/* ============ 品牌历程页 / page-about ============ */

.page-about {
  background: var(--ink);
  color: var(--cloud);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
  overflow-wrap: break-word;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 36px 0 56px;
  overflow: hidden;
  border-bottom: 2px solid var(--line);
  background:
    radial-gradient(760px 380px at 88% -12%, rgba(53, 230, 214, 0.17), transparent 62%),
    radial-gradient(620px 340px at 0% 110%, rgba(168, 107, 255, 0.15), transparent 64%),
    var(--ink);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(157, 176, 204, 0.075) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(157, 176, 204, 0.075) 1px, transparent 1px);
  background-size: 64px 64px;
}

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

/* 面包屑 */
.page-about .breadcrumb {
  margin: 0 0 26px;
}

.page-about .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  color: var(--mist);
}

.page-about .breadcrumb li {
  display: inline-flex;
  align-items: center;
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin: 0 10px;
  color: rgba(157, 176, 204, 0.5);
}

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

.page-about .breadcrumb a:hover {
  border-bottom-color: currentColor;
}

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

/* 首屏排版 */
.page-about .about-hero__grid {
  display: grid;
  gap: 36px;
  align-items: start;
}

.page-about .about-coord {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 18px;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.26em;
  color: var(--mist);
}

.page-about .about-coord::before {
  content: "";
  width: 36px;
  height: 2px;
  background: var(--gold);
  flex: none;
}

.page-about .about-hero h1 {
  margin: 0 0 22px;
  font-family: var(--font-head);
  font-size: clamp(32px, 7.4vw, 58px);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: 0.02em;
  color: var(--cloud);
}

.page-about .about-hero h1 .hl {
  color: var(--cyan);
}

.page-about .about-hero__lede {
  max-width: 40ch;
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(233, 238, 248, 0.9);
}

.page-about .about-hero__sub {
  max-width: 40ch;
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist);
}

/* 概览面板 */
.page-about .about-hero__panel {
  position: relative;
  border: 2px solid var(--line-strong);
  background: linear-gradient(158deg, rgba(42, 26, 94, 0.6), rgba(7, 34, 43, 0.6));
  box-shadow: var(--shadow-hard);
}

.page-about .about-hero__panel::after {
  content: "";
  position: absolute;
  right: -2px;
  bottom: -2px;
  width: 26px;
  height: 26px;
  background: var(--gold);
  clip-path: polygon(100% 0, 100% 100%, 0 100%);
}

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

.page-about .stat-list li {
  display: grid;
  grid-template-columns: 74px 1fr;
  gap: 14px;
  align-items: baseline;
  padding: 16px 22px;
  border-bottom: 1px solid var(--line);
}

.page-about .stat-list li:last-child {
  border-bottom: 0;
}

.page-about .stat-num {
  font-family: var(--font-num);
  font-size: 28px;
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--gold);
}

.page-about .stat-label {
  font-size: 14px;
  line-height: 1.6;
  color: var(--mist);
}

/* ---------- 章节标题通用 ---------- */
.page-about .section-head {
  margin-bottom: 36px;
}

.page-about .section-num {
  display: block;
  font-family: var(--font-num);
  font-size: 44px;
  line-height: 1;
  letter-spacing: 0.04em;
  color: var(--cyan);
  opacity: 0.85;
}

.page-about .section-kicker {
  margin: 10px 0 10px;
  font-size: 12px;
  letter-spacing: 0.3em;
  color: var(--mist);
}

.page-about .section-head h2 {
  margin: 0;
  max-width: 24ch;
  font-family: var(--font-head);
  font-size: clamp(25px, 5vw, 38px);
  font-weight: 900;
  line-height: 1.22;
  color: var(--cloud);
}

/* ---------- 时间轴 ---------- */
.page-about .about-track {
  padding: 62px 0 70px;
  border-bottom: 2px solid var(--line);
  background: linear-gradient(180deg, var(--teal) 0%, var(--ink) 94%);
}

.page-about .track-scale {
  display: block;
  width: 100%;
  max-width: 320px;
  height: auto;
  margin-top: 20px;
}

