.page-about {
  --about-gap: clamp(56px, 8vw, 96px);
  color: var(--paper);
}

.page-about .section {
  margin-top: var(--about-gap);
}

/* ===== 页头 ===== */
.page-about .about-head {
  padding-top: clamp(18px, 4vw, 36px);
}

.page-about .about-head .page-head__title {
  max-width: 16em;
  margin-top: 14px;
  font-size: var(--fs-display);
  line-height: 1.06;
  letter-spacing: -0.03em;
}

.page-about .about-head .page-head__lead {
  max-width: 62ch;
  margin-top: 20px;
  color: var(--mist);
  line-height: 1.75;
}

.page-about .about-index {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 28px;
}

.page-about .about-index a {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 6px 16px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  font-size: 0.875rem;
  color: var(--mist);
  text-decoration: none;
  transition: color 160ms ease, border-color 160ms ease, background-color 160ms ease;
}

@media (hover: hover) {
  .page-about .about-index a:hover {
    color: var(--green);
    border-color: var(--green);
    background-color: rgba(61, 255, 136, 0.06);
  }
}

/* ===== 图片与说明 ===== */
.page-about .media__frame {
  border-radius: var(--r-lg);
  overflow: hidden;
  border: 1px solid var(--line);
}

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

.page-about .about-figcap {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--faint);
}

/* ===== 立场声明 ===== */
.page-about .about-stance {
  display: grid;
  gap: 28px;
  align-items: start;
}

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

@media (min-width: 900px) {
  .page-about .about-stance {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.85fr);
    gap: clamp(32px, 4vw, 64px);
    align-items: center;
  }
}

/* ===== 四条原则 ===== */
.page-about .about-list {
  display: grid;
  gap: 12px;
  margin-top: 32px;
}

.page-about .about-principle {
  background-color: var(--ink-900);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  transition: border-color 160ms ease, transform 160ms ease, box-shadow 160ms ease;
}

@media (hover: hover) {
  .page-about .about-principle:hover {
    border-color: var(--green);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lift);
  }
}

.page-about .about-principle[open] {
  border-color: var(--green);
}

.page-about .about-principle > summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 16px;
  padding: 20px 22px;
  cursor: pointer;
  list-style: none;
}

.page-about .about-principle > summary::-webkit-details-marker {
  display: none;
}

.page-about .about-principle__idx {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  letter-spacing: 0.08em;
  color: var(--green);
}

.page-about .about-principle__name {
  font-size: 1.0625rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-principle__sub {
  display: block;
  margin-top: 4px;
  font-size: 0.8125rem;
  font-weight: 400;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .about-principle__sign {
  position: relative;
  width: 22px;
  height: 22px;
  border: 1px solid var(--line);
  border-radius: 50%;
  flex: none;
}

.page-about .about-principle__sign::before,
.page-about .about-principle__sign::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 8px;
  height: 1.5px;
  background-color: var(--mist);
  transform: translate(-50%, -50%);
  transition: transform 220ms ease, opacity 220ms ease;
}

.page-about .about-principle__sign::after {
  transform: translate(-50%, -50%) rotate(90deg);
}

.page-about .about-principle[open] .about-principle__sign::after {
  transform: translate(-50%, -50%) rotate(0deg);
  opacity: 0;
}

.page-about .about-principle__body {
  border-top: 1px solid var(--line);
  padding: 18px 22px 22px;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ===== 团队分工 ===== */
.page-about .about-roles {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
  margin-top: 32px;
  padding: 0;
  list-style: none;
}

.page-about .about-role {
  padding: 22px;
  background-color: var(--ink-900);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  transition: transform 160ms ease, border-color 160ms ease, box-shadow 160ms ease;
}

@media (hover: hover) {
  .page-about .about-role:hover {
    transform: translateY(-2px);
    border-color: var(--green);
    box-shadow: var(--shadow-lift);
  }
}

.page-about .about-role__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  line-height: 1;
  text-align: left;
  color: var(--green);
}

.page-about .about-role__name {
  margin-top: 12px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-role__desc {
  margin-top: 10px;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-team__note {
  max-width: 68ch;
  margin-top: 20px;
  font-size: 0.8125rem;
  line-height: 1.7;
}

/* ===== 场馆分档 ===== */
.page-about .about-venues__figure {
  margin: 30px 0 0;
}

.page-about .about-spectrum {
  margin-top: 22px;
}

.page-about .about-spectrum svg {
  display: block;
  width: 100%;
  height: 44px;
}

.page-about .about-tiers {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
  margin-top: 22px;
  padding: 0;
  list-style: none;
}

.page-about .about-tier {
  padding: 18px 20px 20px;
  background-color: var(--ink-800);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  transition: border-color 160ms ease, transform 160ms ease;
}

@media (hover: hover) {
  .page-about .about-tier:hover {
    border-color: var(--green);
    transform: translateY(-2px);
  }
}

