.page-about {
  --about-rail-w: 178px;
  --about-ink-soft: rgba(18, 26, 23, 0.74);
  background:
    radial-gradient(120% 78% at 88% -12%, rgba(232, 132, 60, 0.16), transparent 62%),
    linear-gradient(180deg, var(--im-cream) 0%, var(--im-cream) 52%, var(--im-mist) 100%);
  color: var(--im-ink);
  padding-bottom: clamp(3rem, 8vw, 6rem);
  overflow-x: clip;
}

.page-about .im-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
  padding: 1.1rem 0 0;
  font-size: 0.85rem;
  color: var(--im-stone);
}

.page-about .im-breadcrumb a {
  color: var(--im-green);
  text-decoration: none;
  border-bottom: 1px dotted rgba(31, 61, 54, 0.45);
}

.page-about .im-breadcrumb a:hover {
  color: var(--im-orange);
  border-bottom-color: var(--im-orange);
}

.page-about .im-breadcrumb [aria-current="page"] {
  color: var(--im-stone);
}

.page-about .about-crumb-sep {
  color: var(--im-gold);
  font-size: 0.95rem;
}

/* 开篇 */
.page-about .about-masthead {
  position: relative;
  padding: clamp(1.6rem, 5vw, 2.8rem) 0 clamp(1.6rem, 4vw, 2.4rem);
  border-bottom: 1px dashed var(--im-line-gold);
}

.page-about .about-masthead .im-eyebrow {
  margin: 0;
  font-size: 0.78rem;
  letter-spacing: 0.26em;
  color: var(--im-clay);
}

.page-about .about-masthead h1 {
  margin: 0.6rem 0 0;
  max-width: 14em;
  font-family: var(--im-serif);
  font-weight: 700;
  font-size: clamp(1.95rem, 6.2vw, 3.6rem);
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--im-green);
}

.page-about .about-lead {
  margin: clamp(1rem, 3vw, 1.5rem) 0 0;
  max-width: 42em;
  font-size: clamp(1rem, 2.6vw, 1.15rem);
  line-height: 1.85;
  color: var(--about-ink-soft);
}

.page-about .about-annotation {
  display: none;
}

@media (min-width: 1100px) {
  .page-about .about-annotation {
    display: block;
    position: absolute;
    right: -0.4rem;
    top: clamp(2.4rem, 6vw, 4.2rem);
    writing-mode: vertical-rl;
    font-family: var(--im-serif);
    font-size: 0.88rem;
    letter-spacing: 0.34em;
    color: var(--im-clay);
    opacity: 0.85;
  }
}

/* 轨道 + 正文 */
.page-about .about-shell {
  padding-top: clamp(1.8rem, 5vw, 3rem);
}

.page-about .about-rail {
  display: none;
}

.page-about .about-flow {
  min-width: 0;
}

@media (min-width: 1024px) {
  .page-about .about-shell {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    column-gap: clamp(2rem, 5vw, 4.5rem);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 8.5rem;
  }
}

.page-about .about-rail-title {
  margin: 0 0 1rem;
  font-family: var(--im-serif);
  font-size: 0.8rem;
  letter-spacing: 0.28em;
  color: var(--im-stone);
}

.page-about .about-rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 1px solid var(--im-line);
}

.page-about .about-rail-link {
  position: relative;
  display: block;
  padding: 0.58rem 0 0.58rem 1.05rem;
  font-size: 0.92rem;
  line-height: 1.5;
  color: var(--im-stone);
  text-decoration: none;
  transition: color 0.22s ease;
}

.page-about .about-rail-link::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 0.95rem;
  width: 3px;
  height: 0;
  border-radius: 2px;
  background: var(--im-orange);
  transition: height 0.25s ease;
}

.page-about .about-rail-link:hover {
  color: var(--im-clay);
}

.page-about .about-rail-link[aria-current="true"] {
  color: var(--im-green);
  font-weight: 700;
}

.page-about .about-rail-link[aria-current="true"]::before {
  height: 1.15rem;
}

/* 章节骨架 */
.page-about .about-section {
  padding: clamp(2.2rem, 6vw, 3.6rem) 0;
  scroll-margin-top: 7.5rem;
}

.page-about .about-section + .about-section {
  border-top: 1px dashed var(--im-line-gold);
}

