.page-about {
  --ab-gold-line: rgba(176, 141, 87, 0.34);
  --ab-gold-line-soft: rgba(176, 141, 87, 0.16);
  --ab-ink-soft: rgba(28, 28, 28, 0.78);
  --ab-paper-soft: rgba(245, 240, 230, 0.74);
  --ab-mute-line: rgba(138, 115, 78, 0.28);
  --ab-card-cut: 16px;
  display: block;
  background: var(--nn-green-deep);
}

.page-about .nn-media {
  position: relative;
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--ab-gold-line-soft);
  background: var(--nn-green-deep);
}

.page-about .nn-media__img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .nn-media__caption {
  display: block;
  padding: 0.7rem 0.9rem;
  font-family: var(--nn-font-index);
  font-size: 0.76rem;
  letter-spacing: 0.04em;
  line-height: 1.6;
  color: var(--ab-paper-soft);
  background: rgba(6, 38, 29, 0.9);
  border-top: 1px solid var(--ab-gold-line-soft);
}

.ab-kicker--gold {
  color: var(--nn-gold-soft);
}

.ab-kicker--ink {
  color: var(--nn-gold-mute);
}

/* ---------- 首屏 ---------- */

.ab-hero {
  position: relative;
  overflow: hidden;
  padding-top: calc(var(--nn-header-h) + clamp(3rem, 8vw, 6.5rem));
  padding-bottom: clamp(3rem, 7vw, 5.5rem);
  background:
    radial-gradient(120% 90% at 88% 4%, rgba(176, 141, 87, 0.20) 0%, rgba(176, 141, 87, 0) 58%),
    linear-gradient(168deg, var(--nn-green) 0%, var(--nn-green) 32%, var(--nn-green-deep) 100%);
}

.ab-hero::after {
  content: "";
  position: absolute;
  top: 14%;
  right: -10%;
  width: min(520px, 80vw);
  height: 1px;
  background: linear-gradient(90deg, rgba(176, 141, 87, 0) 0%, rgba(176, 141, 87, 0.55) 55%, rgba(176, 141, 87, 0) 100%);
  transform: rotate(-22deg);
  transform-origin: right center;
  pointer-events: none;
}

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

.ab-hero__kicker {
  margin: clamp(1.6rem, 4vw, 2.6rem) 0 0;
  color: var(--nn-gold-soft);
}

.ab-hero__title {
  margin: 0.9rem 0 0;
  max-width: 16ch;
  font-family: var(--nn-font-display);
  font-weight: 400;
  font-size: clamp(2.5rem, 8.6vw, 5.6rem);
  line-height: 1.02;
  letter-spacing: -0.015em;
  color: var(--nn-paper);
}

.ab-hero__lede {
  margin: clamp(1.3rem, 3.5vw, 2rem) 0 0;
  max-width: 62ch;
  font-size: clamp(1rem, 0.35vw + 0.95rem, 1.14rem);
  line-height: 1.9;
  color: var(--ab-paper-soft);
}

.ab-hero__metrics {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin: clamp(2rem, 5vw, 3.2rem) 0 0;
  padding: 0;
  border-top: 1px solid var(--ab-gold-line);
}

.ab-metric {
  padding: clamp(1rem, 2.6vw, 1.5rem) clamp(0.7rem, 2vw, 1.4rem) 0 0;
  border-right: 1px solid var(--ab-gold-line-soft);
}

.ab-metric:last-child {
  border-right: 0;
}

.ab-metric__num {
  display: block;
  font-family: var(--nn-font-display);
  font-weight: 500;
  font-size: clamp(1.4rem, 4.4vw, 2.3rem);
  line-height: 1;
  color: var(--nn-gold-soft);
}

.ab-metric__label {
  display: block;
  margin-top: 0.6rem;
  font-family: var(--nn-font-index);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  line-height: 1.5;
  color: rgba(245, 240, 230, 0.56);
}

/* ---------- 起手 ---------- */

.ab-origin {
  position: relative;
  overflow: hidden;
  padding-top: clamp(3rem, 7vw, 5.5rem);
  padding-bottom: clamp(3rem, 7vw, 5.5rem);
  background: linear-gradient(180deg, var(--nn-green-deep) 0%, #082E23 55%, var(--nn-green-deep) 100%);
}

