.page-about {
  --about-spine-x: 9px;
  --about-gutter: 32px;
  overflow-x: clip;
  padding-bottom: 24px;
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-block: 32px 48px;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -120px;
  top: 18%;
  width: 320px;
  height: 320px;
  border: 1px solid var(--turf-line);
  border-radius: 50%;
  opacity: 0.55;
  pointer-events: none;
  display: none;
}

.page-about .about-hero__title {
  margin: 18px 0 22px;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(2.75rem, 11vw, 8.5rem);
  line-height: 0.94;
  letter-spacing: 0.005em;
  color: var(--paper);
}

.page-about .about-hero__accent {
  font-weight: 700;
  color: var(--signal);
}

.page-about .about-hero__lede {
  max-width: 60ch;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--paper-muted);
}

.page-about .about-hero__index {
  display: grid;
  gap: 16px 12px;
  margin: 34px 0 0;
  padding-top: 20px;
  border-top: 1px solid var(--turf-line);
}

.page-about .about-hero__index-item dt {
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--paper-muted);
  text-transform: uppercase;
}

.page-about .about-hero__index-item dd {
  margin: 6px 0 0;
  font-size: 1.75rem;
  font-weight: 500;
  color: var(--score-white);
  letter-spacing: 0.02em;
}

/* ---------- 章节脊柱 ---------- */
.page-about .about-body {
  position: relative;
}

.page-about .about-body::before {
  content: "";
  position: absolute;
  left: var(--about-spine-x);
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(
    to bottom,
    transparent,
    var(--turf-line) 6%,
    var(--turf-line) 94%,
    transparent
  );
}

.page-about .about-chapter {
  position: relative;
  padding-left: var(--about-gutter);
  padding-block: 34px;
}

.page-about .about-chapter__num {
  position: absolute;
  left: calc(var(--about-spine-x) - 10px);
  top: 36px;
  display: grid;
  place-items: center;
  width: 21px;
  height: 21px;
  border-radius: 999px;
  border: 1px solid var(--turf-line);
  background: var(--ink-base);
  font-family: var(--font-mono);
  font-size: 9px;
  color: var(--paper-muted);
}

.page-about .about-chapter__head {
  margin-bottom: 20px;
}

.page-about .about-chapter__head .section-title {
  margin-top: 10px;
}

.page-about .about-chapter__body > .prose {
  margin-top: 0;
  margin-bottom: 1.1em;
}

.page-about .about-chapter__body > .prose:last-child {
  margin-bottom: 0;
}

/* ---------- 痛点列表 ---------- */
.page-about .about-pains {
  list-style: none;
  margin: 22px 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-pains li {
  padding: 16px 18px;
  background: var(--stand-deep);
  border-left: 2px solid var(--turf-line);
  font-size: 0.94rem;
  line-height: 1.7;
  color: var(--paper);
  border-radius: 0 var(--radius-s) var(--radius-s) 0;
  transition: border-color 200ms var(--ease), background-color 200ms var(--ease);
}

.page-about .about-pains li:hover {
  border-left-color: var(--signal);
  background: color-mix(in srgb, var(--stand-deep) 88%, var(--signal));
}

.page-about .about-pains__tag {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--signal);
}

/* ---------- 图片 ---------- */
.page-about .media {
  max-width: 100%;
  margin: 0;
}

.page-about .about-bleed {
  margin: 24px 0 26px;
}

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

/* ---------- 团队分工 ---------- */
.page-about .about-roles {
  display: grid;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-role {
  padding: 18px 16px 20px;
  background: var(--stand-deep);
  border: 1px solid var(--turf-line);
  border-radius: var(--radius-m);
  transition: border-color 200ms var(--ease), transform 200ms var(--ease);
}

.page-about .about-role:hover {
  border-color: var(--signal-dim);
}

.page-about .about-role__idx {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  color: var(--signal);
}

.page-about .about-role h3 {
  margin: 0 0 8px;
  font-size: 1.02rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .about-role p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--paper-muted);
}

/* ---------- 情报来源 ---------- */
.page-about .about-sources {
  margin-top: 8px;
  margin-bottom: 24px;
}

.page-about .about-source {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 2px 12px;
  padding: 20px 0;
  border-top: 1px solid var(--turf-line);
}

