.page-about {
  --about-line-soft: rgba(242, 245, 247, .14);
  --about-card: rgba(19, 35, 57, .66);
  display: block;
  color: var(--bone);
}

/* ============ 首屏 · 拼贴台面 ============ */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(18px, 3vw, 32px) 0 clamp(44px, 6vw, 84px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -12% -6% auto -6%;
  height: 130%;
  pointer-events: none;
  background:
    radial-gradient(42% 44% at 80% 6%, rgba(34, 227, 208, .16), transparent 62%),
    radial-gradient(38% 42% at 2% 94%, rgba(255, 138, 61, .14), transparent 66%);
}

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

.page-about .about-hero .crumbs {
  margin-bottom: clamp(20px, 3vw, 34px);
}

.page-about .about-hero__board {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3.6vw, 42px);
}

.page-about .about-hero__lead .tag {
  display: inline-block;
  margin-bottom: 16px;
}

.page-about .about-hero__lead h1 {
  margin: 0 0 18px;
}

.page-about .about-hero__lead .lede {
  max-width: 62ch;
  margin: 0;
}

.page-about .about-hero__panel {
  display: grid;
  gap: 12px;
}

.page-about .about-stat {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 14px 18px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--slate);
  border-radius: var(--radius-sm);
  background: linear-gradient(120deg, rgba(19, 35, 57, .92), rgba(10, 20, 36, .68));
}

.page-about .about-stat--cyan { border-left-color: var(--cyan); }
.page-about .about-stat--orange { border-left-color: var(--orange); }
.page-about .about-stat--clay { border-left-color: var(--clay); }

.page-about .about-stat__k {
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--slate);
  white-space: nowrap;
}

.page-about .about-stat__v {
  font-size: clamp(1.75rem, 5vw, 3rem);
  line-height: 1;
  color: var(--bone);
  display: inline-flex;
  align-items: baseline;
  gap: 4px;
}

.page-about .about-stat--cyan .about-stat__v { color: var(--cyan); }
.page-about .about-stat--orange .about-stat__v { color: var(--orange); }

.page-about .about-stat__u {
  font-size: 13px;
  color: var(--slate);
  letter-spacing: .04em;
}

/* ============ 01 起点 ============ */
.page-about .about-origin {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3.4vw, 40px);
  align-items: start;
}

.page-about .about-origin__text p {
  margin: 0 0 1.15em;
}

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

.page-about .about-plate {
  position: relative;
  padding: 24px 22px 26px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background: linear-gradient(158deg, rgba(201, 123, 90, .16), rgba(10, 20, 36, .62));
}

.page-about .about-plate::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 26px;
  width: 3px;
  height: 46px;
  border-radius: 0 3px 3px 0;
  background: var(--clay);
}

.page-about .about-plate__k {
  display: block;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--clay);
}

.page-about .about-plate__v {
  display: block;
  margin: 6px 0 14px;
  font-size: clamp(2.2rem, 6vw, 3rem);
  line-height: 1;
  color: var(--bone);
}

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

.page-about .about-plate__list li {
  position: relative;
  padding-left: 18px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--bone);
}

.page-about .about-plate__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 7px;
  height: 7px;
  border-radius: 2px;
  background: var(--cyan);
  transform: rotate(45deg);
}

.page-about .about-plate__note {
  margin: 16px 0 0;
  padding-top: 14px;
  border-top: 1px dashed var(--about-line-soft);
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
}

/* ============ 02 时间线 ============ */
.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 clamp(28px, 4vw, 46px) 30px;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), rgba(255, 138, 61, .45) 65%, rgba(242, 245, 247, .08));
  opacity: .55;
}

.page-about .about-timeline__item::after {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--cyan);
  box-shadow: 0 0 0 4px rgba(34, 227, 208, .1);
}

.page-about .about-timeline__item:last-child::before {
  bottom: auto;
  height: 30px;
}

.page-about .about-timeline__item:focus {
  outline: none;
}

.page-about .about-timeline__item:focus-visible .about-timeline__title {
  color: var(--cyan);
}

.page-about .about-timeline__mark {
  display: inline-block;
  margin-bottom: 10px;
  padding: 3px 12px;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--cyan);
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--glass);
}

.page-about .about-timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-size: clamp(1.15rem, 2.4vw, 1.5rem);
  font-weight: 700;
  line-height: 1.45;
  color: var(--bone);
  transition: color .24s var(--ease-out);
}

.page-about .about-timeline__text {
  margin: 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.9;
  color: rgba(242, 245, 247, .82);
}

.page-about .about-timeline__note {
  margin: 0 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--clay);
  font-size: 14px;
  line-height: 1.8;
  color: var(--slate);
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height .36s var(--ease-out), opacity .26s var(--ease-out), margin-top .26s var(--ease-out);
}

@media (hover: hover) and (pointer: fine) {
  .page-about .about-timeline__item:hover .about-timeline__note,
  .page-about .about-timeline__item:focus-within .about-timeline__note,
  .page-about .about-timeline__item:focus .about-timeline__note {
    max-height: 140px;
    opacity: 1;
    margin-top: 12px;
  }

  .page-about .about-timeline__item:hover::after {
    border-color: var(--orange);
    box-shadow: 0 0 0 4px rgba(255, 138, 61, .12);
  }
}

