.page-about {
  background: var(--pitch);
  color: var(--chalk);
  overflow-x: hidden;
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

/* ---------- 面包屑 ---------- */
.page-about .about-masthead {
  padding-top: clamp(20px, 3vw, 36px);
}

/* ---------- 开场 ---------- */
.page-about .about-intro {
  position: relative;
  padding: clamp(24px, 4.4vw, 54px) 0 clamp(40px, 7vw, 88px);
}

.page-about .about-intro::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 36%;
  height: 1px;
  background: linear-gradient(90deg, rgba(232, 255, 58, 0.4), rgba(232, 255, 58, 0) 64%);
  transform: rotate(-1.4deg);
  transform-origin: left center;
  pointer-events: none;
}

.page-about .about-intro__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(26px, 4.5vw, 46px);
  align-items: start;
}

.page-about .about-intro h1 {
  margin: 14px 0 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2.05rem, 6.4vw, 3.85rem);
  line-height: 1.03;
  letter-spacing: -0.015em;
  color: var(--chalk);
}

.page-about .about-intro__lede {
  margin: 20px 0 0;
  max-width: 48ch;
  font-size: clamp(0.98rem, 2.1vw, 1.1rem);
  line-height: 1.8;
  color: rgba(244, 247, 242, 0.8);
}

/* ---------- 章节跳转胶囊 ---------- */
.page-about .about-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 26px;
}

.page-about .about-jump .chapter-link {
  display: inline-block;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.03em;
  text-decoration: none;
  color: rgba(244, 247, 242, 0.72);
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.page-about .about-jump .chapter-link:hover,
.page-about .about-jump .chapter-link:focus-visible {
  background: var(--yellow);
  border-color: var(--yellow);
  color: var(--ink);
}

/* ---------- 媒体容器 ---------- */
.page-about .media {
  margin: 0;
}

.page-about .media__frame {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--stripe);
}

.page-about .media__frame--3x2 { aspect-ratio: 3 / 2; }
.page-about .media__frame--14x9 { aspect-ratio: 14 / 9; }
.page-about .media__frame--16x7 { aspect-ratio: 16 / 7; }

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

.page-about .media__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  line-height: 1.6;
  color: var(--fog);
}

/* ---------- 章节头 ---------- */
.page-about .about-head {
  display: grid;
  gap: clamp(10px, 2vw, 20px);
  margin-bottom: clamp(28px, 5vw, 52px);
}

.page-about .about-head__text {
  min-width: 0;
}

/* ---------- 时间轴 ---------- */
.page-about .about-era {
  padding: clamp(42px, 7vw, 86px) 0;
  border-top: 1px solid var(--line);
}

.page-about .era-track {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .era {
  position: relative;
  padding: 0 0 clamp(22px, 4vw, 32px) 22px;
  border-left: 1px solid var(--line);
  transition: border-color 0.25s ease;
}

.page-about .era__dot {
  position: absolute;
  left: -4.5px;
  top: 12px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--fog);
  transition: background 0.25s ease, box-shadow 0.25s ease;
}

.page-about .era__year {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.35rem, 4vw, 1.85rem);
  line-height: 1;
  letter-spacing: 0.02em;
  color: rgba(244, 247, 242, 0.5);
  transition: color 0.25s ease;
}

.page-about .era__title {
  margin: 8px 0 0;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.08rem, 2.6vw, 1.32rem);
  letter-spacing: 0.01em;
  color: var(--chalk);
}

.page-about .era__text {
  margin: 8px 0 0;
  max-width: 44ch;
  font-size: 0.94rem;
  line-height: 1.76;
  color: rgba(244, 247, 242, 0.7);
}

.page-about .era:hover,
.page-about .era:focus-within {
  border-left-color: var(--line-soft);
}

.page-about .era:hover .era__dot,
.page-about .era:focus-within .era__dot {
  background: var(--yellow);
  box-shadow: 0 0 0 5px rgba(232, 255, 58, 0.14);
}

.page-about .era:hover .era__year,
.page-about .era:focus-within .era__year {
  color: var(--yellow);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: clamp(42px, 7vw, 86px) 0;
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(19, 84, 63, 0.42), rgba(11, 61, 46, 0.04));
}

.page-about .about-team__grid {
  display: grid;
  gap: clamp(28px, 4.5vw, 48px);
}