.page-about .about-source:last-child {
  border-bottom: 1px solid var(--turf-line);
}

.page-about .about-source__idx {
  grid-column: 1;
  grid-row: 1;
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--signal);
  letter-spacing: 0.08em;
}

.page-about .about-source h3 {
  grid-column: 2;
  margin: 0;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--paper);
}

.page-about .about-source p {
  grid-column: 2;
  margin: 6px 0 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--paper-muted);
}

.page-about .about-rhythm {
  padding: 20px 20px 22px;
  margin-bottom: 22px;
  background: linear-gradient(120deg, var(--stand-deep), rgba(255, 138, 61, 0.09));
  border-left: 2px solid var(--amber);
  border-radius: 0 var(--radius-m) var(--radius-m) 0;
}

.page-about .about-rhythm__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--score-white);
}

.page-about .about-rhythm p:last-child {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--paper);
}

/* ---------- 更正流程 ---------- */
.page-about .about-fix {
  list-style: none;
  counter-reset: fix;
  margin: 20px 0 24px;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .about-fix li {
  counter-increment: fix;
  position: relative;
  padding: 16px 0 16px 40px;
  border-bottom: 1px dashed var(--turf-line);
}

.page-about .about-fix li::before {
  content: counter(fix, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 18px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--amber);
  letter-spacing: 0.08em;
}

.page-about .about-fix h3 {
  margin: 0 0 6px;
  font-size: 1rem;
  font-weight: 600;
  color: var(--paper);
}

.page-about .about-fix p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--paper-muted);
}

/* ---------- 历程时间轴 ---------- */
.page-about .about-years {
  position: relative;
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .about-years::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background-image: repeating-linear-gradient(
    to bottom,
    var(--turf-line) 0 5px,
    transparent 5px 11px
  );
}

.page-about .about-year {
  position: relative;
  padding-left: 30px;
  padding-bottom: 26px;
}

.page-about .about-year__dot {
  position: absolute;
  left: 0;
  top: 9px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--signal);
  box-shadow: 0 0 0 4px rgba(75, 255, 196, 0.1);
  animation: aboutNodePulse 2.4s ease-in-out infinite;
}

.page-about .about-year__year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 1.35rem;
  font-weight: 500;
  line-height: 1.1;
  color: var(--signal);
  letter-spacing: 0.03em;
}

.page-about .about-year__title {
  margin: 6px 0 6px;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--paper);
}

.page-about .about-year__text {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--paper-muted);
}

.page-about .about-year__more {
  margin: 6px 0 0;
  overflow: hidden;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--paper-muted);
  border-left: 1px solid var(--turf-line);
  padding-left: 12px;
  max-height: none;
  opacity: 1;
}

.page-about .about-year--figure {
  padding-bottom: 30px;
}

.page-about .about-year--figure .media {
  border-radius: var(--radius-m);
  overflow: hidden;
}

/* ---------- 覆盖层级 ---------- */
.page-about .about-layers {
  list-style: none;
  display: grid;
  gap: 8px;
  margin: 22px 0 28px;
  padding: 0;
}

.page-about .about-layers li {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  border: 1px solid var(--turf-line);
  border-radius: 999px;
  font-size: 0.94rem;
  color: var(--paper);
  background: transparent;
  transition: border-color 200ms var(--ease), background-color 200ms var(--ease);
}

.page-about .about-layers li:hover {
  border-color: var(--signal-dim);
  background: var(--stand-deep);
}

.page-about .about-layers .num {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--signal);
}

/* ---------- 规模条带 ---------- */
.page-about .about-band {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px 14px;
  margin: 0 0 26px;
  padding: 26px 20px;
  background: var(--stand-deep);
  border: 1px solid var(--turf-line);
  border-radius: var(--radius-l);
}

.page-about .about-band .band__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}

.page-about .about-band .band__num {
  font-family: var(--font-mono);
  font-size: 1.85rem;
  font-weight: 500;
  line-height: 1;
  color: var(--score-white);
  font-variant-numeric: tabular-nums;
}

.page-about .about-band .band__label {
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--paper-muted);
}

/* ---------- 收尾 ---------- */
.page-about .about-closing {
  margin-top: 16px;
  padding-top: 36px;
  border-top: 1px solid var(--turf-line);
}

