.page-about {
  --about-narrow: 680px;
  --about-head-col: 240px;
  --about-num-ink: rgba(11, 110, 143, 0.16);
  overflow-x: clip;
  padding-bottom: clamp(48px, 8vw, 96px);
}

.page-about .about-wrap {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 20px var(--pad) 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 18px;
  margin-top: 20px;
}

.page-about .about-hero-main {
  position: relative;
  overflow: hidden;
  padding: clamp(30px, 8vw, 52px) clamp(22px, 6vw, 48px);
  border-radius: var(--r-lg);
  background: linear-gradient(128deg, var(--c-deep) 0%, var(--c-lake) 84%);
  color: var(--c-snow);
}

.page-about .about-hero-main::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(120% 95% at 100% 0%, rgba(217, 162, 39, 0.3), transparent 58%);
  pointer-events: none;
}

.page-about .about-hero-main::after {
  content: "";
  position: absolute;
  right: -84px;
  top: -64px;
  width: 260px;
  height: 260px;
  transform: rotate(18deg);
  border-radius: 42% 58% 60% 40% / 46% 40% 60% 54%;
  background: linear-gradient(150deg, rgba(251, 252, 253, 0.16), transparent 70%);
  pointer-events: none;
}

.page-about .about-eyebrow {
  position: relative;
  z-index: 1;
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  color: rgba(251, 252, 253, 0.7);
}

.page-about .about-title {
  position: relative;
  z-index: 1;
  margin: 0;
  max-width: 15em;
  color: var(--c-snow);
  font-family: var(--font-head);
  font-size: clamp(1.75rem, 5.2vw, 2.5rem);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.02em;
}

.page-about .about-hero-aside {
  padding: clamp(22px, 5vw, 36px);
  border-radius: var(--r-lg);
  background: var(--c-snow);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-card);
}

.page-about .about-lede {
  margin: 0 0 18px;
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--ink-80);
}

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

.page-about .about-facts li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: var(--fs-14);
  line-height: 1.7;
  color: var(--ink-60);
}

.page-about .about-facts li::before {
  content: "";
  flex: 0 0 auto;
  width: 8px;
  height: 8px;
  margin-top: 8px;
  border-radius: 50%;
  background: var(--c-gold);
}

/* ---------- 章节目录 ---------- */
.page-about .about-toc {
  position: sticky;
  top: 80px;
  z-index: 4;
  margin: 26px 0 6px;
  padding: 10px 12px;
  border-radius: var(--r-pill);
  background: rgba(251, 252, 253, 0.92);
  border: 1px solid var(--line-soft);
  box-shadow: var(--shadow-pill);
  backdrop-filter: blur(10px);
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

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

.page-about .about-toc-list {
  display: flex;
  gap: 6px;
  width: max-content;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-toc-link {
  display: block;
  padding: 8px 16px;
  border-radius: var(--r-pill);
  font-size: var(--fs-13);
  color: var(--ink-60);
  white-space: nowrap;
  text-decoration: none;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .about-toc-link:hover {
  background: var(--c-mist);
  color: var(--c-deep);
}

.page-about .about-toc-link[aria-current="true"] {
  background: var(--c-red);
  color: var(--c-snow);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-sections {
  margin-top: 6px;
}

.page-about .about-section {
  padding: clamp(40px, 7vw, 76px) 0;
  border-top: 1px solid var(--line-soft);
  scroll-margin-top: 150px;
}

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

.page-about .about-section-head {
  margin-bottom: 20px;
}

.page-about .about-section-head .section-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(2.4rem, 7vw, 3.5rem);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--about-num-ink);
}

.page-about .about-section-head h2 {
  margin: 8px 0 0;
  font-family: var(--font-head);
  font-size: var(--fs-24);
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.02em;
  color: var(--c-ink);
}

.page-about .about-section-body {
  display: grid;
  gap: 22px;
}

.page-about .about-body {
  display: grid;
  gap: 14px;
  max-width: var(--about-narrow);
}

.page-about .about-body p {
  margin: 0;
  font-size: var(--fs-16);
  line-height: 1.8;
  color: var(--ink-80);
}

.page-about .about-scroll-hint {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--ink-40);
}

.page-about .about-inline-link {
  color: var(--c-lake);
  text-decoration: underline;
  text-decoration-color: rgba(11, 110, 143, 0.35);
  text-underline-offset: 4px;
  transition: color var(--dur) var(--ease), text-decoration-color var(--dur) var(--ease);
}

.page-about .about-inline-link:hover {
  color: var(--c-red);
  text-decoration-color: var(--c-red);
}

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

.page-about .about-figure .figure-media {
  border-radius: var(--r-card);
  overflow: hidden;
  border: 1px solid var(--line-soft);
  background: var(--c-mist);
}

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

.page-about .about-figure-flow .figure-media img {
  object-position: center;
}

/* ---------- 01 角色卡 ---------- */
.page-about .about-roles {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-roles li {
  padding: 18px 20px;
  border-radius: var(--r-card);
  background: var(--c-mist);
  border: 1px solid transparent;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-roles li:hover {
  background: var(--c-snow);
  border-color: var(--c-wine);
  transform: translateY(-3px);
}

.page-about .about-roles h3 {
  margin: 0 0 6px;
  font-size: var(--fs-14);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--c-deep);
}

.page-about .about-roles p {
  margin: 0;
  font-size: var(--fs-13);
  line-height: 1.75;
  color: var(--ink-60);
}

/* ---------- 02 三轮校对 ---------- */
.page-about .about-steps {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-step {
  position: relative;
  padding: 22px 20px 20px;
  border-radius: var(--r-card);
  background: var(--c-snow);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-card);
  outline-offset: 4px;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-step:hover,
.page-about .about-step:focus-visible {
  transform: translateY(-4px);
  border-color: var(--c-wine);
}

