.page-about {
  --about-veil: rgba(244, 239, 227, .045);
  --about-edge: rgba(201, 162, 77, .32);
  background: var(--navy-900);
  color: var(--cream);
  padding-bottom: 64px;
}

/* 面包屑 */
.page-about .about-top {
  padding-top: 26px;
}

.page-about .crumbs {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--grey-cool);
}

.page-about .crumbs a {
  color: var(--gold);
  text-decoration: none;
  transition: color .2s ease;
}

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

.page-about .crumb-sep {
  margin: 0 .6em;
  color: var(--line);
}

.page-about .crumbs [aria-current="page"] {
  color: var(--cream-2);
}

/* 首屏框景 */
.page-about .about-hero {
  padding: 34px 0 18px;
  background: linear-gradient(180deg, var(--navy-800) 0%, rgba(11, 19, 48, 0) 100%);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 34px;
  padding-bottom: 36px;
}

.page-about .about-hero__lead {
  border-left: 2px solid var(--gold);
  padding-left: 18px;
}

.page-about .about-hero__title {
  font-family: var(--font-serif);
  font-size: clamp(2.05rem, 7.4vw, 4.1rem);
  line-height: 1.08;
  letter-spacing: .01em;
  margin: .32em 0 .5em;
  color: var(--cream);
}

.page-about .about-hero__lede {
  max-width: 48ch;
  font-size: 1rem;
  line-height: 1.88;
  color: var(--cream-2);
}

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

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px 18px;
}

.page-about .about-stat {
  border-top: 1px solid var(--line);
  padding-top: 12px;
  min-width: 0;
}

.page-about .about-stat__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 1.7rem;
  line-height: 1.1;
  color: var(--gold-bright);
  letter-spacing: -.01em;
}

.page-about .about-stat__unit {
  font-size: .76rem;
  color: var(--gold);
  margin-left: .35em;
  letter-spacing: .04em;
}

.page-about .about-stat__label {
  margin: .55em 0 0;
  font-size: .8rem;
  line-height: 1.65;
  color: var(--grey-cool);
}

.page-about .about-hero__figure {
  margin: 0 0 4px;
  border: 1px solid var(--about-edge);
  background: var(--navy-800);
}

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

/* 章节节奏 */
.page-about .section {
  padding: 56px 0;
}

.page-about .section-head {
  gap: 16px;
  margin-bottom: 32px;
}

.page-about .eyebrow {
  margin: 0 0 .85em;
}

.page-about .about-meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .1em;
  color: var(--grey-cool);
}

.page-about .h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 4.2vw, 2.25rem);
  line-height: 1.24;
  letter-spacing: .01em;
  margin: 0;
  color: var(--cream);
}

.page-about .h3 {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  line-height: 1.42;
  margin: 0 0 .55em;
  color: var(--cream);
}

.page-about .prose {
  color: var(--cream-2);
  font-size: .96rem;
  line-height: 1.9;
}

.page-about .prose p {
  margin: 0 0 1.1em;
}

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

/* 站点概述 */
.page-about .about-scope__grid {
  gap: 32px;
  align-items: start;
}

.page-about .about-index-card {
  background: var(--about-veil);
  border: 1px solid var(--line-soft);
  border-top: 2px solid var(--gold);
  padding: 22px 20px 8px;
}

.page-about .about-index {
  list-style: none;
  margin: 4px 0 0;
  padding: 0;
}

.page-about .about-index li {
  display: flex;
  gap: 12px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: .88rem;
  line-height: 1.7;
  color: var(--cream-2);
}

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

.page-about .about-index__no {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .06em;
  color: var(--vermilion-bright);
  padding-top: .35em;
}

/* 使用体验 */
.page-about .about-route__grid {
  gap: 30px;
  align-items: center;
}

.page-about .about-route__body .h2 {
  margin: .3em 0 .7em;
}

.page-about .about-route__figure {
  margin: 0;
  border: 1px solid var(--line-soft);
}

/* 内容方向 */
.page-about .about-paths__grid {
  display: grid;
  gap: 18px;
}

.page-about .about-card {
  position: relative;
  padding: 26px 22px 24px;
  background: var(--about-veil);
  border: 1px solid var(--line-soft);
  transition: border-color .25s ease, transform .25s ease;
}

.page-about .about-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 46px;
  height: 2px;
  background: var(--gold);
}

.page-about .about-card:nth-child(even)::before {
  background: var(--vermilion);
}