.page-about .timeline {
  position: relative;
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 42px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), rgba(53, 230, 214, 0.28) 52%, rgba(168, 107, 255, 0.6));
}

.page-about .tl-item {
  position: relative;
  padding-left: 44px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(53, 230, 214, 0.14), 0 0 16px rgba(53, 230, 214, 0.55);
}

.page-about .tl-item--current::before {
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(245, 184, 65, 0.18), 0 0 18px rgba(245, 184, 65, 0.6);
}

.page-about .tl-year {
  margin: 0 0 8px;
  font-family: var(--font-num);
  font-size: 13px;
  letter-spacing: 0.2em;
  color: var(--cyan);
}

.page-about .tl-item h3 {
  margin: 0 0 12px;
  font-family: var(--font-head);
  font-size: clamp(19px, 4vw, 25px);
  font-weight: 900;
  line-height: 1.3;
  color: var(--cloud);
}

.page-about .tl-item p {
  max-width: 60ch;
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(233, 238, 248, 0.86);
}

.page-about .tl-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 9px;
}

.page-about .tl-list li {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--mist);
}

.page-about .tl-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 9px;
  height: 2px;
  background: var(--violet);
}

/* ---------- 版本节奏 ---------- */
.page-about .about-versions {
  padding: 62px 0 70px;
  border-bottom: 2px solid var(--line);
  background: var(--ink);
}

.page-about .versions-figure {
  margin: 0 0 40px;
}

.page-about .version-cards {
  display: grid;
  gap: 20px;
  align-items: start;
}

.page-about .ver-card {
  min-height: 200px;
  padding: 22px 20px 24px;
  border: 2px solid var(--line);
  border-left: 5px solid var(--cyan);
  background: linear-gradient(180deg, rgba(42, 26, 94, 0.34), rgba(10, 22, 51, 0.55));
  box-shadow: var(--shadow-hard);
}

.page-about .ver-card--v2 {
  border-left-color: var(--violet);
}

.page-about .ver-card--v3 {
  border-left-color: var(--gold);
}

.page-about .ver-card--v4 {
  border-left-color: var(--cyan);
  background: linear-gradient(180deg, rgba(53, 230, 214, 0.14), rgba(10, 22, 51, 0.55));
}

.page-about .ver-tag {
  margin: 0 0 10px;
  font-family: var(--font-num);
  font-size: 26px;
  line-height: 1;
  letter-spacing: 0.05em;
  color: var(--gold);
}

.page-about .ver-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-size: 16px;
  font-weight: 900;
  line-height: 1.4;
  color: var(--cloud);
}

.page-about .ver-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 运营分工 ---------- */
.page-about .about-ops {
  padding: 62px 0 70px;
  border-bottom: 2px solid var(--line-violet);
  background: linear-gradient(142deg, var(--indigo) 0%, var(--ink) 80%);
}

.page-about .ops-grid {
  display: grid;
  gap: 36px;
  align-items: start;
}

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

.page-about .tablist {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
  padding-bottom: 14px;
  border-bottom: 2px solid var(--line);
}

.page-about .tab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 15px;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.03em;
  color: var(--mist);
  background: transparent;
  border: 2px solid var(--line);
  cursor: pointer;
  transition: background 200ms ease, color 200ms ease, border-color 200ms ease;
}

.page-about .tab:hover {
  color: var(--cloud);
  border-color: var(--line-violet);
}

.page-about .tab[aria-selected="true"] {
  color: var(--cloud);
  background: rgba(168, 107, 255, 0.26);
  border-color: var(--violet);
  box-shadow: inset 0 0 0 1px rgba(245, 184, 65, 0.55);
}

.page-about .tab-index {
  font-family: var(--font-num);
  font-size: 12px;
  color: var(--cyan);
}

.page-about .tabpanel {
  font-size: 16px;
  line-height: 1.85;
  color: rgba(233, 238, 248, 0.86);
}

.page-about .tabpanel[hidden] {
  display: none;
}

.page-about .tabpanel h3 {
  margin: 0 0 12px;
  font-family: var(--font-head);
  font-size: 20px;
  font-weight: 900;
  line-height: 1.35;
  color: var(--cloud);
}

