.page-about {
  --about-line: rgba(212, 175, 55, .2);
  --about-line-soft: rgba(212, 175, 55, .12);
  --about-text: rgba(245, 241, 232, .78);
  --about-text-soft: rgba(245, 241, 232, .6);
  background: var(--violet-900);
  color: var(--paper);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding: 30px 0 52px;
  background:
    radial-gradient(120% 92% at 80% -12%, rgba(74, 29, 110, .9), transparent 62%),
    radial-gradient(90% 70% at 4% 108%, rgba(46, 139, 87, .22), transparent 66%),
    var(--violet-900);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: -20% -12% -10% 40%;
  background:
    linear-gradient(118deg, transparent 0 45.4%, rgba(212, 175, 55, .16) 45.6% 45.8%, transparent 46%),
    linear-gradient(118deg, transparent 0 51.4%, rgba(143, 217, 232, .12) 51.6% 51.8%, transparent 52%);
  pointer-events: none;
}

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

.page-about .breadcrumb {
  font-size: 13px;
  margin-bottom: 22px;
}

.page-about .breadcrumb ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--about-text-soft);
}

.page-about .breadcrumb a {
  color: var(--about-text);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .breadcrumb a:hover {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

.page-about .breadcrumb [aria-current="page"] {
  color: var(--gold);
}

.page-about .eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--ice);
  margin: 0;
}

.page-about .about-hero-grid {
  display: grid;
  gap: 30px;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: 28px;
  line-height: 1.3;
  letter-spacing: .02em;
  color: var(--paper);
  margin: 14px 0 0;
  max-width: 22em;
}

.page-about .page-lead {
  color: var(--about-text);
  font-size: 16px;
  line-height: 1.9;
  margin: 18px 0 0;
  max-width: 32em;
}

.page-about .about-hero-actions {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .about-hero-figure {
  margin: 0;
  border: 1px solid var(--about-line);
  background: rgba(122, 63, 166, .14);
  position: relative;
}

.page-about .about-hero-figure::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  width: 26px;
  height: 26px;
  border-top: 2px solid var(--gold);
  border-left: 2px solid var(--gold);
  pointer-events: none;
  z-index: 2;
}

.page-about .about-hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  opacity: .94;
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 44px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-facts .stat {
  background: var(--violet-900);
  padding: 18px 20px;
  display: grid;
  gap: 5px;
}

.page-about .about-facts .stat-num {
  font-family: var(--font-mono);
  font-size: 24px;
  color: var(--gold);
  letter-spacing: .04em;
}

.page-about .about-facts .stat-label {
  font-size: 13px;
  color: var(--about-text-soft);
}

/* ---------- 正文轨道 ---------- */

.page-about .about-body {
  padding: 4px 0 72px;
  background: linear-gradient(180deg, var(--violet-900), var(--violet-800) 42%, var(--violet-900));
}

.page-about .about-shell {
  position: relative;
}

.page-about .about-sec {
  position: relative;
  padding: 48px 0;
  border-top: 1px solid var(--about-line-soft);
}

.page-about .about-sec:first-child {
  border-top: 0;
  padding-top: 26px;
}

.page-about .about-sec h2 {
  font-family: var(--font-display);
  font-size: 23px;
  line-height: 1.38;
  letter-spacing: .02em;
  color: var(--paper);
  margin: 0 0 16px;
  max-width: 20em;
}

.page-about .about-sec h3 {
  font-family: var(--font-display);
  font-size: 17px;
  line-height: 1.5;
  letter-spacing: .02em;
  color: var(--paper);
  margin: 0 0 8px;
}

.page-about .about-sec > p {
  color: var(--about-text);
  line-height: 1.9;
  max-width: 36em;
  margin: 0 0 14px;
}

.page-about .about-sec .grid {
  margin-top: 26px;
}

/* ---------- 01 使用场景 ---------- */

.page-about .about-check {
  position: relative;
  padding: 22px 22px 22px 26px;
  background: rgba(122, 63, 166, .16);
  border: 1px solid var(--about-line-soft);
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-check::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  bottom: -1px;
  width: 3px;
  background: var(--green-600);
}

.page-about .about-check:hover {
  border-color: var(--gold-edge);
  background: rgba(122, 63, 166, .26);
}

