.page-about {
  --about-grid-line: rgba(36, 26, 18, 0.075);
  --about-hair: rgba(36, 26, 18, 0.22);
  background: var(--paper);
  color: var(--brown);
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  border-bottom: var(--edge);
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--about-grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-grid-line) 1px, transparent 1px);
  background-size: 100% 34px, 34px 100%;
  padding: 28px 0 42px;
}

.page-about .about-hero__eyebrow {
  margin: 22px 0 10px;
}

.page-about .about-hero__title {
  margin: 0 0 18px;
  font-size: clamp(2rem, 8vw, 3.6rem);
  line-height: 1.06;
  letter-spacing: -0.025em;
  font-weight: 900;
  max-width: 18ch;
}

.page-about .about-hero__lead {
  margin: 0 0 30px;
  font-size: clamp(1rem, 2.4vw, 1.14rem);
  line-height: 1.8;
  max-width: 64ch;
  color: #382a1e;
}

/* 统计条 */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border: var(--edge);
  box-shadow: var(--hard);
  background: var(--ink-900);
  color: var(--paper);
}

.page-about .about-stats__item {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas:
    "label label"
    "num unit"
    "note note";
  align-items: baseline;
  gap: 2px 8px;
  padding: 16px 16px 14px;
  border-right: 1px solid rgba(243, 236, 224, 0.16);
  border-bottom: 1px solid rgba(243, 236, 224, 0.16);
  outline: none;
  transition: background 0.25s ease;
}

.page-about .about-stats__item:nth-child(2n) {
  border-right: 0;
}

.page-about .about-stats__item:nth-last-child(-n + 2) {
  border-bottom: 0;
}

.page-about .about-stats__item:hover,
.page-about .about-stats__item:focus-visible {
  background: var(--ink-800);
}

.page-about .about-stats__item:focus-visible {
  box-shadow: inset 0 0 0 2px var(--mint);
}

.page-about .about-stats__label {
  grid-area: label;
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: rgba(243, 236, 224, 0.62);
  margin-bottom: 6px;
}

.page-about .about-stats__num {
  grid-area: num;
  font-size: clamp(1.9rem, 7vw, 2.6rem);
  line-height: 1;
  color: var(--orange);
}

.page-about .about-stats__unit {
  grid-area: unit;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: rgba(243, 236, 224, 0.72);
}

.page-about .about-stats__note {
  grid-area: note;
  display: block;
  margin-top: 6px;
  font-size: 0.7rem;
  line-height: 1.5;
  letter-spacing: 0.02em;
  color: var(--mint);
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, opacity 0.3s ease;
}

.page-about .about-stats__item:hover .about-stats__note,
.page-about .about-stats__item:focus-visible .about-stats__note {
  max-height: 3.4em;
  opacity: 1;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 34px;
  padding-top: 40px;
  padding-bottom: 56px;
}

.page-about .about-rail__title {
  margin: 0 0 12px;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--brick);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail__link {
  display: inline-block;
  white-space: nowrap;
  padding: 7px 13px;
  border: 2px solid var(--brown);
  background: var(--paper-2);
  color: var(--brown);
  font-size: 0.85rem;
  font-weight: 700;
  text-decoration: none;
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  background: var(--orange);
  color: var(--paper-2);
  transform: translateY(-2px);
}

/* ---------- 长文区块 ---------- */
.page-about .about-block {
  border-top: 3px solid var(--brown);
  padding-top: 20px;
  padding-bottom: 52px;
}

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

.page-about .about-block__tag {
  display: inline-block;
  margin: 0 0 14px;
  padding: 3px 10px;
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--brick);
  background: rgba(194, 65, 42, 0.1);
  border: 1px solid rgba(194, 65, 42, 0.4);
}

.page-about .about-block h2 {
  margin: 0 0 18px;
  font-size: clamp(1.55rem, 4.8vw, 2.15rem);
  line-height: 1.18;
  letter-spacing: -0.015em;
  font-weight: 900;
  max-width: 22ch;
}

.page-about .about-block p {
  margin: 0 0 16px;
  font-size: 1.02rem;
  line-height: 1.82;
  max-width: 66ch;
}

.page-about .about-k {
  font-style: normal;
  font-weight: 700;
  padding: 0 4px;
  background: rgba(255, 90, 31, 0.14);
  border-bottom: 2px solid var(--orange);
}

/* ---------- 图文错位 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

.page-about .about-figure {
  margin: 22px 0 0;
  border: var(--edge);
  box-shadow: var(--hard);
  background: var(--paper-2);
}

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

.page-about .about-figure figcaption {
  padding: 9px 12px;
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: var(--slate);
  border-top: 2px solid var(--brown);
  background: var(--paper-2);
}

/* ---------- 数据面板清单 ---------- */
.page-about .about-panels {
  list-style: none;
  margin: 4px 0 20px;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  max-width: 66ch;
}

.page-about .about-panels li {
  font-family: var(--mono);
  font-size: 0.76rem;
  letter-spacing: 0.04em;
  padding: 5px 11px;
  border: 2px solid var(--brown);
  background: var(--paper-2);
  transition: background 0.2s ease, color 0.2s ease;
}

