.page-about {
  --about-rail: 232px;
  --about-panel: rgba(23, 35, 63, 0.66);
  background: var(--ink);
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 34px 0 58px;
  background:
    radial-gradient(118% 88% at 86% 4%, rgba(245, 184, 75, 0.2), transparent 60%),
    linear-gradient(158deg, var(--indigo) 0%, var(--ink) 68%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: 8%;
  right: -18%;
  width: 60%;
  height: 84%;
  background: linear-gradient(142deg, rgba(53, 214, 200, 0.15), rgba(53, 214, 200, 0) 66%);
  transform: rotate(-8deg);
  pointer-events: none;
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 30px;
}

.page-about .about-hero__text > * + * {
  margin-top: 15px;
}

.page-about h1 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2rem, 6.6vw, 3.5rem);
  line-height: 1.16;
  letter-spacing: -0.012em;
  color: var(--paper);
}

.page-about .h1-glow {
  color: var(--lamp);
  text-shadow: 0 0 28px rgba(245, 184, 75, 0.42);
}

.page-about .lede {
  margin: 0;
  max-width: 48ch;
  font-size: 1rem;
  line-height: 1.88;
  color: rgba(246, 235, 220, 0.84);
}

.page-about .about-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 14px 26px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-fact {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 88px;
  padding-left: 12px;
  border-left: 2px solid rgba(245, 184, 75, 0.5);
}

.page-about .about-fact strong {
  font-family: var(--font-num);
  font-size: 1.55rem;
  line-height: 1.1;
  color: var(--lamp);
}

.page-about .about-fact span {
  font-size: 0.76rem;
  letter-spacing: 0.04em;
  color: var(--gray);
}

.page-about .about-hero__media {
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 20px 54px rgba(0, 0, 0, 0.48);
}

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

.page-about .about-hero__media img {
  aspect-ratio: 16 / 9;
}

.page-about .media__caption {
  margin: 10px 2px 0;
  font-size: 0.79rem;
  letter-spacing: 0.02em;
  color: var(--gray);
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 46px 0 76px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.04fr) minmax(0, 0.96fr);
    align-items: center;
    gap: 54px;
  }

  .page-about .about-hero__media {
    transform: translateY(12px) rotate(-1.2deg);
  }
}

/* ---------- 主体：侧栏 + 内容流 ---------- */
.page-about .about-layout {
  display: grid;
  gap: 32px;
  padding-top: 52px;
  padding-bottom: 78px;
}

.page-about .about-rail__cap {
  margin: 0 0 12px;
  font-family: var(--font-num);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  color: var(--gray);
}

.page-about .about-rail__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 7px 0 7px 12px;
  border-left: 2px solid rgba(168, 176, 189, 0.24);
  color: rgba(246, 235, 220, 0.7);
  font-size: 0.9rem;
  text-decoration: none;
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--glow);
  border-left-color: var(--lamp);
}

.page-about .about-rail__num {
  font-family: var(--font-num);
  font-size: 0.8rem;
  color: var(--lamp);
  opacity: 0.88;
}

.page-about .about-rail__lamp {
  margin-top: 26px;
  margin-left: 7px;
  width: 2px;
  height: 110px;
  background: linear-gradient(180deg, rgba(245, 184, 75, 0) 0%, rgba(245, 184, 75, 0.72) 48%, rgba(245, 184, 75, 0) 100%);
}

@media (min-width: 960px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 58px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 128px;
    align-self: start;
  }

  .page-about .about-rail__list {
    display: block;
  }

  .page-about .about-rail__item + .about-rail__item {
    margin-top: 4px;
  }

  .page-about .about-rail__link {
    padding: 9px 0 9px 14px;
  }
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  padding: 34px 0;
  border-top: 1px solid rgba(168, 176, 189, 0.16);
}

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

.page-about .about-section__head {
  display: flex;
  align-items: flex-start;
  gap: 15px;
  margin-bottom: 22px;
}

.page-about .about-section__num {
  flex: none;
  font-family: var(--font-num);
  font-size: clamp(2rem, 5.6vw, 3rem);
  line-height: 0.92;
  letter-spacing: -0.02em;
  color: var(--lamp);
  opacity: 0.9;
}

.page-about .about-section h2 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.35rem, 4.4vw, 1.95rem);
  line-height: 1.34;
  letter-spacing: -0.005em;
  color: var(--glow);
}

.page-about .about-section__body {
  display: grid;
  gap: 24px;
}

@media (min-width: 780px) {
  .page-about .about-section__body {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.85fr);
    align-items: start;
    gap: 34px;
  }
}

.page-about .prose p {
  margin: 0 0 14px;
  font-size: 1rem;
  line-height: 1.9;
  color: rgba(246, 235, 220, 0.84);
}

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

/* ---------- 旁注卡 ---------- */
.page-about .aside-card {
  padding: 20px 20px 18px;
  border-radius: var(--radius-sm);
  background: var(--about-panel);
  border: 1px solid rgba(168, 176, 189, 0.2);
  border-left: 3px solid var(--lamp);
}