.page-about .about-chapter-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.35rem 1rem;
  align-items: start;
  margin-bottom: clamp(1.2rem, 3.5vw, 2rem);
}

.page-about .about-chapter-num {
  font-family: var(--im-num);
  font-weight: 700;
  font-size: clamp(2.6rem, 8vw, 4.2rem);
  line-height: 0.8;
  letter-spacing: 0.02em;
  color: rgba(232, 132, 60, 0.24);
  -webkit-text-stroke: 1.2px rgba(232, 132, 60, 0.9);
}

.page-about .about-chapter-title {
  margin: 0;
  font-family: var(--im-serif);
  font-weight: 700;
  font-size: clamp(1.5rem, 4.6vw, 2.2rem);
  line-height: 1.32;
  color: var(--im-green);
}

.page-about .about-chapter-sub {
  margin: 0.5rem 0 0;
  font-size: 0.88rem;
  letter-spacing: 0.04em;
  line-height: 1.6;
  color: var(--im-stone);
}

/* 正文与图片 */
.page-about .about-text {
  max-width: 40em;
  margin: 0;
  font-size: 1rem;
  line-height: 1.9;
  color: var(--about-ink-soft);
}

.page-about .about-text + .about-text {
  margin-top: 1rem;
}

.page-about .about-figure {
  position: relative;
  margin: 0;
  padding: 0.55rem;
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.88);
  border-radius: var(--im-radius-lg);
  box-shadow: var(--im-shadow);
  transform: rotate(-1.4deg);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: calc(var(--im-radius-lg) - 8px);
  object-fit: cover;
}

.page-about .about-figure figcaption {
  margin: 0.7rem 0.3rem 0.2rem;
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--im-stone);
}

.page-about .about-figure--wide {
  margin-top: clamp(1.6rem, 4.5vw, 2.4rem);
  transform: rotate(0.8deg);
}

/* 章节一 */
.page-about .about-origin {
  display: grid;
  gap: clamp(1.3rem, 4vw, 2rem);
}

.page-about .about-origin-text {
  min-width: 0;
}

@media (min-width: 780px) {
  .page-about .about-origin {
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
    align-items: start;
    gap: clamp(1.6rem, 4.5vw, 2.8rem);
  }
}

/* 章节二：三个习惯 */
.page-about .about-principles {
  list-style: none;
  margin: clamp(1.4rem, 4vw, 2.2rem) 0 0;
  padding: 0;
  display: grid;
  gap: 1rem;
}

.page-about .about-principle {
  padding: clamp(1rem, 3vw, 1.5rem) clamp(1rem, 3vw, 1.6rem);
  background: #fffaf0;
  border-left: 3px solid var(--im-orange);
  border-radius: 0 var(--im-radius) var(--im-radius) 0;
  box-shadow: var(--im-shadow-soft);
}

.page-about .about-principle-tag {
  display: inline-block;
  margin-bottom: 0.6rem;
  font-size: 0.74rem;
  letter-spacing: 0.16em;
}

.page-about .about-principle h3 {
  margin: 0 0 0.5rem;
  font-family: var(--im-serif);
  font-size: 1.12rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--im-green);
}

.page-about .about-principle p {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--about-ink-soft);
}

@media (min-width: 760px) {
  .page-about .about-principles {
    gap: 1.2rem;
  }

  .page-about .about-principle:nth-child(2) {
    margin-left: clamp(1rem, 4vw, 3rem);
    border-left-color: var(--im-gold);
  }

  .page-about .about-principle:nth-child(3) {
    margin-left: clamp(2rem, 8vw, 6rem);
    border-left-color: var(--im-moss);
  }
}

/* 章节三：时间线 */
.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 0.34rem;
  top: 0.7rem;
  bottom: 0.7rem;
  width: 1px;
  background: repeating-linear-gradient(
    to bottom,
    var(--im-line-gold) 0 6px,
    transparent 6px 13px
  );
}

.page-about .about-milestone {
  position: relative;
  padding-left: 2.1rem;
}

.page-about .about-milestone + .about-milestone {
  margin-top: 0.55rem;
}

.page-about .about-milestone::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.95rem;
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 2px;
  background: var(--im-gold);
  box-shadow: 0 0 0 3px rgba(217, 178, 106, 0.22);
}

