.page-about{
  --about-pad-x: clamp(1.25rem, 5vw, 3rem);
  --about-sec-y: clamp(3rem, 8vw, 5.5rem);
  background: var(--ink-900);
  color: var(--mist);
  font-family: var(--font-sans);
  overflow-x: hidden;
}

.page-about .about-crumb{
  padding-top: 1.5rem;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero{
  position: relative;
  padding-top: 1rem;
  background:
    radial-gradient(120% 90% at 88% -20%, rgba(183, 255, 42, .10), transparent 62%),
    linear-gradient(180deg, var(--ink-900), var(--ink-900));
}

.page-about .about-hero__title{
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(2rem, 7.6vw, 4.3rem);
  line-height: 1.1;
  letter-spacing: .01em;
  margin: .8rem 0 1.6rem;
  color: var(--mist);
}

.page-about .about-hero__grid{
  display: grid;
  gap: 1.75rem;
  align-items: start;
}

.page-about .about-hero__lead{
  margin: 0;
  font-size: clamp(1rem, 2.3vw, 1.125rem);
  line-height: 1.9;
  color: var(--mist-80);
  max-width: 48ch;
}

.page-about .about-hero__note{
  border-left: 1px solid var(--hair-strong);
  padding-left: 1.1rem;
}

.page-about .about-hero__note-label{
  margin: 0 0 .75rem;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--amber);
}

.page-about .about-hero__note-list{
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: .6rem;
}

.page-about .about-hero__note-list li{
  position: relative;
  padding-left: .95rem;
  font-size: .8125rem;
  line-height: 1.75;
  color: var(--mist-66);
}

.page-about .about-hero__note-list li::before{
  content: "";
  position: absolute;
  left: 0;
  top: .68em;
  width: .55rem;
  height: 1px;
  background: var(--lime);
}

.page-about .about-hero__figure{
  margin: 2.5rem 0 0;
  position: relative;
}

.page-about .about-hero__figure img{
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% 93%, 0 100%);
}

.page-about .about-hero__caption{
  margin-top: .8rem;
  padding: 0 var(--about-pad-x);
  font-size: .75rem;
  letter-spacing: .04em;
  color: var(--mute);
}

/* ---------- 通用章节 ---------- */
.page-about .about-sec{
  padding: var(--about-sec-y) 0;
}

.page-about .about-sec__grid{
  display: grid;
  gap: 1.5rem;
}

.page-about .about-sec__kicker{
  margin: 0;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .about-sec__note{
  margin: .8rem 0 0;
  font-size: .8125rem;
  line-height: 1.8;
  color: var(--mute);
  max-width: 30ch;
}

.page-about .about-sec__title{
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(1.5rem, 4.2vw, 2.3rem);
  line-height: 1.28;
  margin: 0 0 1.25rem;
  color: var(--mist);
}

.page-about .about-sec__body p{
  margin: 0 0 1rem;
  font-size: 1rem;
  line-height: 1.9;
  color: var(--mist-80);
  max-width: 62ch;
}

.page-about .about-sec__tail{
  margin-top: 1.5rem !important;
  padding-top: 1.25rem;
  border-top: 1px solid var(--hair-soft);
  font-size: .9375rem !important;
  color: var(--mist-66) !important;
}

.page-about .about-link{
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(183, 255, 42, .36);
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

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

/* ---------- 方法 ---------- */
.page-about .about-sec--method{
  background: linear-gradient(180deg, rgba(27, 38, 48, .62), rgba(27, 38, 48, 0) 72%);
  border-top: 1px solid var(--hair-soft);
  border-bottom: 1px solid var(--hair-soft);
}

.page-about .about-steps{
  list-style: none;
  margin: 1.5rem 0 0;
  padding: 0;
  display: grid;
  gap: .85rem;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
}

.page-about .about-steps li{
  border-left: 1px solid var(--hair-strong);
  padding-left: .8rem;
  font-size: .875rem;
  line-height: 1.5;
  color: var(--mist-66);
  letter-spacing: .04em;
}

.page-about .about-steps__num{
  display: block;
  margin-bottom: .3rem;
  font-size: .75rem;
  color: var(--lime-deep);
  letter-spacing: .12em;
}

.page-about .method-layout{
  display: grid;
  gap: 2rem;
  margin-top: 2.5rem;
}