.page-about .about-panels li:hover {
  background: var(--ink-900);
  color: var(--mint);
}

/* ---------- 流程 ---------- */
.page-about .about-figure--wide {
  margin-bottom: 26px;
}

.page-about .about-flow {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .about-flow__step {
  position: relative;
  border: 2px solid var(--brown);
  border-left-width: 8px;
  background: var(--paper-2);
  padding: 16px 18px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.page-about .about-flow__step:hover {
  transform: translateX(4px);
  box-shadow: 6px 6px 0 rgba(36, 26, 18, 0.18);
}

.page-about .about-flow__time {
  display: inline-block;
  margin-bottom: 8px;
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--ink-900);
  background: var(--mint);
  padding: 2px 8px;
}

.page-about .about-flow__step h3 {
  margin: 0 0 8px;
  font-size: 1.06rem;
  line-height: 1.4;
  font-weight: 800;
}

.page-about .about-flow__step p {
  margin: 0;
  font-size: 0.96rem;
  line-height: 1.75;
  color: #3b2d20;
}

.page-about .about-flow__note {
  margin: 0;
  padding: 14px 16px;
  border-left: 6px solid var(--brick);
  background: rgba(194, 65, 42, 0.07);
  font-size: 0.96rem;
}

/* ---------- 全宽引述 ---------- */
.page-about .about-quote {
  margin: 4px 0 52px;
  padding: 26px 22px 22px;
  border: var(--edge);
  border-left-width: 12px;
  border-left-color: var(--brick);
  background: var(--paper-2);
  box-shadow: var(--hard);
}

.page-about .about-quote blockquote {
  margin: 0 0 14px;
}

.page-about .about-quote blockquote p {
  margin: 0;
  font-size: clamp(1.14rem, 3.6vw, 1.5rem);
  line-height: 1.6;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ink-900);
}

.page-about .about-quote figcaption {
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--brick);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  list-style: none;
  margin: 0 0 34px;
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 8px;
  width: 3px;
  background: var(--brown);
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 26px;
}

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

.page-about .about-timeline__node {
  position: absolute;
  left: -26px;
  top: 5px;
  width: 15px;
  height: 15px;
  background: var(--paper-2);
  border: 3px solid var(--brown);
  transition: background 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease;
}

.page-about .about-timeline__item:hover .about-timeline__node,
.page-about .about-timeline__item:focus-within .about-timeline__node {
  background: var(--orange);
  transform: scale(1.12);
  box-shadow: 0 0 0 6px rgba(255, 90, 31, 0.18);
}

.page-about .about-timeline__when {
  display: block;
  margin-bottom: 7px;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--brick);
}

.page-about .about-timeline__item h3 {
  margin: 0 0 8px;
  font-size: 1.1rem;
  line-height: 1.4;
  font-weight: 800;
}

.page-about .about-timeline__item p {
  margin: 0;
  font-size: 0.97rem;
  line-height: 1.78;
  max-width: 62ch;
  color: #3b2d20;
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  border-top: 3px solid var(--brown);
  padding-top: 20px;
}

.page-about .about-next__label {
  margin: 0 0 14px;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--slate);
}

.page-about .about-next__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 显现动画 ---------- */
.page-about [data-reveal] {
  opacity: 1;
}

.js .page-about [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.js .page-about [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .js .page-about [data-reveal] {
    transition: none !important;
    animation: none !important;
    opacity: 1 !important;
    transform: none !important;
  }
}

/* ---------- 窄屏收紧 ---------- */
@media (max-width: 480px) {
  .page-about .about-stats {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .about-stats__item {
    border-right: 0;
  }

  .page-about .about-stats__item:nth-last-child(-n + 2) {
    border-bottom: 1px solid rgba(243, 236, 224, 0.16);
  }

  .page-about .about-stats__item:last-child {
    border-bottom: 0;
  }

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

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero {
    padding: 40px 0 54px;
  }

  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-stats__item {
    border-right: 1px solid rgba(243, 236, 224, 0.16);
    border-bottom: 0;
  }

  .page-about .about-stats__item:nth-child(2n) {
    border-right: 1px solid rgba(243, 236, 224, 0.16);
  }

  .page-about .about-stats__item:last-child {
    border-right: 0;
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: start;
    gap: 30px;
  }

  .page-about .about-split .about-figure {
    margin-top: 4px;
  }

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

  .page-about .about-figure--wide {
    max-width: 78%;
  }

  .page-about .about-figure--tall {
    max-width: 70%;
  }
}

/* ---------- 桌面：左窄右宽长文 + 粘性目录 ---------- */
@media (min-width: 1000px) {
  .page-about .about-shell {
    grid-template-columns: 232px minmax(0, 1fr);
    gap: 60px;
    padding-top: 56px;
    padding-bottom: 80px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
    border-top: 3px solid var(--brown);
    padding-top: 18px;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    overflow: visible;
    gap: 9px;
  }

  .page-about .about-rail__link {
    display: block;
    width: 100%;
    white-space: normal;
  }

  .page-about .about-hero__title {
    max-width: 16ch;
  }

  .page-about .about-quote {
    padding: 34px 34px 26px;
  }
}