.page-about .about-team__para {
  margin: 16px 0 0;
  max-width: 52ch;
  font-size: 0.98rem;
  line-height: 1.8;
  color: rgba(244, 247, 242, 0.8);
}

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

/* 环形图 */
.page-about .team-ring {
  position: relative;
  margin-top: clamp(26px, 4vw, 40px);
  max-width: 380px;
}

.page-about .ring {
  display: block;
  width: min(210px, 54vw);
  height: auto;
  margin: 0;
}

.page-about .ring__track {
  fill: none;
  stroke: rgba(244, 247, 242, 0.1);
  stroke-width: 13;
}

.page-about .ring__arc {
  fill: none;
  stroke-width: 13;
}

.page-about .ring__arc--data {
  stroke: var(--yellow);
  stroke-dasharray: 209.6 339.3;
}

.page-about .ring__arc--ops {
  stroke: var(--blue);
  stroke-dasharray: 129.8 339.3;
  stroke-dashoffset: -209.6;
}

.page-about .ring-total {
  position: absolute;
  top: 0;
  left: 0;
  width: min(210px, 54vw);
  aspect-ratio: 1 / 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  pointer-events: none;
}

.page-about .ring-total__num {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2rem, 5vw, 2.6rem);
  line-height: 1;
  color: var(--chalk);
}

.page-about .ring-total__unit {
  margin-top: 2px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--fog);
}

.page-about .ring-legend {
  list-style: none;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .ring-legend__item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 11px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(244, 247, 242, 0.03);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.page-about .ring-legend__item:hover {
  border-color: var(--line-soft);
  transform: translateX(2px);
}

.page-about .ring-legend__key {
  flex: 0 0 auto;
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.page-about .ring-legend__key--data { background: var(--yellow); }
.page-about .ring-legend__key--ops { background: var(--blue); }

.page-about .ring-legend__label {
  flex: 1 1 auto;
  min-width: 0;
  font-size: 0.88rem;
  color: rgba(244, 247, 242, 0.82);
}

.page-about .ring-legend__val {
  flex: 0 0 auto;
  font-size: 1rem;
  font-weight: 700;
  color: var(--chalk);
}

/* ---------- 评测 ---------- */
.page-about .about-reviews {
  padding: clamp(42px, 7vw, 86px) 0;
  border-top: 1px solid var(--line);
}

.page-about .score-grid {
  display: grid;
  gap: clamp(14px, 2.4vw, 20px);
}

.page-about .score {
  position: relative;
  padding: clamp(20px, 3vw, 28px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(27, 42, 36, 0.6);
  overflow: hidden;
  transition: transform 0.25s ease, border-color 0.25s ease;
}

.page-about .score::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: linear-gradient(90deg, var(--yellow), var(--blue));
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.35s ease;
}

.page-about .score:hover {
  transform: translateY(-3px);
  border-color: var(--line-strong);
}

.page-about .score:hover::before {
  transform: scaleX(1);
}

.page-about .score__key {
  display: block;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--yellow);
}

.page-about .score__body {
  margin: 12px 0 0;
  font-size: 0.94rem;
  line-height: 1.78;
  color: rgba(244, 247, 242, 0.8);
}

.page-about .about-reviews__note {
  margin: clamp(24px, 4vw, 36px) 0 0;
  max-width: 62ch;
  font-size: 0.92rem;
  line-height: 1.78;
  color: rgba(244, 247, 242, 0.62);
}

/* ---------- 数据合作 ---------- */
.page-about .about-network {
  padding: clamp(42px, 7vw, 86px) 0;
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(27, 42, 36, 0.75), rgba(11, 61, 46, 0.1));
}

.page-about .net-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--line);
  overflow: hidden;
}

.page-about .net-cell {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(18px, 3vw, 26px) clamp(14px, 2.4vw, 22px);
  background: var(--pitch);
}

.page-about .net-cell__num {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2rem, 6vw, 3rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--yellow);
}

.page-about .net-cell__unit {
  margin-left: 3px;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 500;
  color: rgba(232, 255, 58, 0.72);
}

.page-about .net-cell__label {
  font-size: 0.85rem;
  line-height: 1.6;
  color: rgba(244, 247, 242, 0.68);
}