.page-about .aside-card--lamp {
  border-left-color: var(--cyan);
  background: rgba(53, 214, 200, 0.08);
}

.page-about .aside-card__cap {
  margin: 0 0 10px;
  font-family: var(--font-num);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--lamp);
}

.page-about .aside-card__list {
  display: grid;
  gap: 9px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .aside-card__list li {
  position: relative;
  padding-left: 14px;
  font-size: 0.87rem;
  line-height: 1.72;
  color: rgba(246, 235, 220, 0.78);
  overflow-wrap: anywhere;
}

.page-about .aside-card__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.66em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--lamp);
  box-shadow: 0 0 8px rgba(245, 184, 75, 0.6);
}

/* ---------- 等级刻度 ---------- */
.page-about .tier-scale {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .tier-scale__item {
  padding: 18px 16px 16px;
  border-radius: var(--radius-sm);
  background: rgba(23, 35, 63, 0.55);
  border: 1px solid rgba(168, 176, 189, 0.16);
}

.page-about .tier-scale__dot {
  display: block;
  width: 9px;
  height: 9px;
  margin-bottom: 12px;
  border-radius: 50%;
  background: var(--lamp);
  box-shadow: 0 0 12px rgba(245, 184, 75, 0.72);
}

.page-about .tier-scale__name {
  display: block;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.05rem;
  color: var(--glow);
}

.page-about .tier-scale__hint {
  display: block;
  margin-top: 6px;
  font-size: 0.8rem;
  line-height: 1.66;
  color: var(--gray);
}

@media (min-width: 700px) {
  .page-about .tier-scale {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0;
  }

  .page-about .tier-scale__item {
    border-radius: 0;
    border-right-width: 0;
  }

  .page-about .tier-scale__item:first-child {
    border-radius: var(--radius-sm) 0 0 var(--radius-sm);
  }

  .page-about .tier-scale__item:last-child {
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    border-right-width: 1px;
  }
}

/* ---------- 章节配图 ---------- */
.page-about .about-media {
  margin: 30px 0 0;
  border-radius: var(--radius);
  overflow: hidden;
  background: linear-gradient(160deg, rgba(53, 214, 200, 0.08), rgba(53, 214, 200, 0) 72%);
}

.page-about .about-section__body .about-media {
  margin-top: 0;
}

/* ---------- 阶段时间轴 ---------- */
.page-about .milestones {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .milestone {
  position: relative;
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 15px;
  padding-bottom: 26px;
}

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

.page-about .milestone:not(:last-child)::before {
  content: "";
  position: absolute;
  left: 25px;
  top: 42px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, rgba(245, 184, 75, 0.55), rgba(245, 184, 75, 0.06));
}

.page-about .milestone__num {
  position: relative;
  z-index: 1;
  display: grid;
  place-items: center;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  border: 1px solid rgba(245, 184, 75, 0.55);
  background: rgba(11, 18, 32, 0.92);
  font-family: var(--font-num);
  font-size: 0.94rem;
  color: var(--lamp);
}

.page-about .milestone__body h3 {
  margin: 5px 0 8px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.08rem;
  line-height: 1.4;
  color: var(--glow);
}

.page-about .milestone__body p {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.86;
  color: rgba(246, 235, 220, 0.8);
}

/* ---------- 延伸入口 ---------- */
.page-about .about-more {
  margin-top: 34px;
  padding: 28px 22px;
  border-radius: var(--radius);
  border: 1px solid rgba(168, 176, 189, 0.18);
  background:
    radial-gradient(120% 130% at 100% 0%, rgba(53, 214, 200, 0.14), transparent 62%),
    linear-gradient(160deg, rgba(23, 35, 63, 0.92), rgba(11, 18, 32, 0.92));
}

.page-about .about-more h2 {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.25rem, 4vw, 1.6rem);
  line-height: 1.38;
  color: var(--glow);
}

.page-about .about-more p {
  margin: 0 0 18px;
  font-size: 0.94rem;
  line-height: 1.82;
  color: rgba(246, 235, 220, 0.78);
}

.page-about .about-more__list {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 640px) {
  .page-about .about-more__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px 28px;
  }
}

.page-about .link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 0;
  color: var(--lamp);
  font-size: 0.96rem;
  text-decoration: none;
  border-bottom: 1px solid rgba(245, 184, 75, 0.28);
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-about .link-arrow::after {
  content: "→";
  transition: transform 0.25s var(--ease);
}

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

.page-about .link-arrow:hover::after,
.page-about .link-arrow:focus-visible::after {
  transform: translateX(4px);
}

@media (min-width: 960px) {
  .page-about .about-more {
    margin-top: 40px;
    padding: 34px 32px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .link-arrow,
  .page-about .link-arrow::after {
    transition: none;
  }

  .page-about .about-hero__media {
    transform: none;
  }
}