.page-about .about-check p {
  color: var(--about-text);
  font-size: 15px;
  line-height: 1.85;
  margin: 0;
}

/* ---------- 02 版本代际 ---------- */

.page-about .about-gen {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  position: relative;
}

.page-about .about-gen::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 34px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold-line) 0, rgba(212, 175, 55, .06) 100%);
}

.page-about .about-gen-item {
  position: relative;
  padding: 0 0 26px 30px;
}

.page-about .about-gen-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--violet-900);
  border: 2px solid var(--gold);
  transition: background var(--dur) var(--ease);
}

.page-about .about-gen-item[data-state="current"]::before {
  background: var(--green-600);
  border-color: var(--green-600);
  box-shadow: 0 0 0 5px rgba(46, 139, 87, .22);
}

.page-about .about-gen-code {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--gold);
  margin-bottom: 6px;
}

.page-about .about-gen-item[data-state="current"] .about-gen-code {
  color: var(--ice);
}

.page-about .about-gen-item p {
  color: var(--about-text);
  font-size: 15px;
  line-height: 1.85;
  margin: 0;
  max-width: 34em;
}

/* ---------- 03 内容中心 ---------- */

.page-about .about-archive {
  display: grid;
  gap: 16px;
  margin-top: 26px;
}

.page-about .about-archive-card {
  position: relative;
  border: 1px solid var(--about-line-soft);
  background: linear-gradient(180deg, rgba(122, 63, 166, .18), rgba(26, 11, 41, .55));
  transition: border-color var(--dur) var(--ease);
}

.page-about .about-archive-card::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  width: 20px;
  height: 20px;
  border-top: 2px solid var(--gold);
  border-left: 2px solid var(--gold);
  pointer-events: none;
}

.page-about .about-archive-card:hover {
  border-color: var(--gold-edge);
}

.page-about .about-archive-trigger {
  display: flex;
  align-items: baseline;
  gap: 12px;
  width: 100%;
  padding: 20px 22px 14px;
  background: none;
  border: 0;
  text-align: left;
  cursor: pointer;
  color: var(--paper);
  font-family: var(--font-display);
  font-size: 18px;
  letter-spacing: .02em;
  transition: color var(--dur) var(--ease);
}

.page-about .about-archive-trigger:hover {
  color: var(--gold);
}

.page-about .about-archive-code {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--gold);
  flex: 0 0 auto;
}

.page-about .about-archive-panel {
  padding: 0 22px 20px;
}

.page-about .about-archive-panel p {
  color: var(--about-text);
  font-size: 15px;
  line-height: 1.85;
  margin: 0 0 12px;
}

.page-about .about-archive-panel ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .about-archive-panel li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-text-soft);
}

.page-about .about-archive-panel li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .78em;
  width: 6px;
  height: 1px;
  background: var(--gold);
}

/* ---------- 04 团队与流程 ---------- */

.page-about .about-flow {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .about-flow-step {
  position: relative;
  background: var(--violet-900);
  padding: 24px 22px 26px;
  transition: background var(--dur) var(--ease);
}

.page-about .about-flow-step::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--gold), transparent);
  opacity: 0;
  transition: opacity var(--dur) var(--ease);
}

.page-about .about-flow-step:hover {
  background: var(--violet-800);
}

.page-about .about-flow-step:hover::after,
.page-about .about-flow-step:focus-within::after {
  opacity: 1;
}

.page-about .about-flow-code {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--gold);
  margin-bottom: 10px;
}

.page-about .about-flow-step p {
  color: var(--about-text);
  font-size: 15px;
  line-height: 1.85;
  margin: 0;
}

.page-about .about-flow-figure {
  margin: 26px 0 0;
  border: 1px solid var(--about-line-soft);
  background: rgba(26, 11, 41, .5);
  padding: 14px;
}

.page-about .about-flow-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  opacity: .9;
}

.page-about .about-flow-figure .figure-cap {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--about-text-soft);
}

/* ---------- 05 地区覆盖 ---------- */

.page-about .about-region {
  display: grid;
  gap: 28px;
  margin-top: 24px;
  align-items: start;
}

.page-about .about-region-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line-soft);
  border: 1px solid var(--about-line-soft);
}

.page-about .about-region-list li {
  background: var(--violet-900);
  padding: 16px 18px;
  display: grid;
  gap: 6px;
  transition: background var(--dur) var(--ease);
}