.ab-origin::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(-32deg, rgba(176, 141, 87, 0.055) 0 1px, transparent 1px 26px);
  pointer-events: none;
}

.ab-origin__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(1.8rem, 5vw, 3.2rem);
}

.ab-origin__title {
  margin: 0.9rem 0 0;
  color: var(--nn-paper);
  font-family: var(--nn-font-display);
  font-weight: 400;
}

.ab-origin__prose {
  margin-top: clamp(1.2rem, 3vw, 1.8rem);
}

.ab-origin__prose p {
  color: var(--ab-paper-soft);
  line-height: 1.95;
}

.ab-origin__prose p + p {
  margin-top: 1.1rem;
}

.ab-origin__sign {
  margin: clamp(1.4rem, 3vw, 2rem) 0 0;
  padding-left: 0.9rem;
  border-left: 2px solid var(--nn-red);
  font-family: var(--nn-font-index);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  color: var(--nn-gold-soft);
}

/* ---------- 三大板块 ---------- */

.ab-pillars {
  padding-top: clamp(3rem, 7vw, 5.5rem);
  padding-bottom: clamp(3rem, 7vw, 5.5rem);
  background: linear-gradient(180deg, #EFE7D9 0%, var(--nn-paper) 40%, var(--nn-paper) 100%);
  color: var(--nn-ink);
}

.ab-pillars__head {
  display: grid;
  gap: 1.2rem;
  margin-bottom: clamp(2rem, 4.5vw, 3.2rem);
}

.ab-pillars__title {
  margin: 0.8rem 0 0;
  font-family: var(--nn-font-display);
  font-weight: 400;
  color: var(--nn-ink);
}

.ab-pillars__intro {
  margin: 0;
  max-width: 46ch;
  font-size: 0.98rem;
  line-height: 1.9;
  color: var(--ab-ink-soft);
}

.ab-pillars__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.ab-pillar {
  display: grid;
  gap: 0.8rem;
  padding: clamp(1.4rem, 3.2vw, 2.2rem) 0;
  border-top: 1px solid var(--ab-mute-line);
}

.ab-pillar:last-child {
  border-bottom: 1px solid var(--ab-mute-line);
}

.ab-pillar__num {
  font-family: var(--nn-font-display);
  font-weight: 300;
  font-size: clamp(2.4rem, 7vw, 4.2rem);
  line-height: 1;
  color: var(--nn-gold);
  opacity: 0.5;
}

.ab-pillar__title {
  margin: 0;
  font-family: var(--nn-font-display);
  font-weight: 500;
  color: var(--nn-ink);
}

.ab-pillar__body p {
  margin: 0.8rem 0 0;
  max-width: 62ch;
  font-size: 0.97rem;
  line-height: 1.9;
  color: var(--ab-ink-soft);
}

.ab-pillar__meta {
  font-family: var(--nn-font-index);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  color: var(--nn-red);
}

/* ---------- 云南 ---------- */

.ab-yunnan {
  position: relative;
  overflow: hidden;
  padding-top: clamp(3rem, 7vw, 5.5rem);
  padding-bottom: clamp(3rem, 7vw, 5.5rem);
  background: linear-gradient(200deg, var(--nn-green) 0%, var(--nn-green-soft) 46%, var(--nn-green-deep) 100%);
  color: var(--nn-paper);
}

.ab-yunnan__grid {
  display: grid;
  gap: clamp(1.8rem, 5vw, 3.4rem);
}

.ab-yunnan__title {
  margin: 0.9rem 0 0;
  font-family: var(--nn-font-display);
  font-weight: 400;
  color: var(--nn-paper);
}

.ab-yunnan__prose {
  margin-top: clamp(1.2rem, 3vw, 1.8rem);
}

.ab-yunnan__prose p {
  color: var(--ab-paper-soft);
  line-height: 1.95;
}

.ab-yunnan__prose p + p {
  margin-top: 1.1rem;
}

/* ---------- 团队 ---------- */

.ab-team {
  padding-top: clamp(3rem, 7vw, 5.5rem);
  padding-bottom: clamp(3rem, 7vw, 5.5rem);
  background: var(--nn-paper);
  color: var(--nn-ink);
}

