.page-about {
  --about-toc-w: 176px;
  --about-glow: rgba(34, 211, 238, 0.16);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(26px, 5vw, 64px) 0 clamp(28px, 5vw, 56px);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -180px;
  right: -140px;
  width: 480px;
  height: 480px;
  background: radial-gradient(circle at center, var(--about-glow), transparent 68%);
  pointer-events: none;
}

.page-about .about-hero__kicker {
  position: relative;
  margin: 0 0 18px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-hero__title {
  position: relative;
  margin: 0 0 22px;
  max-width: 16ch;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(36px, 9.6vw, 92px);
  line-height: 0.98;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--cyan);
}

.page-about .about-hero__lead {
  position: relative;
  margin: 0 0 26px;
  max-width: 62ch;
  font-size: clamp(15px, 2.1vw, 17px);
  line-height: 1.8;
  color: var(--paper-2);
}

.page-about .about-hero__meta {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 14px;
  margin: 0 0 34px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--paper-2);
}

.page-about .about-hero__sep {
  flex: none;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--line);
}

.page-about .about-stats {
  position: relative;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column-reverse;
  gap: 10px;
  padding: 18px 16px 20px;
  background: var(--ink-900);
}

.page-about .about-stat dt,
.page-about .about-stat dd {
  margin: 0;
}

.page-about .about-stat__value {
  font-family: var(--font-mono);
  font-size: clamp(24px, 5.4vw, 36px);
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-stat__value span {
  margin-left: 2px;
  font-size: 0.52em;
  color: var(--cyan);
}

.page-about .about-stat__label {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--paper-2);
}

/* ---------- 主体网格 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  padding-top: clamp(30px, 5vw, 56px);
}

/* ---------- 章节索引 ---------- */
.page-about .about-toc {
  min-width: 0;
}

.page-about .about-toc__list {
  display: flex;
  gap: 20px;
  margin: 0;
  padding: 0 0 10px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  border-bottom: 1px solid var(--line);
}

.page-about .about-toc__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-toc__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 0;
  white-space: nowrap;
  font-size: 13px;
  color: var(--paper-2);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--cyan);
}

.page-about .about-toc__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

/* ---------- 章节 ---------- */
.page-about .about-flow {
  min-width: 0;
}

.page-about .about-section {
  position: relative;
  padding: clamp(28px, 4.4vw, 48px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-section:last-child {
  border-bottom: 0;
}

.page-about .about-section.is-active::before {
  content: "";
  position: absolute;
  left: -12px;
  top: clamp(28px, 4.4vw, 48px);
  bottom: clamp(28px, 4.4vw, 48px);
  width: 2px;
  background: var(--cyan);
}

.page-about .about-section__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 18px;
}

.page-about .about-section__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .about-section__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(23px, 4.4vw, 38px);
  line-height: 1.14;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-section__body {
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--paper-2);
}

.page-about .about-section__body p {
  margin: 0 0 16px;
}

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

.page-about .about-inline-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(34, 211, 238, 0.42);
  transition: border-color 0.2s ease;
}

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

/* ---------- 旁注 ---------- */
.page-about .about-note {
  margin: 24px 0 0;
  padding: 18px 20px;
  background: var(--paper);
  border-left: 3px solid var(--magenta);
}

.page-about .about-note p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--ink-800);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 26px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--line);
}

.page-about .about-figure--square img {
  max-width: 520px;
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--paper-2);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 26px 0 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-team__cell {
  padding: 20px 18px 22px;
  background: var(--ink-800);
}

.page-about .about-team__role {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--amber);
}

.page-about .about-team__size {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 34px;
  line-height: 1;
  color: var(--paper);
}

.page-about .about-team__desc {
  margin: 0;
  font-size: 13px;
  line-height: 1.75;
  color: var(--paper-2);
}

/* ---------- 赛事分级 ---------- */
.page-about .about-levels {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 18px 0 22px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-level {
  padding: 16px 14px 18px;
  background: var(--ink-900);
  border-top: 2px solid var(--line);
}

.page-about .about-level:nth-child(1) { border-top-color: var(--magenta); }
.page-about .about-level:nth-child(2) { border-top-color: var(--cyan); }
.page-about .about-level:nth-child(3) { border-top-color: var(--amber); }
.page-about .about-level:nth-child(4) { border-top-color: var(--mint); }

.page-about .about-level__name {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 18px;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .about-level__desc {
  margin: 0;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--paper-2);
}

/* ---------- 能力清单 ---------- */
.page-about .about-caps {
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .about-caps__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-caps__key {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .about-caps__val {
  font-size: 14px;
  line-height: 1.8;
  color: var(--paper-2);
}

/* ---------- 版本节点 ---------- */
.page-about .about-verse {
  margin: 22px 0 0;
  padding: 0 0 0 22px;
  list-style: none;
  border-left: 1px solid var(--line);
}

.page-about .about-verse__item {
  position: relative;
  padding-bottom: 22px;
}

.page-about .about-verse__item:last-child {
  padding-bottom: 0;
}

.page-about .about-verse__item::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 7px;
  width: 9px;
  height: 9px;
  background: var(--amber);
  transform: rotate(45deg);
}

.page-about .about-verse__stage {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--amber);
}

.page-about .about-verse__name {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 19px;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .about-verse__desc {
  margin: 0;
  max-width: 62ch;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--paper-2);
}

/* ---------- 合作标签 ---------- */
.page-about .about-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 22px 0 0;
}

.page-about .about-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  font-size: 12.5px;
  letter-spacing: 0.02em;
  color: var(--paper-2);
  background: var(--ink-800);
  border: 1px solid var(--line);
}

.page-about .about-tag__n {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--magenta);
}

/* ---------- 联系 ---------- */
.page-about .about-contact {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 22px 0 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-contact__row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 14px;
  padding: 15px 16px;
  background: var(--ink-900);
}

.page-about .about-contact__k {
  flex: 0 0 84px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--paper-2);
}

.page-about .about-contact__v {
  flex: 1 1 auto;
  min-width: 0;
  word-break: break-word;
  font-size: 14px;
  color: var(--paper);
}

.page-about .about-contact__v.mono {
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

.page-about .about-contact__copy {
  flex: none;
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

/* ---------- 中等屏幕 ---------- */
@media (min-width: 700px) {
  .page-about .about-team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .about-caps__item {
    grid-template-columns: 116px minmax(0, 1fr);
    gap: 22px;
    align-items: baseline;
  }
}

/* ---------- 桌面端 ---------- */
@media (min-width: 1024px) {
  .page-about .about-hero {
    padding-bottom: clamp(40px, 5vw, 64px);
  }

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

  .page-about .about-body {
    grid-template-columns: var(--about-toc-w) minmax(0, 1fr);
    gap: clamp(40px, 4vw, 64px);
    align-items: start;
  }

  .page-about .about-toc {
    position: sticky;
    top: calc(var(--topbar-h) + 24px);
  }

  .page-about .about-toc__list {
    flex-direction: column;
    gap: 0;
    padding-bottom: 0;
    overflow: visible;
    border-bottom: 0;
    border-left: 1px solid var(--line);
  }

  .page-about .about-toc__link {
    padding: 11px 0 11px 14px;
    white-space: normal;
    line-height: 1.45;
    border-bottom: 0;
    border-left: 2px solid transparent;
    margin-left: -1px;
  }

  .page-about .about-toc__link:hover,
  .page-about .about-toc__link:focus-visible {
    border-bottom-color: transparent;
    border-left-color: var(--cyan);
  }

  .page-about .about-section.is-active::before {
    left: -18px;
  }
}