.page-about .about-step::after {
  content: "";
  position: absolute;
  left: 20px;
  right: 20px;
  bottom: -1px;
  height: 3px;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--c-lake), var(--c-gold));
  opacity: 0;
  transition: opacity var(--dur) var(--ease);
}

.page-about .about-step:hover::after,
.page-about .about-step:focus-visible::after {
  opacity: 1;
}

.page-about .about-step-no {
  display: inline-block;
  margin-bottom: 10px;
  font-size: var(--fs-12);
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--c-gold);
}

.page-about .about-step h3 {
  margin: 0 0 8px;
  font-size: var(--fs-18);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--c-ink);
}

.page-about .about-step p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--ink-60);
}

.page-about .about-step .about-step-more {
  max-height: 200px;
  overflow: hidden;
  opacity: 1;
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px dashed var(--line);
  font-size: var(--fs-13);
  color: var(--ink-40);
  transition: max-height var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

/* ---------- 03 发布节奏 ---------- */
.page-about .about-cadence {
  display: grid;
  gap: 16px;
}

.page-about .about-cadence-card {
  position: relative;
  overflow: hidden;
  padding: 26px 24px 24px 28px;
  border-radius: var(--r-card);
  background: var(--c-snow);
  border: 1px solid var(--line);
}

.page-about .about-cadence-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 5px;
  height: 100%;
  background: linear-gradient(180deg, var(--c-lake), var(--c-deep));
}

.page-about .about-cadence-weekly::before {
  background: linear-gradient(180deg, var(--c-red), var(--c-wine));
}

.page-about .about-cadence-monthly::before {
  background: linear-gradient(180deg, var(--c-gold), var(--c-lake));
}

.page-about .about-cadence-card h3 {
  margin: 14px 0 10px;
  font-size: var(--fs-18);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--c-ink);
}

.page-about .about-cadence-card p {
  margin: 0 0 8px;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--ink-60);
}

.page-about .about-cadence-card p:last-child {
  margin-bottom: 0;
  color: var(--ink-40);
  font-size: var(--fs-13);
}

/* ---------- 04 时间线 ---------- */
.page-about .about-timeline {
  overflow-x: auto;
  padding: 6px 2px 20px;
  scroll-snap-type: x mandatory;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-timeline-list {
  display: flex;
  gap: 16px;
  width: max-content;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-timeline-item {
  position: relative;
  flex: 0 0 auto;
  width: min(74vw, 280px);
  padding: 24px 22px 22px;
  border-radius: var(--r-card);
  background: var(--c-snow);
  border: 1px solid var(--line);
  scroll-snap-align: start;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .about-timeline-item:hover {
  transform: translateY(-4px);
  border-color: var(--c-wine);
  box-shadow: var(--shadow-card);
}

.page-about .about-node {
  position: absolute;
  top: 26px;
  left: 22px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--c-gold);
  box-shadow: 0 0 0 5px rgba(217, 162, 39, 0.16);
}

.page-about .about-timeline-year {
  display: block;
  margin: 0 0 8px 24px;
  font-size: var(--fs-24);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--c-deep);
}

.page-about .about-timeline-title {
  margin: 0 0 8px;
  font-size: var(--fs-16);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--c-ink);
}

.page-about .about-timeline-item p {
  margin: 0;
  font-size: var(--fs-13);
  line-height: 1.75;
  color: var(--ink-60);
}

/* ---------- 05 术语表 ---------- */
.page-about .about-term-list {
  display: grid;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-term-list li {
  display: grid;
  gap: 6px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--ink-60);
}

.page-about .about-term-list li .mono {
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  color: var(--c-lake);
}

/* ---------- 06 核对入口 ---------- */
.page-about .about-reach {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-roles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-cadence {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-term-list li {
    grid-template-columns: 120px minmax(0, 1fr);
    gap: 20px;
    align-items: baseline;
  }
}

@media (min-width: 760px) {
  .page-about .about-steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
  }
}

@media (min-width: 760px) and (hover: hover) {
  .page-about .about-step .about-step-more {
    max-height: 0;
    opacity: 0;
  }

  .page-about .about-step:hover .about-step-more,
  .page-about .about-step:focus-visible .about-step-more,
  .page-about .about-step:focus-within .about-step-more {
    max-height: 200px;
    opacity: 1;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    gap: 0;
    align-items: stretch;
    border-radius: var(--r-lg);
    overflow: hidden;
    box-shadow: var(--shadow-card);
  }

  .page-about .about-hero-main {
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    min-height: 400px;
    padding: 52px 52px 48px;
    border-radius: 0;
  }

  .page-about .about-hero-aside {
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 52px 44px;
    border: 0;
    border-left: 1px solid var(--line);
    border-radius: 0;
    box-shadow: none;
  }

  .page-about .about-section {
    display: grid;
    grid-template-columns: var(--about-head-col) minmax(0, 1fr);
    gap: clamp(28px, 5vw, 64px);
    align-items: start;
  }

  .page-about .about-section-head {
    margin-bottom: 0;
  }

  .page-about .about-term-list li {
    grid-template-columns: 140px minmax(0, 1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-roles li,
  .page-about .about-step,
  .page-about .about-timeline-item,
  .page-about .about-toc-link,
  .page-about .about-inline-link,
  .page-about .about-step .about-step-more {
    transition: none;
  }

  .page-about .about-roles li:hover,
  .page-about .about-step:hover,
  .page-about .about-step:focus-visible,
  .page-about .about-timeline-item:hover {
    transform: none;
  }
}