.ab-team__grid {
  display: grid;
  gap: clamp(1.8rem, 4.5vw, 3.2rem);
}

.ab-team__title {
  margin: 0.8rem 0 0;
  font-family: var(--nn-font-display);
  font-weight: 400;
  color: var(--nn-ink);
}

.ab-team__prose {
  margin-top: clamp(1.2rem, 3vw, 1.6rem);
}

.ab-team__prose p {
  color: var(--ab-ink-soft);
  line-height: 1.95;
}

.ab-team__prose p + p {
  margin-top: 1.1rem;
}

.ab-stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 1px;
  background: var(--ab-mute-line);
  align-content: start;
}

.ab-stat {
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  min-height: clamp(6.5rem, 16vw, 8.5rem);
  padding: clamp(1rem, 2.6vw, 1.5rem);
  background: var(--nn-paper);
}

.ab-stat__num {
  display: block;
  font-family: var(--nn-font-display);
  font-weight: 500;
  font-size: clamp(1.4rem, 4vw, 2rem);
  line-height: 1;
  color: var(--nn-green);
}

.ab-stat__label {
  display: block;
  margin-top: 0.6rem;
  font-family: var(--nn-font-index);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--nn-gold-mute);
}

/* ---------- 时间轴 ---------- */

.ab-timeline {
  padding-top: clamp(3rem, 7vw, 5.5rem);
  padding-bottom: clamp(3rem, 7vw, 5.5rem);
  background: linear-gradient(180deg, var(--nn-paper) 0%, #EDE4D4 100%);
  color: var(--nn-ink);
}

.ab-timeline__top {
  display: grid;
  gap: clamp(1.5rem, 4vw, 2.6rem);
  margin-bottom: clamp(2.2rem, 5vw, 3.4rem);
}

.ab-timeline__title {
  margin: 0.8rem 0 0;
  font-family: var(--nn-font-display);
  font-weight: 400;
  color: var(--nn-ink);
}

.ab-timeline__intro {
  margin: 1rem 0 0;
  max-width: 52ch;
  font-size: 0.98rem;
  line-height: 1.9;
  color: var(--ab-ink-soft);
}

.ab-timeline__media {
  max-width: 100%;
}

.ab-track {
  list-style: none;
  position: relative;
  margin: 0;
  padding: 0;
}

.ab-track::before {
  content: "";
  position: absolute;
  top: 0.6rem;
  bottom: 0.6rem;
  left: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--nn-gold) 0%, rgba(176, 141, 87, 0.34) 62%, rgba(176, 141, 87, 0) 100%);
}

.ab-track__item {
  position: relative;
  padding: 0 0 clamp(2rem, 4.5vw, 2.8rem) 2.4rem;
}

.ab-track__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.45rem;
  width: 17px;
  height: 17px;
  border-radius: 50%;
  background: var(--nn-red);
  box-shadow: 0 0 0 4px var(--nn-paper), 0 0 0 5px rgba(176, 141, 87, 0.4);
}

.ab-track__badge {
  display: inline-block;
  padding: 0.3rem 0.7rem;
  border: 1px solid var(--ab-mute-line);
  font-family: var(--nn-font-index);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--nn-gold-mute);
  white-space: nowrap;
}

.ab-track__card {
  margin-top: 0.9rem;
  padding: clamp(1.1rem, 2.6vw, 1.6rem) clamp(1.1rem, 2.6vw, 1.8rem);
  background: rgba(255, 255, 255, 0.5);
  border: 1px solid var(--ab-mute-line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--ab-card-cut)), calc(100% - var(--ab-card-cut)) 100%, 0 100%);
  transition: background-color 0.3s var(--nn-ease), box-shadow 0.3s var(--nn-ease);
}

.ab-track__card:hover {
  background: rgba(255, 255, 255, 0.82);
  box-shadow: 0 18px 34px -28px rgba(6, 38, 29, 0.6);
}