@media (hover: none), (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__note {
    max-height: none;
    opacity: 1;
    margin-top: 12px;
  }
}

/* ============ 03 规则校对 ============ */
.page-about .about-rules {
  position: relative;
}

.page-about .about-rules .section__num {
  color: var(--orange);
}

.page-about .about-rules__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3.6vw, 46px);
  align-items: start;
}

.page-about .about-rules__figure {
  margin: 0;
}

.page-about .about-rules__body p {
  margin: 0 0 1.1em;
}

.page-about .about-rules__list {
  margin-top: clamp(18px, 2.4vw, 26px);
  padding: 20px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(150deg, rgba(255, 138, 61, .1), rgba(10, 20, 36, .5));
}

.page-about .about-rules__list .rule-list__item {
  color: rgba(242, 245, 247, .86);
  line-height: 1.9;
}

/* ============ 04 两支队伍 ============ */
.page-about .about-teams-section .section__num {
  color: var(--clay);
}

.page-about .about-teams__figure {
  margin: 0 0 clamp(26px, 3.6vw, 44px);
}

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

.page-about .about-teams .accordion__trigger {
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  text-align: left;
}

.page-about .about-teams__label {
  font-family: var(--font-serif);
  font-size: clamp(1.05rem, 2.2vw, 1.35rem);
  font-weight: 700;
  color: var(--bone);
}

.page-about .about-teams__value {
  margin-left: auto;
  font-size: clamp(1.6rem, 4.4vw, 2.1rem);
  line-height: 1;
  color: var(--cyan);
  letter-spacing: .02em;
}

.page-about .about-teams .accordion__panelInner p {
  margin: 0 0 1em;
  line-height: 1.9;
}

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

/* ============ 05 合作生态 ============ */
.page-about .about-partners {
  list-style: none;
  margin: 0 0 clamp(26px, 3.6vw, 42px);
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(16px, 2.4vw, 26px);
}

.page-about .about-partners__item {
  position: relative;
  padding: 26px 24px 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(140deg, rgba(19, 35, 57, .92), rgba(10, 20, 36, .72));
  overflow: hidden;
}

.page-about .about-partners__item::after {
  content: "";
  position: absolute;
  right: -40px;
  bottom: -40px;
  width: 140px;
  height: 140px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(34, 227, 208, .16), transparent 70%);
  pointer-events: none;
}

.page-about .about-partners__item--narrow::after {
  background: radial-gradient(circle, rgba(201, 123, 90, .2), transparent 70%);
}

.page-about .about-partners__num {
  display: block;
  margin: 16px 0 10px;
  font-size: clamp(2.6rem, 8vw, 3.6rem);
  line-height: 1;
  color: var(--bone);
  letter-spacing: -.01em;
}

.page-about .about-partners__num-u {
  margin-left: 6px;
  font-size: 14px;
  color: var(--slate);
}

.page-about .about-partners__title {
  margin: 0 0 10px;
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--bone);
}

.page-about .about-partners__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.9;
  color: rgba(242, 245, 247, .8);
}

.page-about .about-partners__figure {
  margin: 0;
}

/* ============ 06 下一步 ============ */
.page-about .about-next {
  padding-bottom: clamp(56px, 8vw, 104px);
}

.page-about .about-next__inner {
  position: relative;
  padding: clamp(28px, 4.4vw, 52px) clamp(22px, 3.6vw, 48px);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  background:
    radial-gradient(80% 120% at 100% 0%, rgba(255, 138, 61, .16), transparent 62%),
    linear-gradient(150deg, rgba(19, 35, 57, .95), rgba(10, 20, 36, .8));
}

.page-about .about-next__inner .section__num {
  color: var(--orange);
}

.page-about .about-next__inner .section__title {
  margin-top: 8px;
}

.page-about .about-next__text {
  max-width: 68ch;
  margin: 0 0 clamp(20px, 3vw, 30px);
}

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

/* ============ 图片容器 ============ */
.page-about .figure__media {
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: linear-gradient(135deg, var(--ink-raise), var(--ink-deep));
}

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

.page-about .figure__cap {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate);
}

/* ============ 响应式 ============ */
@media (min-width: 720px) {
  .page-about .about-partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-partners__item--wide {
    grid-column: span 2;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__board {
    grid-template-columns: minmax(0, 1.45fr) minmax(268px, .8fr);
    align-items: start;
  }

  .page-about .about-origin {
    grid-template-columns: minmax(0, 1.1fr) minmax(260px, .9fr);
  }

  .page-about .about-rules__grid {
    grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
  }

  .page-about .about-rules__figure {
    position: sticky;
    top: calc(var(--header-h) + 28px);
  }

  .page-about .about-teams .accordion__trigger {
    gap: 22px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-timeline__item--w1 { width: 84%; }
  .page-about .about-timeline__item--w2 { width: 100%; }
  .page-about .about-timeline__item--w3 { width: 72%; }
  .page-about .about-timeline__item--w4 { width: 92%; }
  .page-about .about-timeline__item--w5 { width: 78%; }
  .page-about .about-timeline__item--w6 { width: 96%; }

  .page-about .about-partners {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, .75fr);
    align-items: start;
  }

  .page-about .about-partners__item--wide {
    grid-column: auto;
  }
}

@media (max-width: 520px) {
  .page-about .about-stat {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .page-about .about-next__links .btn {
    width: 100%;
    text-align: center;
  }
}