.page-about {
  --about-rail-w: 200px;
  --about-dot: 14px;
  --about-pad-y: 30px;
  display: block;
}

.page-about .about-shell {
  padding-block: clamp(18px, 3vw, 34px) clamp(48px, 7vw, 96px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  isolation: isolate;
  display: grid;
  gap: var(--gap);
  margin-top: 18px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -40px;
  right: -10px;
  width: 60%;
  height: 320px;
  background: linear-gradient(135deg, rgba(55, 242, 208, 0.16), rgba(55, 242, 208, 0) 72%);
  clip-path: polygon(16% 0, 100% 0, 100% 100%, 0 78%);
  pointer-events: none;
  z-index: 0;
}

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

.page-about .about-hero .display-title {
  margin: 12px 0 0;
  font-size: clamp(30px, 5.4vw, 64px);
  line-height: 1.08;
  letter-spacing: -0.01em;
}

.page-about .about-hero .lede {
  margin: 18px 0 0;
  max-width: 64ch;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-hero-actions .btn {
  text-decoration: none;
}

.page-about .about-hero-figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: var(--panel);
}

.page-about .about-hero-figure img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 4 / 3;
}

.page-about .about-hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero-stats li {
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: linear-gradient(160deg, rgba(11, 42, 35, 0.95), rgba(6, 26, 21, 0.95));
}

.page-about .about-hero-stats .stat-number {
  display: block;
  font-size: clamp(20px, 3vw, 32px);
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .about-stat-label {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  line-height: 1.5;
  color: var(--muted);
}

/* ---------- 章节头 ---------- */
.page-about .about-section-head {
  margin-top: clamp(48px, 7vw, 88px);
  max-width: 70ch;
}

.page-about .about-section-head h2 {
  margin: 10px 0 0;
  font-size: clamp(24px, 3.4vw, 40px);
  line-height: 1.2;
  color: var(--ivory);
}

.page-about .about-section-lede {
  margin: 14px 0 0;
  color: var(--muted);
  line-height: 1.75;
}

/* ---------- 时间轴 ---------- */
.page-about .about-track {
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-stage {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  row-gap: 14px;
  padding: var(--about-pad-y) 0 var(--about-pad-y) 28px;
  scroll-margin-top: 96px;
}

.page-about .about-stage::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 5px;
  width: 2px;
  background: linear-gradient(180deg, var(--line), rgba(29, 74, 62, 0.35));
}

.page-about .about-stage:first-child::before {
  top: var(--about-pad-y);
}

.page-about .about-stage:last-child::before {
  bottom: var(--about-pad-y);
}

.page-about .about-stage-rail {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
}

.page-about .about-stage-rail::before {
  content: "";
  position: absolute;
  left: -29px;
  top: 50%;
  width: var(--about-dot);
  height: var(--about-dot);
  transform: translateY(-50%);
  border: 2px solid var(--cyan);
  border-radius: 50%;
  background: var(--bg);
  box-shadow: 0 0 0 4px rgba(55, 242, 208, 0.12);
}

.page-about .about-stage-year {
  font-size: 22px;
  line-height: 1;
  color: var(--cyan);
  letter-spacing: 0.04em;
}

.page-about .about-stage-tag {
  display: inline-block;
  padding: 4px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--mist);
  white-space: nowrap;
}

.page-about .about-stage-main {
  max-width: 68ch;
}

.page-about .about-stage-title {
  margin: 0;
  font-size: clamp(20px, 2.5vw, 28px);
  line-height: 1.32;
  color: var(--ivory);
}

.page-about .about-stage-main p {
  margin: 14px 0 0;
  color: var(--muted);
  line-height: 1.78;
}

.page-about .about-inline-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(55, 242, 208, 0.4);
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease);
}

.page-about .about-inline-link:hover,
.page-about .about-inline-link:focus-visible {
  color: var(--mist);
  border-bottom-color: var(--mist);
}

/* ---------- 事实数字 ---------- */
.page-about .about-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-fact {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 9px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(11, 42, 35, 0.72);
  transition: border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .about-fact:hover,
.page-about .about-fact:focus-within {
  border-color: var(--cyan);
  background: rgba(55, 242, 208, 0.1);
}

.page-about .about-fact-num {
  font-size: 18px;
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .about-fact-label {
  font-size: 13px;
  color: var(--muted);
}