.page-about .about-tier__code {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  text-align: left;
  color: var(--faint);
}

.page-about .about-tier__name {
  display: block;
  margin-top: 10px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-tier__dot {
  display: inline-block;
  width: 9px;
  height: 9px;
  margin-right: 8px;
  border-radius: 50%;
  vertical-align: middle;
}

.page-about .about-tier__dot--turf { background-color: var(--green-2); }
.page-about .about-tier__dot--mix { background-color: var(--green); }
.page-about .about-tier__dot--art { background-color: var(--mist); }
.page-about .about-tier__dot--roof { background-color: var(--faint); }

.page-about .about-tier__note {
  margin-top: 10px;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist);
}

/* ===== 赛季跨度 ===== */
.page-about .about-axis {
  position: relative;
  display: grid;
  gap: 26px;
  margin-top: 36px;
  padding: 0 0 0 24px;
  list-style: none;
}

.page-about .about-axis::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background-color: var(--line);
}

.page-about .about-axis__stop {
  position: relative;
}

.page-about .about-axis__dot {
  position: absolute;
  left: -24px;
  top: 5px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background-color: var(--ink-950);
  border: 2px solid var(--line);
}

.page-about .about-axis__stop:last-child .about-axis__dot {
  background-color: var(--green);
  border-color: var(--green);
}

.page-about .about-axis__name {
  display: block;
  font-size: 1rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-axis__note {
  display: block;
  margin-top: 6px;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-span__note {
  max-width: 66ch;
  margin-top: 28px;
  font-size: 0.875rem;
  line-height: 1.75;
}

@media (min-width: 780px) {
  .page-about .about-axis {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px;
    padding: 36px 0 0;
  }

  .page-about .about-axis::before {
    left: 0;
    right: 0;
    top: 12px;
    bottom: auto;
    width: auto;
    height: 1px;
    background-image: linear-gradient(90deg, var(--green), var(--line) 55%, var(--line));
    background-color: transparent;
  }

  .page-about .about-axis__dot {
    left: 0;
    top: -30px;
  }
}

/* ===== 发展历程 ===== */
.page-about .about-history__figure {
  margin: 30px 0 0;
}

.page-about .about-history {
  position: relative;
  display: grid;
  gap: 26px;
  margin-top: 36px;
  padding: 0 0 0 26px;
  list-style: none;
}

.page-about .about-history::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background-image: linear-gradient(180deg, var(--green), var(--line) 45%, var(--line));
  background-color: transparent;
}

.page-about .about-history__item {
  position: relative;
}

.page-about .about-history__dot {
  position: absolute;
  left: -26px;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background-color: var(--ink-950);
  border: 2px solid var(--line);
}

.page-about .about-history__item:last-child .about-history__dot {
  background-color: var(--green);
  border-color: var(--green);
}

.page-about .about-history__stage {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-align: left;
  color: var(--green);
}

.page-about .about-history__title {
  margin-top: 6px;
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--paper);
}

.page-about .about-history__text {
  max-width: 66ch;
  margin-top: 8px;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-record {
  margin-top: 34px;
  padding: 22px 24px;
  background-color: var(--ink-900);
  border: 1px solid var(--line);
  border-left: 2px solid var(--green);
  border-radius: var(--r-md);
}

.page-about .about-record p {
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ===== 延伸阅读 ===== */
.page-about .about-next__list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 10px;
  margin-top: 26px;
  padding: 0;
  list-style: none;
}

.page-about .about-next__list a {
  display: block;
  padding: 18px 20px;
  background-color: var(--ink-900);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  font-size: 1rem;
  font-weight: 700;
  color: var(--paper);
  text-decoration: none;
  transition: border-color 160ms ease, transform 160ms ease, box-shadow 160ms ease;
}

@media (hover: hover) {
  .page-about .about-next__list a:hover {
    border-color: var(--green);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lift);
  }
}

.page-about .about-next__list span {
  display: block;
  margin-top: 6px;
  font-size: 0.8125rem;
  font-weight: 400;
  line-height: 1.65;
  color: var(--mist);
}

/* ===== 窄屏收口 ===== */
@media (max-width: 480px) {
  .page-about .about-principle > summary {
    grid-template-columns: auto minmax(0, 1fr);
    gap: 12px;
    padding: 18px;
  }

  .page-about .about-principle__sign {
    display: none;
  }

  .page-about .about-principle__body {
    padding: 16px 18px 20px;
  }

  .page-about .about-index a {
    font-size: 0.8125rem;
    padding: 5px 13px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-principle,
  .page-about .about-role,
  .page-about .about-tier,
  .page-about .about-index a,
  .page-about .about-next__list a,
  .page-about .about-principle__sign::before,
  .page-about .about-principle__sign::after {
    transition: none;
  }

  .page-about .about-principle:hover,
  .page-about .about-role:hover,
  .page-about .about-tier:hover,
  .page-about .about-next__list a:hover {
    transform: none;
  }
}