.page-about .about-closing__media {
  margin-bottom: 26px;
  border-radius: var(--radius-m);
  overflow: hidden;
}

.page-about .about-closing__text .section-title {
  margin: 0 0 14px;
}

.page-about .about-closing__text .prose {
  margin: 0 0 22px;
  max-width: 56ch;
}

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

/* ---------- 回到球队 ---------- */
.page-about .about-quick {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 20px;
  margin-top: 34px;
  padding: 16px 18px;
  background: var(--ink-base);
  border: 1px solid var(--turf-line);
  border-radius: var(--radius-m);
}

.page-about .about-quick__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--signal);
}

@keyframes aboutNodePulse {
  0%, 100% { box-shadow: 0 0 0 4px rgba(75, 255, 196, 0.1); }
  50% { box-shadow: 0 0 0 8px rgba(75, 255, 196, 0.03); }
}

/* ---------- 平板 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__index {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

  .page-about .about-band {
    padding: 30px 26px;
  }

  .page-about .about-band .band__num {
    font-size: 2.2rem;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about {
    --about-spine-x: 24px;
    --about-gutter: 96px;
  }

  .page-about .about-hero {
    padding-block: 56px 76px;
  }

  .page-about .about-hero::after {
    display: block;
  }

  .page-about .about-hero__lede {
    font-size: 1.05rem;
  }

  .page-about .about-chapter {
    padding-block: 52px;
  }

  .page-about .about-chapter__num {
    left: calc(var(--about-spine-x) - 12px);
    top: 54px;
    width: 25px;
    height: 25px;
    font-size: 10px;
  }

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

  .page-about .about-chapter#team .about-chapter__body,
  .page-about .about-chapter#years .about-chapter__body,
  .page-about .about-chapter#scale .about-chapter__body {
    max-width: none;
  }

  .page-about .about-chapter#team .about-chapter__body > .prose,
  .page-about .about-chapter#years .about-chapter__body > .prose,
  .page-about .about-chapter#scale .about-chapter__body > .prose {
    max-width: 62ch;
  }

  .page-about .about-bleed {
    margin: 30px 0 40px;
    width: calc(100% + 48px);
    margin-right: -48px;
  }

  .page-about .about-roles {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-sources {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0 28px;
  }

  .page-about .about-source {
    grid-template-columns: 1fr;
    gap: 6px;
    padding: 22px 0 24px;
  }

  .page-about .about-source__idx {
    grid-column: 1;
    grid-row: auto;
    padding-top: 0;
  }

  .page-about .about-source h3,
  .page-about .about-source p {
    grid-column: 1;
  }

  .page-about .about-source p {
    margin-top: 2px;
  }

  .page-about .about-layers {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-layers li {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
    border-radius: var(--radius-m);
    padding: 16px;
  }

  .page-about .about-band {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px 24px;
    padding: 34px 32px;
    margin-bottom: 34px;
  }

  .page-about .about-band .band__num {
    font-size: 2.6rem;
  }

  /* 时间轴左右错位 */
  .page-about .about-years {
    margin-top: 32px;
    padding-left: 8px;
  }

  .page-about .about-year {
    padding-left: 44px;
    padding-bottom: 34px;
    max-width: 58ch;
  }

  .page-about .about-year:nth-child(even):not(.about-year--figure) {
    margin-left: 96px;
  }

  .page-about .about-year--figure {
    padding-left: 44px;
    margin-left: 0;
    max-width: none;
    width: min(420px, 60%);
  }

  .page-about .about-year--figure .media {
    margin-left: -12px;
  }

  .page-about .about-year__more {
    max-height: 0;
    opacity: 0;
    margin-top: 0;
    transition: max-height 260ms var(--ease), opacity 200ms linear, margin-top 200ms var(--ease);
  }

  .page-about .about-year:hover .about-year__more,
  .page-about .about-year:focus-within .about-year__more {
    max-height: 10em;
    opacity: 1;
    margin-top: 8px;
  }

  .page-about .about-closing {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: 48px;
    align-items: center;
    margin-top: 40px;
    padding-top: 52px;
  }

  .page-about .about-closing__media {
    margin-bottom: 0;
    margin-left: -32px;
  }

  .page-about .about-quick {
    margin-top: 48px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-year__dot {
    animation: none;
  }
  .page-about .about-year__more {
    transition: none;
  }
}