/* ---------- 折线图 ---------- */
.page-about .about-chart {
  margin: 24px 0 0;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(120% 130% at 0% 0%, rgba(55, 242, 208, 0.1), transparent 62%),
    var(--panel);
}

.page-about .about-chart svg {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
}

.page-about .about-chart-grid line {
  stroke: var(--line);
  stroke-width: 1;
}

.page-about .about-chart-line {
  stroke: var(--cyan);
  stroke-width: 2.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.page-about .about-chart-dots circle {
  fill: var(--bg);
  stroke: var(--cyan);
  stroke-width: 2;
}

.page-about .about-chart-labels text {
  fill: var(--muted);
  font-size: 12px;
  font-family: var(--font-mono);
}

.page-about .about-chart figcaption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 会员三栏 ---------- */
.page-about .about-plans {
  display: grid;
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-plan {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(165deg, rgba(11, 42, 35, 0.96), rgba(6, 26, 21, 0.96));
  transition: border-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .about-plan:hover {
  border-color: var(--cyan);
  transform: translateY(-2px);
}

.page-about .about-plan-name {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.page-about .about-plan-price {
  margin: 10px 0 0;
  font-size: 30px;
  line-height: 1.1;
  color: var(--amber);
}

.page-about .about-plan-price span {
  margin-left: 5px;
  font-family: var(--font-body);
  font-size: 12px;
  color: var(--muted);
}

.page-about .about-plan-quota {
  margin: 8px 0 0;
  font-size: 16px;
  color: var(--ivory);
}

.page-about .about-plan-note {
  margin: 8px 0 0;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-member-figure {
  margin: 20px 0 0;
  max-width: 380px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--panel);
}

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

.page-about .about-stage-cta {
  margin: 20px 0 0;
}

.page-about .about-stage-cta .btn {
  text-decoration: none;
}

/* ---------- 团队图 ---------- */
.page-about .about-team-figure {
  margin: 22px 0 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--panel);
}

.page-about .about-team-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 3 / 2;
}

/* ---------- 内链区 ---------- */
.page-about .about-links {
  display: grid;
  gap: 10px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-links a {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--panel);
  color: var(--ivory);
  text-decoration: none;
  transition: border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .about-links a:hover,
.page-about .about-links a:focus-visible {
  border-color: var(--cyan);
  background: rgba(55, 242, 208, 0.08);
}

.page-about .about-link-title {
  font-size: 16px;
  font-weight: 600;
}

.page-about .about-link-desc {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 桌面 ---------- */
@media (min-width: 920px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    grid-template-areas:
      "copy figure"
      "stats figure";
    align-items: start;
    column-gap: clamp(24px, 3vw, 44px);
  }

  .page-about .about-hero-copy {
    grid-area: copy;
  }

  .page-about .about-hero-figure {
    grid-area: figure;
    align-self: stretch;
  }

  .page-about .about-hero-figure img {
    height: 100%;
    aspect-ratio: auto;
    min-height: 340px;
  }

  .page-about .about-hero-stats {
    grid-area: stats;
    align-self: end;
    margin-top: 8px;
  }

  .page-about .about-plans {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .about-links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-stage {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    column-gap: clamp(24px, 3vw, 48px);
    padding: 44px 0;
    row-gap: 0;
  }

  .page-about .about-stage::before {
    left: var(--about-rail-w);
  }

  .page-about .about-stage:first-child::before {
    top: 44px;
  }

  .page-about .about-stage:last-child::before {
    bottom: 44px;
  }

  .page-about .about-stage-rail {
    flex-direction: column;
    align-items: flex-end;
    text-align: right;
    gap: 10px;
    padding-right: 22px;
  }

  .page-about .about-stage-rail::before {
    left: auto;
    right: -8px;
    top: 14px;
    transform: none;
  }

  .page-about .about-stage-year {
    font-size: clamp(40px, 4.4vw, 66px);
    letter-spacing: 0.02em;
  }

  .page-about .about-stage-tag {
    font-size: 12px;
  }

  .page-about .about-stage-main {
    max-width: none;
  }

  .page-about .about-member-figure {
    max-width: 420px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-plan,
  .page-about .about-fact,
  .page-about .about-links a,
  .page-about .about-inline-link {
    transition: none;
  }

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