.page-about .about-card:hover {
  border-color: var(--about-edge);
  transform: translateY(-2px);
}

.page-about .about-card .num-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--vermilion-bright);
  margin: 0 0 14px;
}

.page-about .about-card p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.86;
  color: var(--cream-2);
}

.page-about .about-paths__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

/* 使用过程 */
.page-about .about-flow__title {
  margin-bottom: 30px;
}

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

.page-about .about-step {
  position: relative;
  padding: 22px 0 24px 44px;
  border-left: 1px solid var(--line);
}

.page-about .about-step::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 28px;
  width: 7px;
  height: 7px;
  background: var(--gold);
  border-radius: 50%;
}

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

.page-about .about-step__no {
  display: block;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .18em;
  color: var(--gold);
  margin-bottom: 8px;
}

.page-about .about-step p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.82;
  color: var(--cream-2);
}

/* 使用场景 */
.page-about .about-uses__grid {
  display: grid;
  gap: 20px;
}

.page-about .about-use {
  padding-top: 18px;
  border-top: 2px solid var(--vermilion);
}

.page-about .about-use:nth-child(2) {
  border-top-color: var(--gold);
}

.page-about .about-use:nth-child(3) {
  border-top-color: var(--gold-bright);
}

.page-about .about-use p {
  margin: 0;
  font-size: .9rem;
  line-height: 1.86;
  color: var(--cream-2);
}

/* 维护日常 */
.page-about .about-upkeep__grid {
  display: grid;
  gap: 30px;
  align-items: center;
}

.page-about .about-upkeep__body .h2 {
  margin: .3em 0 .75em;
}

.page-about .about-upkeep__figure {
  margin: 0;
  border: 1px solid var(--line-soft);
}

/* 开始使用 */
.page-about .about-start__panel {
  position: relative;
  padding: 32px 22px 30px;
  background: linear-gradient(135deg, var(--navy-700) 0%, var(--navy-800) 70%);
  border: 1px solid var(--about-edge);
}

.page-about .about-start__panel::after {
  content: "";
  position: absolute;
  top: 16px;
  right: 16px;
  width: 32px;
  height: 32px;
  border-top: 1px solid var(--gold);
  border-right: 1px solid var(--gold);
  opacity: .8;
}

.page-about .about-start__lede {
  margin: .2em 0 2em;
  max-width: 56ch;
  color: var(--cream-2);
}

.page-about .about-start__grid {
  display: grid;
  gap: 28px;
}

.page-about .about-start__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-content: start;
}

.page-about .about-contact {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-contact li {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 14px;
  padding: 10px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: .9rem;
  line-height: 1.7;
  color: var(--cream-2);
  word-break: break-word;
}

.page-about .about-contact li:first-child {
  padding-top: 0;
}

.page-about .about-contact__k {
  flex: 0 0 auto;
  min-width: 46px;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--gold);
  padding-top: .28em;
}

.page-about .about-contact__note {
  margin: 16px 0 0;
  font-size: .8rem;
  line-height: 1.72;
  color: var(--grey-cool);
}

/* 桌面布局 */
@media (min-width: 760px) {
  .page-about .about-meta {
    white-space: nowrap;
  }

  .page-about .about-paths__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px;
  }

  .page-about .about-index-card {
    padding: 26px 24px 10px;
  }
}

@media (min-width: 900px) {
  .page-about .section {
    padding: 86px 0;
  }

  .page-about .section-head {
    margin-bottom: 40px;
  }

  .page-about .about-hero {
    padding: 46px 0 22px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: 1.35fr .85fr;
    gap: 60px;
    align-items: end;
    padding-bottom: 52px;
  }

  .page-about .about-hero__lead {
    padding-left: 28px;
  }

  .page-about .about-stats {
    gap: 28px 24px;
  }

  .page-about .about-scope__grid,
  .page-about .about-route__grid {
    gap: 58px;
  }

  .page-about .about-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 26px;
  }

  .page-about .about-step {
    padding: 26px 0 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .page-about .about-step::before {
    left: 0;
    top: -4px;
  }

  .page-about .about-uses__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 28px;
  }

  .page-about .about-upkeep__grid {
    grid-template-columns: 1.35fr .85fr;
    gap: 56px;
  }

  .page-about .about-start__panel {
    padding: 50px 52px 46px;
  }

  .page-about .about-start__grid {
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-card {
    transition: none;
  }

  .page-about .about-card:hover {
    transform: none;
  }
}