.page-about {
  --about-card: rgba(28, 39, 64, 0.52);
  --about-text-soft: rgba(242, 239, 233, 0.76);
  --about-text-mute: rgba(242, 239, 233, 0.52);
  --about-rule: rgba(138, 147, 166, 0.18);
  background: var(--ink);
  color: var(--bone);
  font-family: var(--font-body);
  overflow-x: clip;
}

/* ---------- 开篇 ---------- */
.page-about .about-open {
  position: relative;
  padding: clamp(18px, 3vw, 32px) 0 clamp(34px, 5vw, 64px);
  border-bottom: 1px solid var(--about-rule);
  background:
    radial-gradient(115% 130% at 92% -10%, rgba(139, 92, 246, 0.16), transparent 58%),
    radial-gradient(90% 120% at 2% 0%, rgba(53, 224, 208, 0.12), transparent 62%),
    linear-gradient(180deg, var(--ink-2) 0%, var(--ink) 82%);
}

.page-about .about-crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 12.5px;
  letter-spacing: 0.05em;
  color: var(--about-text-mute);
}

.page-about .about-crumbs a {
  color: var(--about-text-mute);
  text-decoration: none;
  transition: color 0.2s var(--ease);
}

.page-about .about-crumbs a:hover {
  color: var(--cyan);
}

.page-about .about-crumbs .crumbs-sep {
  color: var(--stone);
  opacity: 0.7;
}

.page-about .about-open__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 48px);
  margin-top: clamp(20px, 3vw, 34px);
}

.page-about .about-open h1 {
  font-family: var(--font-display);
  font-size: clamp(31px, 5.2vw, 58px);
  line-height: 1.1;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin: 14px 0 20px;
  color: var(--bone);
}

.page-about .about-open__text {
  max-width: 60ch;
  margin: 0;
  font-size: clamp(15px, 1.15vw, 17.5px);
  line-height: 1.82;
  color: var(--about-text-soft);
}

.page-about .about-open__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

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

.page-about .about-figure {
  margin: 0;
  padding: 15px 15px 17px;
  background: var(--ink-2);
}

.page-about .about-figure__label {
  margin: 0 0 8px;
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--about-text-mute);
}

.page-about .about-figure__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(23px, 2.6vw, 30px);
  font-weight: 600;
  line-height: 1.12;
  color: var(--cyan);
  letter-spacing: 0.01em;
}

.page-about .about-figure__num span {
  display: inline-block;
  margin-left: 4px;
  font-family: var(--font-body);
  font-size: 11.5px;
  font-weight: 400;
  letter-spacing: 0.04em;
  color: var(--about-text-mute);
}

.page-about .about-figure--violet .about-figure__num { color: var(--violet); }
.page-about .about-figure--clay .about-figure__num { color: var(--clay); }
.page-about .about-figure--bone .about-figure__num { color: var(--bone); }

/* ---------- 轨道布局 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 46px);
  padding: clamp(30px, 4.5vw, 60px) 0 0;
}

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

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

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding: clamp(30px, 4.4vw, 56px) 0;
  border-top: 1px solid var(--about-rule);
  scroll-margin-top: 96px;
}

.page-about .about-chapter:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-chapter__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 12px;
  margin: 0 0 20px;
}

.page-about .about-chapter .chapter__num {
  flex-shrink: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  line-height: 1;
  padding: 4px 9px 5px;
  color: var(--cyan);
  border: 1px solid rgba(53, 224, 208, 0.34);
  border-radius: 999px;
}

.page-about .about-chapter .chapter__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(22px, 3vw, 35px);
  font-weight: 700;
  line-height: 1.26;
  letter-spacing: -0.012em;
  color: var(--bone);
}

.page-about .about-prose p {
  max-width: 64ch;
  margin: 0 0 15px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--about-text-soft);
}

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

.page-about .about-lede {
  max-width: 62ch;
  margin: 0 0 24px;
  padding-left: 15px;
  border-left: 2px solid rgba(53, 224, 208, 0.5);
  font-size: clamp(15px, 1.1vw, 17px);
  line-height: 1.8;
  color: rgba(242, 239, 233, 0.86);
}

.page-about .about-note {
  max-width: 62ch;
  margin: 18px 0 0;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--about-text-mute);
}

