.page-about {
  --about-rule: rgba(155, 167, 180, 0.20);
  --about-rule-strong: rgba(155, 167, 180, 0.38);
  --about-cyan-soft: rgba(51, 225, 210, 0.12);
  --about-ink-soft: #35505f;
  padding-bottom: 0;
}

/* ===== 面包屑 ===== */
.page-about .about-crumb {
  padding: 20px 0 0;
}
.page-about .crumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--silver);
}
.page-about .crumb__link {
  color: var(--silver);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}
.page-about .crumb__link:hover,
.page-about .crumb__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}
.page-about .crumb__sep {
  color: var(--silver-dim);
}
.page-about .crumb__item--now {
  color: var(--paper);
  font-weight: 600;
}

/* ===== 首屏 ===== */
.page-about .about-hero {
  padding: 30px 0 54px;
}
.page-about .about-hero__grid {
  display: grid;
  gap: 32px;
  grid-template-columns: minmax(0, 1fr);
}
.page-about .about-hero__title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(32px, 8.6vw, 60px);
  line-height: 1.05;
  letter-spacing: -0.01em;
  color: var(--paper);
  margin: 16px 0 0;
  max-width: 22ch;
}
.page-about .about-hero__text {
  margin: 20px 0 0;
  max-width: 64ch;
  color: var(--silver);
  font-size: 16px;
  line-height: 1.82;
}
.page-about .about-hero__meta {
  margin: 20px 0 0;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--silver-dim);
}

.page-about .about-board {
  background: var(--paper);
  color: var(--ink);
  border: 1px solid rgba(10, 22, 34, 0.08);
  border-radius: var(--r-lg);
  padding: 26px 24px 20px;
  box-shadow: var(--shadow-paper);
}
.page-about .about-board__label {
  margin: 0;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: #6b7c88;
}
.page-about .about-board__list {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
}
.page-about .about-board__row {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 13px 0;
  border-bottom: 1px solid rgba(10, 22, 34, 0.12);
}
.page-about .about-board__row:last-child {
  border-bottom: 0;
  padding-bottom: 4px;
}
.page-about .about-board__num {
  font-family: var(--font-num);
  font-weight: 700;
  font-size: 32px;
  line-height: 1;
  min-width: 60px;
  color: var(--ink);
  letter-spacing: -0.02em;
}
.page-about .about-board__num--orange {
  color: var(--orange);
}
.page-about .about-board__txt {
  font-size: 13.5px;
  line-height: 1.55;
  color: var(--about-ink-soft);
}

/* ===== 章节骨架 ===== */
.page-about .about-section {
  padding: 48px 0;
}
.page-about .about-section + .about-section {
  border-top: 1px solid var(--about-rule);
}
.page-about .about-section__grid {
  display: grid;
  gap: 26px;
  grid-template-columns: minmax(0, 1fr);
}
.page-about .about-section__idx {
  display: block;
  font-family: var(--font-num);
  font-weight: 700;
  font-size: 46px;
  line-height: 1;
  letter-spacing: -0.05em;
  color: var(--silver-dim);
}
.page-about .about-section__head::before {
  content: "";
  display: block;
  width: 56px;
  height: 1px;
  background: var(--cyan);
  margin-bottom: 18px;
}
.page-about .about-section__title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(24px, 6.4vw, 36px);
  line-height: 1.16;
  color: var(--paper);
  margin: 12px 0 0;
}
.page-about .about-section__desc {
  margin: 14px 0 0;
  color: var(--silver);
  font-size: 15px;
  line-height: 1.78;
}

/* ===== 图片 ===== */
.page-about .about-figure {
  margin: 0;
}
.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-md);
}
.page-about .about-figure--banner {
  margin-bottom: 30px;
}
.page-about .about-figure--banner img {
  aspect-ratio: 16 / 9;
}
.page-about .about-figure--side img {
  aspect-ratio: 3 / 2;
}

/* ===== 时间线 ===== */
.page-about .about-line {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .about-line::before {
  content: "";
  position: absolute;
  left: 11px;
  top: 12px;
  bottom: 22px;
  width: 1px;
  background: var(--about-rule-strong);
}
.page-about .about-line__item {
  position: relative;
  padding-left: 34px;
  margin-bottom: 8px;
}
.page-about .about-stage {
  display: block;
}
.page-about .about-stage__sum {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 4px 14px;
  padding: 2px 0 16px;
  cursor: pointer;
  list-style: none;
}
.page-about .about-stage__sum::-webkit-details-marker {
  display: none;
}
.page-about .about-stage__sum::marker {
  content: "";
}
.page-about .about-stage__sum:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 4px;
  border-radius: var(--r-sm);
}
.page-about .about-stage__dot {
  position: absolute;
  left: -28px;
  top: 6px;
  width: 12px;
  height: 12px;
  background: var(--ink);
  border: 1px solid var(--cyan);
  box-shadow: 0 0 0 4px var(--about-cyan-soft);
}
.page-about .about-stage__stage {
  grid-column: 1;
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}
.page-about .about-stage__name {
  grid-column: 1;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 20px;
  line-height: 1.32;
  color: var(--paper);
  transition: color 0.2s ease;
}
.page-about .about-stage__sum:hover .about-stage__name {
  color: var(--cyan);
}
.page-about .about-stage__cue {
  grid-column: 2;
  grid-row: 1 / 3;
  align-self: center;
  font-family: var(--font-num);
  font-size: 20px;
  line-height: 1;
  color: var(--silver-dim);
  transition: transform 0.25s ease, color 0.25s ease;
}
.page-about .about-stage[open] .about-stage__cue {
  transform: rotate(45deg);
  color: var(--orange);
}
.page-about .about-stage__body {
  padding: 0 0 22px;
}
.page-about .about-stage__body p {
  margin: 0;
  max-width: 66ch;
  color: var(--silver);
  font-size: 15px;
  line-height: 1.85;
}