.page-about .method-figure{
  margin: 0;
}

.page-about .method-figure img{
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--hair);
  background: var(--ink-700);
}

.page-about .method-figure__caption{
  margin-top: .7rem;
  font-size: .75rem;
  line-height: 1.7;
  color: var(--mute);
  max-width: 40ch;
}

.page-about .method-list{
  display: flex;
  flex-direction: column;
}

.page-about .method-item{
  border-top: 1px solid var(--hair);
}

.page-about .method-item:last-of-type{
  border-bottom: 1px solid var(--hair);
}

.page-about .method-item__sum{
  display: flex;
  align-items: baseline;
  gap: .9rem;
  padding: 1.05rem .25rem;
  cursor: pointer;
  list-style: none;
  color: var(--mist);
  transition: background-color .2s var(--ease);
}

.page-about .method-item__sum::-webkit-details-marker{
  display: none;
}

.page-about .method-item__sum:hover{
  background: rgba(183, 255, 42, .05);
}

.page-about .method-item__idx{
  font-size: .75rem;
  color: var(--lime-deep);
  letter-spacing: .12em;
}

.page-about .method-item__name{
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: .02em;
}

.page-about .method-item__sum::after{
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: .9rem;
  color: var(--lime);
}

.page-about .method-item[open] .method-item__sum::after{
  content: "－";
}

.page-about .method-item[open] .method-item__sum{
  border-bottom: 1px solid var(--hair-soft);
}

.page-about .method-item__body{
  padding: .9rem .25rem 1.3rem 1.8rem;
}

.page-about .method-item__body p{
  margin: 0;
  font-size: .9rem;
  line-height: 1.85;
  color: var(--mist-66);
}

.page-about .method-list__foot{
  margin: 1.5rem 0 0;
  font-size: .875rem;
  line-height: 1.85;
  color: var(--mist-50);
}

/* ---------- 团队 ---------- */
.page-about .crew{
  display: grid;
  gap: 1.5rem;
  margin-top: 2rem;
  padding-bottom: 0;
}

.page-about .crew__item{
  border-top: 2px solid var(--hair-strong);
  padding-top: 1rem;
}

.page-about .crew__item:first-child{
  border-top-color: var(--lime);
}

.page-about .crew__num{
  font-size: clamp(2rem, 6vw, 3rem);
  line-height: 1;
  color: var(--lime);
  letter-spacing: .02em;
}

.page-about .crew__unit{
  margin-left: .3rem;
  font-size: .8rem;
  color: var(--mute);
}

.page-about .crew__name{
  margin: .6rem 0 .5rem;
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--mist);
}

.page-about .crew__desc{
  margin: 0;
  font-size: .875rem;
  line-height: 1.8;
  color: var(--mist-66);
}

/* ---------- 时间轴 ---------- */
.page-about .about-sec--timeline{
  background: linear-gradient(176deg, var(--ink-800) 0 74%, var(--ink-900) 74%);
  border-top: 1px solid var(--hair-soft);
}

.page-about .timeline-layout{
  display: grid;
  gap: 2.25rem;
  margin-top: 2.5rem;
}

.page-about .timeline{
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .timeline::before{
  content: "";
  position: absolute;
  left: 6px;
  top: .6rem;
  bottom: .6rem;
  width: 1px;
  background: linear-gradient(180deg, var(--lime) 0%, var(--lime-deep) 45%, var(--hair) 100%);
}

.page-about .timeline__item{
  position: relative;
  padding-left: 1.85rem;
  margin-bottom: 1.1rem;
}

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

.page-about .timeline__item::before{
  content: "";
  position: absolute;
  left: 1px;
  top: .62rem;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 1px solid var(--lime);
  box-shadow: 0 0 0 4px rgba(183, 255, 42, .10);
}

.page-about .stage__sum{
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5rem .7rem;
  padding: .45rem 0;
  cursor: pointer;
  list-style: none;
}

.page-about .stage__sum::-webkit-details-marker{
  display: none;
}

.page-about .stage__title{
  font-family: var(--font-serif);
  font-size: 1.05rem;
  line-height: 1.5;
  color: var(--mist);
  border-bottom: 1px solid transparent;
  transition: border-color .2s var(--ease);
}

.page-about .stage__sum:hover .stage__title{
  border-bottom-color: var(--hair-strong);
}