/* ---------- 四条内容线 ---------- */
.page-about .line-grid {
  list-style: none;
  margin: 0 0 clamp(24px, 3vw, 34px);
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .line-card {
  padding: 17px 18px 19px;
  border: 1px solid var(--line);
  border-left-width: 2px;
  border-left-style: solid;
  border-radius: var(--radius-m);
  background: var(--about-card);
  backdrop-filter: blur(6px);
}

.page-about .line-card--cyan { border-left-color: var(--cyan); }
.page-about .line-card--violet { border-left-color: var(--violet); }
.page-about .line-card--clay { border-left-color: var(--clay); }
.page-about .line-card--moss { border-left-color: var(--moss); }

.page-about .line-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 16.5px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--bone);
}

.page-about .line-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: var(--about-text-soft);
}

/* ---------- 图像 ---------- */
.page-about .about-media {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  overflow: hidden;
  background: var(--glass);
}

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

.page-about .about-media .media__caption {
  padding: 10px 14px 12px;
  border-top: 1px solid var(--about-rule);
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--about-text-mute);
}

/* ---------- 双栏段 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 32px);
}

/* ---------- 档案索引 ---------- */
.page-about .archive-index {
  margin-top: 22px;
  padding: 4px 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: rgba(19, 28, 46, 0.72);
}

.page-about .archive-index__row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding: 12px 15px;
  border-top: 1px solid var(--about-rule);
}

.page-about .archive-index__row:first-child {
  border-top: 0;
}

.page-about .archive-index__key {
  flex-shrink: 0;
  min-width: 42px;
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .archive-index__val {
  font-size: 13.5px;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--about-text-soft);
}

.page-about .archive-index .tag {
  font-size: 11px;
}

/* ---------- 流程步骤 ---------- */
.page-about .step-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .step {
  position: relative;
  padding: 0 0 24px 52px;
}

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

.page-about .step::before {
  content: "";
  position: absolute;
  left: 16px;
  top: 34px;
  bottom: 2px;
  width: 1px;
  background: linear-gradient(180deg, rgba(53, 224, 208, 0.38), rgba(53, 224, 208, 0.06));
}

.page-about .step:last-child::before {
  display: none;
}

.page-about .step__num {
  position: absolute;
  left: 0;
  top: 0;
  width: 33px;
  height: 33px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--cyan);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 12.5px;
  font-weight: 600;
}

.page-about .step__title {
  margin: 4px 0 6px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--bone);
}

.page-about .step__text {
  max-width: 60ch;
  margin: 0;
  font-size: 14.5px;
  line-height: 1.76;
  color: var(--about-text-soft);
}

.page-about .step__more {
  max-width: 60ch;
  margin: 6px 0 0;
  font-size: 13px;
  line-height: 1.72;
  color: var(--about-text-mute);
  transition: color 0.25s var(--ease);
}

.page-about .step:hover .step__more,
.page-about .step:focus-within .step__more {
  color: rgba(53, 224, 208, 0.86);
}

/* ---------- 团队 ---------- */
.page-about .about-team-text {
  min-width: 0;
}

.page-about .role-list {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-rule);
  border: 1px solid var(--about-rule);
  border-radius: var(--radius-m);
  overflow: hidden;
}

.page-about .role-list li {
  display: grid;
  grid-template-columns: 64px 46px minmax(0, 1fr);
  align-items: center;
  gap: 10px;
  padding: 12px 14px;
  background: var(--ink-2);
  font-size: 13.5px;
  line-height: 1.6;
}

.page-about .role-list__name {
  color: var(--bone);
  font-weight: 600;
  letter-spacing: 0.02em;
}

.page-about .role-list__num {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 600;
  color: var(--cyan);
}

.page-about .role-list__desc {
  color: var(--about-text-mute);
}

/* ---------- 呼吸区 ---------- */
.page-about .about-breathe {
  padding: clamp(44px, 9vw, 104px) 0;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-breathe__text {
  max-width: 26ch;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(23px, 3.4vw, 42px);
  font-weight: 700;
  line-height: 1.34;
  letter-spacing: -0.012em;
  color: var(--bone);
}

.page-about .about-breathe__text::first-line {
  color: var(--bone);
}

/* ---------- 时间轴 ---------- */
.page-about .about-chapter--timeline {
  border-top: 0;
  padding-top: 0;
}