.page-about .about-region-list li:hover {
  background: var(--violet-800);
}

.page-about .about-region-key {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--ice);
}

.page-about .about-region-list li > span:last-child {
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-text);
}

.page-about .about-region-note {
  margin: 18px 0 0;
  padding-left: 16px;
  border-left: 2px solid var(--pink);
  font-size: 14px;
  line-height: 1.85;
  color: var(--about-text-soft);
  max-width: 34em;
}

.page-about .about-region-figure {
  margin: 0;
  border: 1px solid var(--about-line-soft);
  background: rgba(46, 139, 87, .08);
  padding: 14px;
}

.page-about .about-region-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  opacity: .88;
}

/* ---------- 06 更新节奏 ---------- */

.page-about .about-cadence {
  margin-top: 26px;
}

.page-about .about-cadence-item {
  position: relative;
  padding: 20px 20px 22px;
  background: rgba(26, 11, 41, .55);
  border: 1px solid var(--about-line-soft);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-cadence-item:hover {
  border-color: var(--gold-edge);
}

.page-about .about-cadence-code {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--violet-900);
  background: var(--gold);
  padding: 3px 10px;
  margin-bottom: 12px;
}

.page-about .about-cadence-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-text);
}

/* ---------- 页尾导航块 ---------- */

.page-about .about-next {
  margin-top: 8px;
  padding: 32px 24px 30px;
  border: 1px solid var(--about-line);
  background: rgba(46, 139, 87, .1);
}

.page-about .about-next-lead {
  font-family: var(--font-display);
  font-size: 18px;
  letter-spacing: .02em;
  color: var(--paper);
  margin: 0 0 18px;
}

.page-about .about-next-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line-soft);
}

.page-about .about-next-list li {
  background: var(--violet-900);
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 14px 16px;
  transition: background var(--dur) var(--ease);
}

.page-about .about-next-list li:hover {
  background: var(--violet-800);
}

.page-about .about-next-list a {
  font-family: var(--font-display);
  font-size: 16px;
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease);
}

.page-about .about-next-list a:hover {
  border-bottom-color: var(--gold);
}

.page-about .about-next-list span {
  font-size: 14px;
  line-height: 1.7;
  color: var(--about-text-soft);
}

/* ---------- 断点 ---------- */

@media (min-width: 720px) {
  .page-about .about-hero {
    padding: 40px 0 66px;
  }

  .page-about .about-hero h1 {
    font-size: 38px;
  }

  .page-about .about-sec h2 {
    font-size: 28px;
  }

  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .about-flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-region {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, .75fr);
    gap: 36px;
  }

  .page-about .about-flow-step p {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 200ms var(--ease), opacity 200ms var(--ease);
  }

  .page-about .about-flow-step:hover p,
  .page-about .about-flow-step:focus-within p {
    max-height: 10em;
    opacity: 1;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
    gap: 52px;
    align-items: start;
  }

  .page-about .about-hero h1 {
    font-size: 44px;
  }

  .page-about .about-facts {
    margin-top: 52px;
  }

  .page-about .about-body {
    padding-bottom: 96px;
  }
}

@media (min-width: 960px) {
  .page-about .about-shell {
    padding-left: 92px;
  }

  .page-about .about-shell::before {
    content: "";
    position: absolute;
    left: 52px;
    top: 6px;
    bottom: 6px;
    width: 1px;
    background: linear-gradient(180deg, transparent 0, var(--gold-line) 6%, var(--gold-line) 94%, transparent 100%);
  }

  .page-about .about-sec {
    padding: 60px 0;
  }

  .page-about .about-sec::before {
    content: attr(data-step);
    position: absolute;
    left: -92px;
    top: 66px;
    width: 34px;
    text-align: right;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: .16em;
    color: var(--gold);
  }

  .page-about .about-sec::after {
    content: "";
    position: absolute;
    left: -44px;
    top: 70px;
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--gold);
  }

  .page-about .about-sec:first-child::before,
  .page-about .about-sec:first-child::after {
    top: 34px;
  }

  .page-about .about-cadence {
    gap: 1px;
  }

  .page-about .about-archive {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero h1 {
    font-size: 48px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: 1ms !important;
  }
}