.page-about .about-details {
  border-radius: 14px;
  transition: background 0.22s ease;
}

.page-about .about-details[open] {
  background: rgba(232, 132, 60, 0.07);
}

.page-about .about-summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.3rem 1rem;
  padding: 0.6rem 0.9rem;
  cursor: pointer;
  list-style: none;
  border-radius: 14px;
}

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

.page-about .about-summary:hover {
  background: rgba(232, 132, 60, 0.09);
}

.page-about .about-summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--im-num);
  font-size: 1.1rem;
  line-height: 1;
  color: var(--im-clay);
}

.page-about .about-details[open] .about-summary::after {
  content: "–";
  color: var(--im-orange);
}

.page-about .about-year {
  font-family: var(--im-num);
  font-weight: 700;
  font-size: clamp(1.5rem, 4.2vw, 2rem);
  line-height: 1.1;
  letter-spacing: 0.02em;
  color: var(--im-green);
}

.page-about .about-milestone-name {
  font-family: var(--im-serif);
  font-size: 1rem;
  line-height: 1.5;
  color: var(--im-clay);
}

.page-about .about-milestone-text {
  margin: 0.2rem 0 0.9rem;
  padding: 0 0.9rem;
  max-width: 38em;
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--about-ink-soft);
}

/* 章节四：团队 */
.page-about .about-team {
  display: grid;
  gap: clamp(1.4rem, 4vw, 2.2rem);
}

.page-about .about-team-text {
  min-width: 0;
}

.page-about .about-figure--side {
  transform: rotate(1.1deg);
  align-self: start;
}

@media (min-width: 900px) {
  .page-about .about-team {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: start;
  }
}

.page-about .about-stats {
  list-style: none;
  margin: clamp(1.4rem, 4vw, 1.9rem) 0 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

@media (min-width: 620px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0.8rem;
  }
}

.page-about .about-stat {
  padding: 0.9rem 1rem 1rem;
  border-radius: var(--im-radius);
  background: rgba(255, 255, 255, 0.62);
  border: 1px solid rgba(255, 255, 255, 0.88);
  box-shadow: var(--im-shadow-soft);
}

.page-about .about-stat-num {
  display: block;
  font-family: var(--im-num);
  font-weight: 700;
  font-size: clamp(1.8rem, 5vw, 2.3rem);
  line-height: 1;
  color: var(--im-orange);
}

.page-about .about-stat-label {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.85rem;
  line-height: 1.65;
  color: var(--im-stone);
}

/* 章节五：价值主张 */
.page-about .about-glass {
  padding: clamp(1.2rem, 3.6vw, 2rem);
  background: rgba(255, 255, 255, 0.56);
  border: 1px solid rgba(255, 255, 255, 0.85);
  border-radius: var(--im-radius-lg);
  box-shadow: var(--im-shadow-soft);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.page-about .about-quote {
  margin: 0;
  padding: 0.15rem 0 0.15rem clamp(1rem, 3vw, 1.5rem);
  border-left: 4px solid var(--im-orange);
  font-family: var(--im-serif);
  font-size: clamp(1.08rem, 3.4vw, 1.45rem);
  line-height: 1.75;
  color: var(--im-green);
}

.page-about .about-values {
  list-style: none;
  margin: clamp(1.3rem, 4vw, 1.8rem) 0 0;
  padding: 0;
  display: grid;
  gap: 1rem;
}

@media (min-width: 860px) {
  .page-about .about-values {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.1rem;
  }
}

.page-about .about-value {
  padding: clamp(0.95rem, 3vw, 1.3rem) clamp(1rem, 3vw, 1.35rem);
  background: rgba(251, 244, 232, 0.86);
  border: 1px solid var(--im-line);
  border-radius: var(--im-radius);
}

.page-about .about-value h3 {
  margin: 0 0 0.5rem;
  font-family: var(--im-serif);
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--im-green);
}

.page-about .about-value p {
  margin: 0;
  font-size: 0.93rem;
  line-height: 1.85;
  color: var(--about-ink-soft);
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: clamp(1.6rem, 4vw, 2.2rem);
}

.page-about .im-btn {
  text-decoration: none;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-figure,
  .page-about .about-figure--side,
  .page-about .about-figure--wide {
    transform: none;
  }
}