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 8px;
  display: flex;
  gap: 0;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .tl-item {
  position: relative;
  flex: 1 0 172px;
  min-height: 152px;
  padding: 48px 20px 0 0;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  top: 27px;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--line-strong);
}

.page-about .tl-item:last-child::before {
  background: linear-gradient(90deg, var(--line-strong), transparent);
}

.page-about .tl-item::after {
  content: "";
  position: absolute;
  top: 22px;
  left: 0;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(53, 224, 208, 0.14);
}

.page-about .tl-year {
  position: absolute;
  top: 0;
  left: 0;
  font-family: var(--font-mono);
  font-size: 19px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--cyan);
}

.page-about .tl-title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 15.5px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--bone);
}

.page-about .tl-text {
  margin: 0;
  font-size: 13px;
  line-height: 1.72;
  color: var(--about-text-mute);
}

/* ---------- 合作 ---------- */
.page-about .partner-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-bottom: 22px;
}

.page-about .partner-card {
  padding: 17px 18px 19px;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: linear-gradient(158deg, rgba(139, 92, 246, 0.16), rgba(28, 39, 64, 0.5) 62%);
}

.page-about .partner-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  color: var(--bone);
}

.page-about .partner-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.76;
  color: var(--about-text-soft);
}

/* ---------- 结尾入口 ---------- */
.page-about .about-chapter--next {
  padding-bottom: clamp(44px, 7vw, 84px);
}

.page-about .about-next {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .next-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px 22px;
  border: 1px solid var(--line);
  border-top-width: 2px;
  border-top-style: solid;
  border-radius: var(--radius-m);
  background: var(--about-card);
  text-decoration: none;
  color: inherit;
  transition: border-color 0.22s var(--ease), transform 0.22s var(--ease), background 0.22s var(--ease);
}

.page-about .next-card--orange { border-top-color: var(--orange); }
.page-about .next-card--violet { border-top-color: var(--violet); }
.page-about .next-card--cyan { border-top-color: var(--cyan); }

.page-about .next-card:hover,
.page-about .next-card:focus-visible {
  border-color: rgba(53, 224, 208, 0.46);
  background: rgba(28, 39, 64, 0.78);
  transform: translateY(-3px);
}

.page-about .next-card__kicker {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--about-text-mute);
}

.page-about .next-card--orange .next-card__kicker { color: var(--orange); }
.page-about .next-card--violet .next-card__kicker { color: var(--violet); }
.page-about .next-card--cyan .next-card__kicker { color: var(--cyan); }

.page-about .next-card__title {
  font-family: var(--font-display);
  font-size: 16.5px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--bone);
}

.page-about .next-card__desc {
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--about-text-soft);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .line-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

@media (min-width: 820px) {
  .page-about .about-open__grid {
    grid-template-columns: minmax(0, 1.42fr) minmax(0, 0.82fr);
    align-items: end;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: start;
  }

  .page-about .about-split--rev {
    grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
  }
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: 188px minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 108px;
    padding-left: 16px;
    border-left: 1px solid var(--about-rule);
  }

  .page-about .about-rail .index-rail__label {
    margin: 0 0 14px;
    font-size: 11px;
    letter-spacing: 0.18em;
    color: var(--about-text-mute);
  }

  .page-about .about-rail .index-rail__link {
    display: flex;
    align-items: baseline;
    gap: 8px;
    padding: 7px 0;
    font-size: 13px;
    line-height: 1.5;
    color: var(--about-text-mute);
    text-decoration: none;
    transition: color 0.2s var(--ease);
  }

  .page-about .about-rail .index-rail__link:hover,
  .page-about .about-rail .index-rail__link[aria-current="true"] {
    color: var(--cyan);
  }

  .page-about .about-rail .index-rail__num {
    font-family: var(--font-mono);
    font-size: 11px;
    color: var(--stone);
  }

  .page-about .about-rail .index-rail__link[aria-current="true"] .index-rail__num {
    color: var(--cyan);
  }
}

@media (hover: none) {
  .page-about .next-card:hover {
    transform: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .next-card,
  .page-about .step__more,
  .page-about .about-crumbs a,
  .page-about .about-rail .index-rail__link {
    transition: none;
  }

  .page-about .next-card:hover,
  .page-about .next-card:focus-visible {
    transform: none;
  }
}