .about-contenthub__item {
  background: rgba(255, 248, 239, .05);
  border: 1px solid rgba(255, 248, 239, .12);
  border-radius: var(--radius-md);
  transition: border-color .25s var(--ease), transform .25s var(--ease), background-color .25s var(--ease);
}

.page-about .about-contenthub__item:hover {
  border-color: rgba(0, 229, 255, .45);
  transform: translateY(-3px);
  background: rgba(0, 229, 255, .06);
}

.page-about .about-contenthub__num {
  display: block;
  font-size: 13px;
  color: var(--neon);
  margin-bottom: 10px;
}

.page-about .about-contenthub__item h3 {
  font-family: var(--font-head);
  font-size: 17px;
  margin: 0 0 8px;
}

.page-about .about-contenthub__item h3 a {
  color: var(--paper);
  text-decoration: none;
  transition: color .2s var(--ease);
}

.page-about .about-contenthub__item h3 a:hover {
  color: var(--neon);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.page-about .about-contenthub__item p {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.75;
  color: rgba(244, 233, 216, .72);
  margin: 0;
}

/* ===== 测试版 ===== */
.page-about .about-testing {
  background: var(--paper-light);
}

.page-about .about-testing__grid {
  display: grid;
  gap: 32px;
  margin-top: 32px;
}

@media (min-width: 900px) {
  .page-about .about-testing__grid {
    grid-template-columns: 1.2fr 1fr;
    gap: 48px;
    margin-top: 44px;
  }
}

.page-about .about-testing__main h3 {
  font-family: var(--font-head);
  font-size: 20px;
  margin: 0 0 12px;
  color: var(--ink);
}

.page-about .about-testing__main p {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.9;
  color: var(--ink);
  margin: 0 0 16px;
}

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

.page-about .about-testing__aside {
  display: grid;
  gap: 18px;
  align-content: start;
}

.page-about .about-testing__card {
  background: var(--paper);
  border: 1px solid rgba(58, 58, 58, .14);
  border-radius: var(--radius-lg);
  padding: 24px;
}

.page-about .about-testing__card--cyber {
  background: var(--about-card-cyber), var(--paper);
  border: 1px solid rgba(0, 229, 255, .4);
}

.page-about .about-testing__card h3 {
  font-family: var(--font-head);
  font-size: 17px;
  margin: 0 0 12px;
  color: var(--ink);
}

.page-about .about-testing__card ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-testing__card li {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink);
  padding: 8px 0;
  border-bottom: 1px solid rgba(58, 58, 58, .1);
}

.page-about .about-testing__card li:last-child {
  border-bottom: none;
}

.page-about .about-testing__card p {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.85;
  color: var(--ink);
  margin: 0;
}

/* ===== 结尾引导 ===== */
.page-about .about-cta {
  background: var(--paper-warm);
}

.page-about .about-cta__inner {
  display: grid;
  gap: 20px;
  align-items: center;
  padding: 28px;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(180, 255, 58, .55);
  background: var(--about-card-accent);
  box-shadow: var(--shadow-card);
}

@media (min-width: 900px) {
  .page-about .about-cta__inner {
    grid-template-columns: 1fr auto;
    padding: 36px 40px;
  }
}

.page-about .about-cta__text h2 {
  font-family: var(--font-head);
  font-size: 24px;
  margin: 0 0 8px;
  color: var(--ink);
}

.page-about .about-cta__text p {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
  margin: 0;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta__actions .btn--accent {
  background: var(--ink);
  color: var(--neon);
  border: 1px solid var(--ink);
}

.page-about .about-cta__actions .btn--ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--ink);
}

.page-about .about-cta__actions .btn--accent:hover,
.page-about .about-cta__actions .btn--ghost:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(31, 31, 31, .16);
}

/* ===== 图片容器 ===== */
.page-about .about-timeline__figure,
.page-about .about-navshift__figure,
.page-about .about-contenthub__figure {
  margin-top: 44px;
  border-radius: var(--radius-lg);
}

.page-about .about-timeline__figure img,
.page-about .about-navshift__figure img,
.page-about .about-contenthub__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius-lg);
}

.page-about .about-timeline__figure figcaption,
.page-about .about-navshift__figure figcaption,
.page-about .about-contenthub__figure figcaption {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  margin-top: 10px;
  color: var(--ink-soft);
}

.page-about .about-contenthub__figure figcaption {
  color: rgba(244, 233, 216, .72);
}