/* ===== 四个小组 ===== */
.page-about .about-crews {
  display: grid;
  gap: 16px;
  grid-template-columns: minmax(0, 1fr);
}
.page-about .about-crew {
  background: var(--ink-2);
  border: 1px solid var(--about-rule);
  border-radius: var(--r-md);
  padding: 20px 18px;
  transition: border-color 0.25s ease, transform 0.25s ease, box-shadow 0.25s ease;
}
.page-about .about-crew:hover {
  border-color: rgba(51, 225, 210, 0.55);
  transform: translateY(-2px);
  box-shadow: var(--shadow-soft);
}
.page-about .about-crew__no {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--orange);
}
.page-about .about-crew__name {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 20px;
  line-height: 1.3;
  color: var(--paper);
}
.page-about .about-crew__desc {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: var(--silver);
}

/* ===== 内容来源 ===== */
.page-about .about-sources {
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .about-sources__item {
  border-top: 1px solid var(--about-rule);
  padding: 18px 0;
}
.page-about .about-sources__item:first-child {
  border-top: 0;
  padding-top: 0;
}
.page-about .about-sources__key {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--cyan);
}
.page-about .about-sources__val {
  margin: 9px 0 0;
  font-size: 14.5px;
  line-height: 1.82;
  color: var(--silver);
}

/* ===== 赛季节奏 ===== */
.page-about .about-season {
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .about-season__row {
  display: grid;
  gap: 8px;
  grid-template-columns: minmax(0, 1fr);
  padding: 18px 0;
  border-bottom: 1px solid var(--about-rule);
}
.page-about .about-season__phase {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 18px;
  color: var(--paper);
}
.page-about .about-season__what {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--silver);
}
.page-about .about-season__out {
  margin: 0;
  font-size: 15px;
  letter-spacing: 0.06em;
  color: var(--amber);
}
.page-about .about-season__foot {
  margin: 24px 0 0;
  padding: 18px 20px;
  background: var(--ink-3);
  border-radius: var(--r-md);
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--paper);
}

/* ===== 做事方式 ===== */
.page-about .about-code {
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .about-code__item {
  position: relative;
  padding: 20px 0 20px 54px;
  border-top: 1px solid var(--about-rule);
}
.page-about .about-code__item:first-child {
  border-top: 0;
  padding-top: 0;
}
.page-about .about-code__no {
  position: absolute;
  left: 0;
  top: 17px;
  font-size: 16px;
  letter-spacing: 0.04em;
  color: var(--orange);
}
.page-about .about-code__item:first-child .about-code__no {
  top: -3px;
}
.page-about .about-code__name {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 19px;
  line-height: 1.35;
  color: var(--paper);
}
.page-about .about-code__desc {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--silver);
}

/* ===== 底部指引 ===== */
.page-about .about-cta {
  padding: 20px 0 80px;
}
.page-about .about-cta__box {
  display: grid;
  gap: 24px;
  padding: 30px 24px;
  border: 1px solid var(--about-rule-strong);
  border-radius: var(--r-lg);
  background:
    linear-gradient(140deg, rgba(51, 225, 210, 0.10), rgba(255, 106, 43, 0.07) 58%, rgba(10, 22, 34, 0) 100%),
    var(--ink-2);
}
.page-about .about-cta__title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(22px, 5.6vw, 30px);
  line-height: 1.2;
  color: var(--paper);
}
.page-about .about-cta__desc {
  margin: 12px 0 0;
  max-width: 60ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--silver);
}
.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.page-about .about-cta__links .btn {
  text-decoration: none;
}

/* ===== 桌面端 ===== */
@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 42px 0 66px;
  }
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.86fr);
    gap: 48px;
    align-items: start;
  }
  .page-about .about-board {
    margin-top: 8px;
    padding: 30px 28px 24px;
  }
  .page-about .about-board__num {
    font-size: 38px;
    min-width: 70px;
  }
  .page-about .about-crews {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 980px) {
  .page-about .about-section {
    padding: 62px 0;
  }
  .page-about .about-section__grid {
    grid-template-columns: minmax(240px, 320px) minmax(0, 1fr);
    gap: 52px;
    align-items: start;
  }
  .page-about .about-section__head {
    position: sticky;
    top: calc(var(--head-h) + 30px);
  }

  .page-about .about-section__body--split {
    display: grid;
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
    gap: 34px;
    align-items: start;
  }
  .page-about .about-section__body--flip {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.3fr);
  }

  .page-about .about-line__item + .about-line__item {
    margin-top: 12px;
  }
  .page-about .about-stage__name {
    font-size: 23px;
  }

  .page-about .about-season__row {
    grid-template-columns: 132px minmax(0, 1fr) 108px;
    align-items: baseline;
    gap: 24px;
  }
  .page-about .about-season__out {
    text-align: right;
  }

  .page-about .about-cta__box {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: center;
    gap: 40px;
    padding: 42px 40px;
  }
  .page-about .about-cta__links {
    justify-content: flex-end;
  }
}

/* ===== 动效降级 ===== */
@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition: none !important;
    animation: none !important;
  }
  .page-about .about-crew:hover {
    transform: none;
  }
  .page-about .about-stage[open] .about-stage__cue {
    transform: none;
  }
}
<<<END>>>