.page-about .about-network__note {
  margin: clamp(22px, 4vw, 34px) 0 0;
  max-width: 62ch;
  font-size: 0.92rem;
  line-height: 1.78;
  color: rgba(244, 247, 242, 0.62);
}

/* ---------- 备案 ---------- */
.page-about .about-filing {
  padding: clamp(42px, 7vw, 86px) 0;
  border-top: 1px solid var(--line);
}

.page-about .filing-card {
  display: grid;
  gap: clamp(18px, 3vw, 30px);
  padding: clamp(22px, 3.6vw, 36px);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: rgba(19, 84, 63, 0.42);
}

.page-about .filing-card__k {
  display: block;
  margin-top: 16px;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--yellow);
}

.page-about .filing-card__k:first-child {
  margin-top: 0;
}

.page-about .filing-card__v {
  margin: 6px 0 0;
  font-size: 0.96rem;
  line-height: 1.7;
  color: rgba(244, 247, 242, 0.9);
  word-break: break-word;
}

.page-about .filing-card__v a {
  color: var(--chalk);
  text-decoration: none;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .filing-card__v a:hover {
  color: var(--yellow);
}

.page-about .filing-card .copy-btn {
  margin-left: 10px;
  padding: 3px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  color: var(--fog);
  cursor: pointer;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.page-about .filing-card .copy-btn:hover {
  color: var(--ink);
  background: var(--yellow);
  border-color: var(--yellow);
}

.page-about .filing-card .contact-note {
  margin: 18px 0 0;
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--fog);
}

.page-about .about-filing__note {
  margin: clamp(22px, 4vw, 34px) 0 0;
  font-size: 0.92rem;
  line-height: 1.78;
  color: rgba(244, 247, 242, 0.62);
}

/* ---------- 收束 ---------- */
.page-about .about-close {
  padding: clamp(38px, 6vw, 74px) 0 clamp(52px, 8vw, 96px);
  border-top: 1px solid var(--line);
}

.page-about .about-close__figure {
  margin: 0 0 clamp(28px, 4.5vw, 46px);
}

.page-about .about-close__body {
  display: grid;
  gap: 16px;
  max-width: 68ch;
}

.page-about .about-close__title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.65rem, 4.6vw, 2.55rem);
  line-height: 1.08;
  letter-spacing: -0.01em;
  color: var(--chalk);
}

.page-about .about-close__text {
  margin: 0;
  font-size: 0.98rem;
  line-height: 1.8;
  color: rgba(244, 247, 242, 0.76);
}

.page-about .about-close__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 6px;
}

/* ---------- 内链通用 ---------- */
.page-about .about-reviews__note a,
.page-about .about-network__note a,
.page-about .about-filing__note a {
  color: var(--yellow);
  text-decoration: none;
  border-bottom: 1px solid rgba(232, 255, 58, 0.36);
  transition: border-color 0.2s ease;
}

.page-about .about-reviews__note a:hover,
.page-about .about-network__note a:hover,
.page-about .about-filing__note a:hover {
  border-color: var(--yellow);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .net-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 820px) {
  .page-about .filing-card {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
  }

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

@media (min-width: 900px) {
  .page-about .about-intro__grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    gap: clamp(34px, 5vw, 70px);
  }

  .page-about .about-head {
    grid-template-columns: minmax(88px, 132px) minmax(0, 1fr);
    gap: clamp(20px, 3vw, 38px);
    align-items: start;
  }

  .page-about .era-track {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .era {
    padding: 0 clamp(14px, 1.8vw, 24px) 0 clamp(14px, 1.8vw, 20px);
  }

  .page-about .era__text {
    max-width: none;
    font-size: 0.9rem;
  }

  .page-about .score-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 960px) {
  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: clamp(34px, 5vw, 72px);
    align-items: start;
  }

  .page-about .about-team__figure {
    margin-top: clamp(28px, 5vw, 68px);
  }
}

@media (max-width: 520px) {
  .page-about .ring-total,
  .page-about .ring {
    width: min(180px, 62vw);
  }

  .page-about .about-close__links .btn {
    flex: 1 1 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .score,
  .page-about .era,
  .page-about .era__dot,
  .page-about .era__year,
  .page-about .ring-legend__item,
  .page-about .score::before {
    transition: none;
  }
}