.page-about .stage__body{
  padding: 0 0 1rem;
}

.page-about .stage__body p{
  margin: .2rem 0 0;
  font-size: .875rem;
  line-height: 1.85;
  color: var(--mist-66);
  max-width: 54ch;
}

.page-about .timeline-figure{
  margin: 0;
}

.page-about .timeline-figure img{
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--hair);
  background: var(--ink-700);
}

.page-about .timeline-figure__caption{
  margin-top: .7rem;
  font-size: .75rem;
  line-height: 1.7;
  color: var(--mute);
}

/* ---------- 服务原则与联系 ---------- */
.page-about .principles{
  display: grid;
  gap: 1.5rem;
  margin-top: 2rem;
}

.page-about .principle{
  border-left: 1px solid var(--hair-strong);
  padding-left: 1rem;
}

.page-about .principle__name{
  margin: 0 0 .45rem;
  font-family: var(--font-serif);
  font-size: 1.1rem;
  line-height: 1.45;
  color: var(--mist);
}

.page-about .principle__desc{
  margin: 0;
  font-size: .875rem;
  line-height: 1.85;
  color: var(--mist-66);
}

.page-about .about-contact{
  margin-top: 2.5rem;
  display: grid;
  gap: 1.5rem;
  padding: clamp(1.25rem, 3.5vw, 2rem);
  background: var(--ink-800);
  border: 1px solid var(--hair);
  border-left: 2px solid var(--amber);
}

.page-about .about-contact__row{
  display: grid;
  gap: .25rem;
  margin: 0 0 1rem;
}

.page-about .about-contact__label{
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--mute);
}

.page-about .about-contact__value{
  font-family: var(--font-mono);
  font-size: .9375rem;
  line-height: 1.6;
  color: var(--mist);
  word-break: break-all;
}

.page-about .about-contact__value--text{
  font-family: var(--font-sans);
  font-size: .875rem;
  color: var(--mist-80);
}

.page-about .about-contact__actions{
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
  margin-top: 1.25rem;
}

.page-about .about-contact__status{
  min-height: 1.2em;
  margin: .6rem 0 0;
  font-size: .8rem;
  color: var(--lime);
}

.page-about .about-contact__note{
  margin: 0;
  padding-top: 1.25rem;
  border-top: 1px solid var(--hair-soft);
  font-size: .8125rem;
  line-height: 1.85;
  color: var(--mute);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px){
  .page-about .about-hero__grid{
    grid-template-columns: minmax(0, 1.55fr) minmax(0, .85fr);
    gap: 2.5rem;
    align-items: start;
  }

  .page-about .crew{
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.25rem;
  }

  .page-about .principles{
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.75rem 2rem;
  }
}

@media (min-width: 900px){
  .page-about .about-sec__grid{
    grid-template-columns: minmax(150px, 215px) minmax(0, 1fr);
    gap: 3rem;
  }

  .page-about .about-sec__aside{
    position: sticky;
    top: calc(var(--header-h) + 2rem);
    align-self: start;
  }

  .page-about .method-layout{
    grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr);
    gap: 3rem;
    align-items: start;
    padding-left: calc(215px + 3rem);
    margin-left: 0;
  }

  .page-about .timeline-layout{
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .65fr);
    gap: 3rem;
    align-items: start;
    padding-left: calc(215px + 3rem);
  }

  .page-about .timeline-figure{
    position: sticky;
    top: calc(var(--header-h) + 2rem);
  }

  .page-about .about-contact{
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    gap: 2rem;
  }

  .page-about .about-contact__note{
    border-top: 0;
    padding-top: 0;
    border-left: 1px solid var(--hair-soft);
    padding-left: 1.5rem;
  }

  .page-about .crew__item:nth-child(2){
    transform: translateY(1.5rem);
  }

  .page-about .crew{
    padding-bottom: 1.5rem;
  }
}

@media (min-width: 1200px){
  .page-about .about-hero__title{
    margin-bottom: 2rem;
  }

  .page-about .about-hero__caption{
    position: absolute;
    right: var(--about-pad-x);
    bottom: 1.5rem;
    max-width: 28ch;
    text-align: right;
    padding: 0;
    color: var(--mist-50);
  }
}

@media (prefers-reduced-motion: reduce){
  .page-about .about-link,
  .page-about .method-item__sum,
  .page-about .stage__title{
    transition: none;
  }
}
<<<END>>>