.page-about .tabpanel p {
  max-width: 56ch;
  margin: 0 0 14px;
}

.page-about .tabpanel ul {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.page-about .tabpanel li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .tabpanel li::before {
  content: "";
  position: absolute;
  left: 1px;
  top: 10px;
  width: 7px;
  height: 7px;
  background: var(--cyan);
  transform: rotate(45deg);
}

.page-about .ops-figure {
  margin: 0;
}

/* ---------- 访问覆盖 ---------- */
.page-about .about-reach {
  padding: 62px 0 70px;
  border-bottom: 2px solid var(--line);
  background: linear-gradient(180deg, var(--wine) 0%, #2a0d1d 96%);
}

.page-about .reach-figure {
  margin: 0 0 34px;
}

.page-about .reach-grid {
  display: grid;
  gap: 22px;
}

.page-about .reach-item {
  padding-top: 16px;
  border-top: 2px solid rgba(233, 238, 248, 0.28);
}

.page-about .reach-item .num {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-num);
  font-size: 34px;
  line-height: 1;
  color: var(--gold);
}

.page-about .reach-item h3 {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-size: 17px;
  font-weight: 900;
  color: var(--cloud);
}

.page-about .reach-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: rgba(233, 238, 248, 0.82);
}

/* ---------- 协作与评审 ---------- */
.page-about .about-partners {
  padding: 62px 0 72px;
  background: linear-gradient(168deg, var(--teal) 0%, var(--ink) 86%);
}

.page-about .partner-grid {
  display: grid;
  gap: 18px;
}

.page-about .partner-card {
  padding: 22px 20px 24px;
  border: 2px solid var(--line);
  border-top: 4px solid var(--cyan);
  background: rgba(10, 22, 51, 0.55);
}

.page-about .partner-card:nth-child(2) {
  border-top-color: var(--violet);
}

.page-about .partner-card--wide {
  border-top-color: var(--gold);
  background: linear-gradient(150deg, rgba(94, 27, 51, 0.42), rgba(10, 22, 51, 0.6));
}

.page-about .partner-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 900;
  color: var(--cloud);
}

.page-about .partner-card p {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(233, 238, 248, 0.84);
}

/* 底部入口 */
.page-about .about-links {
  margin-top: 44px;
  padding-top: 28px;
  border-top: 2px solid var(--line-strong);
}

.page-about .about-links h2 {
  margin: 0 0 20px;
  font-family: var(--font-head);
  font-size: clamp(19px, 4vw, 24px);
  font-weight: 900;
  color: var(--cloud);
}

.page-about .link-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .about-hero {
    padding: 44px 0 64px;
  }

  .page-about .reach-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 26px;
  }

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

  .page-about .partner-card--wide {
    grid-column: 1 / -1;
  }

  .page-about .version-cards {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 52px 0 76px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: 1.4fr 1fr;
    gap: 56px;
  }

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

  .page-about .stat-list li {
    grid-template-columns: 82px 1fr;
  }

  .page-about .stat-num {
    font-size: 32px;
  }

  .page-about .timeline {
    gap: 52px;
  }

  .page-about .tl-item {
    padding-left: 56px;
  }

  .page-about .ops-grid {
    grid-template-columns: 7fr 5fr;
    gap: 48px;
  }

  .page-about .ops-figure {
    margin-top: 6px;
  }

  .page-about .about-track,
  .page-about .about-versions,
  .page-about .about-ops,
  .page-about .about-reach,
  .page-about .about-partners {
    padding-top: 78px;
    padding-bottom: 86px;
  }
}

@media (min-width: 1080px) {
  .page-about .version-cards {
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
  }

  .page-about .ver-card {
    min-height: 224px;
  }

  .page-about .ver-card--v2 {
    margin-top: 30px;
  }

  .page-about .ver-card--v3 {
    margin-top: 60px;
  }

  .page-about .ver-card--v4 {
    margin-top: 90px;
  }

  .page-about .section-head h2 {
    max-width: 26ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tab,
  .page-about .breadcrumb a {
    transition: none;
  }
}