.ab-track__title {
  margin: 0;
  font-family: var(--nn-font-display);
  font-weight: 500;
  color: var(--nn-ink);
}

.ab-track__card p {
  margin: 0.7rem 0 0;
  max-width: 62ch;
  font-size: 0.95rem;
  line-height: 1.88;
  color: var(--ab-ink-soft);
}

.ab-timeline__more {
  margin: clamp(0.5rem, 2vw, 1rem) 0 0;
  padding-top: 1.2rem;
  border-top: 1px solid var(--ab-mute-line);
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--ab-ink-soft);
}

.ab-timeline__link {
  color: var(--nn-red);
  text-decoration: underline;
  text-underline-offset: 0.22em;
}

.ab-timeline__link:hover {
  color: var(--nn-green);
}

/* ---------- 收尾 ---------- */

.ab-cta {
  padding-top: clamp(3rem, 8vw, 6rem);
  padding-bottom: clamp(3rem, 8vw, 6rem);
  background:
    radial-gradient(120% 140% at 18% 0%, rgba(176, 141, 87, 0.24) 0%, rgba(176, 141, 87, 0) 60%),
    var(--nn-green-deep);
  color: var(--nn-paper);
}

.ab-cta__inner {
  display: grid;
  gap: clamp(1.6rem, 4vw, 2.6rem);
}

.ab-cta__title {
  margin: 0;
  font-family: var(--nn-font-display);
  font-weight: 400;
  color: var(--nn-paper);
}

.ab-cta__body {
  margin: 1rem 0 0;
  max-width: 58ch;
  font-size: 0.98rem;
  line-height: 1.95;
  color: var(--ab-paper-soft);
}

.ab-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
}

.ab-cta__ghost {
  background: transparent;
  color: var(--nn-gold-soft);
  border: 1px solid var(--ab-gold-line);
}

.ab-cta__ghost:hover {
  background: rgba(176, 141, 87, 0.12);
  color: var(--nn-paper);
}

/* ---------- 响应式 ---------- */

@media (min-width: 760px) {
  .ab-pillar {
    grid-template-columns: minmax(0, 130px) minmax(0, 1fr);
    gap: clamp(1.4rem, 4vw, 3rem);
    align-items: start;
  }

  .ab-pillars__head {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: end;
    gap: clamp(2rem, 5vw, 4rem);
  }

  .ab-timeline__top {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.62fr);
    align-items: end;
    gap: clamp(2rem, 5vw, 4rem);
  }

  .ab-timeline__media {
    max-width: 320px;
    justify-self: end;
  }

  .ab-cta__inner {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.6fr);
    align-items: end;
    gap: clamp(2rem, 5vw, 4rem);
  }

  .ab-cta__actions {
    justify-content: flex-end;
  }
}

@media (min-width: 900px) {
  .ab-origin__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
    gap: clamp(2.4rem, 5vw, 4rem);
  }

  .ab-origin__media {
    margin-top: clamp(2rem, 4vw, 3.2rem);
  }

  .ab-yunnan__grid {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
    align-items: center;
    gap: clamp(2.4rem, 5vw, 4.2rem);
  }

  .ab-team__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
    gap: clamp(2.4rem, 5vw, 4rem);
  }

  .ab-track::before {
    left: 8px;
  }

  .ab-track__item {
    display: grid;
    grid-template-columns: 132px minmax(0, 1fr);
    column-gap: clamp(1.6rem, 3vw, 2.6rem);
    padding-left: 2.6rem;
  }

  .ab-track__stage {
    text-align: right;
    padding-top: 0.1rem;
  }

  .ab-track__card {
    margin-top: 0;
  }
}

@media (min-width: 1100px) {
  .ab-hero__title {
    max-width: 18ch;
  }

  .ab-track__item {
    grid-template-columns: 160px minmax(0, 1fr);
  }
}

@media (max-width: 420px) {
  .ab-hero__metrics {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .ab-metric__label {
    font-size: 0.66rem;
    letter-spacing: 0.1em;
  }

  .ab-cta__actions {
    flex-direction: column;
    align-items: stretch;
  }

  .ab-cta__actions .nn-btn {
    width: 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-track__card {
    transition: none;
  }
}