.page-about {
  --about-gold: #D4AF37;
  --about-gold-bright: #F0D060;
  --about-red: #8B0000;
  --about-navy: #0A1F44;
  --about-navy-deep: #071326;
  --about-bg: #F4F6F9;
  --about-bg-alt: #E8ECF1;
  --about-ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  background: var(--color-bg);
  color: var(--color-text);
}

/* ===== Hero ===== */
.page-about .about-hero {
  position: relative;
  padding: 36px 0 56px;
  background:
    radial-gradient(circle at 85% 15%, rgba(212, 175, 55, 0.18), transparent 40%),
    radial-gradient(circle at 8% 100%, rgba(30, 64, 118, 0.55), transparent 55%),
    linear-gradient(135deg, var(--about-navy) 0%, var(--about-navy-deep) 100%);
  color: var(--color-text-invert);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--about-gold) 0%, var(--about-gold-bright) 60%, var(--about-red) 100%);
  opacity: 0.85;
}

.page-about .about-hero__skew {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 28px;
  background: linear-gradient(102deg, transparent 0%, transparent 30%, rgba(212, 175, 55, 0.6) 50%, transparent 58%, transparent 100%);
  opacity: 0.5;
  pointer-events: none;
}

.page-about .about-hero .breadcrumb {
  margin-bottom: 24px;
}

.page-about .about-hero__body {
  display: grid;
  gap: 32px;
  align-items: start;
}

.page-about .about-hero__eyebrow {
  color: var(--about-gold-bright);
  letter-spacing: 0.1em;
}

.page-about .about-hero__main h1 {
  font-family: var(--font-head);
  font-size: clamp(36px, 8vw, 62px);
  font-weight: 700;
  line-height: 1.14;
  letter-spacing: 0.02em;
  margin: 14px 0 18px;
}

.page-about .about-hero__lead {
  max-width: 680px;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.84);
  margin: 0 0 22px;
}

.page-about .about-hero__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
}

.page-about .about-hero__tag {
  display: inline-block;
  padding: 5px 11px;
  border: 1px solid rgba(212, 175, 55, 0.55);
  border-radius: 2px;
  color: var(--about-gold-bright);
  font-size: 11px;
  letter-spacing: 0.06em;
  line-height: 1.4;
  white-space: nowrap;
}

.page-about .about-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  color: rgba(255, 255, 255, 0.62);
  font-size: 12px;
  letter-spacing: 0.04em;
}

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

/* ===== 里程碑图 ===== */
.page-about .about-milestone {
  padding: 36px 0 12px;
}

.page-about .about-milestone__figure {
  margin: 0;
  position: relative;
}

.page-about .about-milestone__figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 4px 4px 0 0;
  object-fit: cover;
}

.page-about .about-milestone__caption {
  margin-top: 10px;
  color: var(--color-link);
  font-size: 12px;
  letter-spacing: 0.08em;
}

/* ===== 品牌理念 ===== */
.page-about .about-philosophy {
  padding: 56px 0 48px;
  background:
    linear-gradient(120deg, rgba(232, 236, 241, 0.55), transparent 60%),
    var(--about-bg);
}

.page-about .about-philosophy__header {
  max-width: 720px;
  margin-bottom: 36px;
}

.page-about .about-philosophy__header h2 {
  font-family: var(--font-head);
  font-size: clamp(28px, 5vw, 40px);
  font-weight: 700;
  line-height: 1.2;
  margin: 10px 0 14px;
  color: var(--about-navy);
}

.page-about .about-philosophy__header p {
  font-size: 15px;
  line-height: 1.75;
  color: #555;
  margin: 0;
}

.page-about .about-philosophy__grid {
  display: grid;
  gap: 28px;
  align-items: start;
}

.page-about .about-philosophy__items {
  display: grid;
  gap: 12px;
}

.page-about .about-philosophy__item {
  position: relative;
  padding: 20px 18px 20px 24px;
  background: var(--about-bg-alt);
  border-left: 3px solid var(--about-gold);
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 0 100%);
}

.page-about .about-philosophy__num {
  display: block;
  color: var(--about-gold);
  font-size: 13px;
  letter-spacing: 0.08em;
  margin-bottom: 6px;
}

.page-about .about-philosophy__item h3 {
  font-family: var(--font-head);
  font-size: 19px;
  font-weight: 700;
  margin: 0 0 6px;
  color: var(--about-navy);
}

.page-about .about-philosophy__item p {
  font-size: 14px;
  line-height: 1.7;
  color: #444;
  margin: 0;
}

.page-about .about-philosophy__media {
  margin: 0;
}

.page-about .about-philosophy__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: 2px;
}

.page-about .about-philosophy__media figcaption {
  margin-top: 8px;
  color: var(--color-link);
  font-size: 12px;
  letter-spacing: 0.08em;
}

/* ===== 版本演进时间轴 ===== */
.page-about .about-timeline {
  padding: 56px 0;
  background: var(--about-bg-alt);
}

.page-about .about-timeline__header {
  max-width: 720px;
  margin-bottom: 36px;
}

.page-about .about-timeline__header h2 {
  font-family: var(--font-head);
  font-size: clamp(28px, 5vw, 40px);
  font-weight: 700;
  line-height: 1.2;
  margin: 10px 0 14px;
  color: var(--about-navy);
}

.page-about .about-timeline__header p {
  font-size: 15px;
  line-height: 1.75;
  color: #555;
  margin: 0;
}

.page-about .about-timeline__track {
  position: relative;
  display: grid;
  gap: 16px;
}

.page-about .about-timeline__track::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--about-gold), var(--about-red));
}

.page-about .about-timeline__entry {
  position: relative;
  padding-left: 48px;
}

.page-about .about-timeline__dot {
  position: absolute;
  left: 7px;
  top: 16px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--about-navy);
  border: 3px solid var(--about-gold);
  box-shadow: 0 0 0 4px rgba(212, 175, 55, 0.18);
}

.page-about .about-timeline__summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  padding: 8px 0;
}

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

.page-about .about-timeline__version {
  min-width: 44px;
  font-size: 14px;
  font-weight: 700;
  color: var(--about-gold);
  letter-spacing: 0.06em;
}

.page-about .about-timeline__title {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-text);
}

.page-about .about-timeline__content {
  padding: 14px 16px;
  background: var(--color-text-invert);
  border-left: 2px solid var(--about-gold);
  font-size: 14px;
  line-height: 1.7;
  color: #444;
}

.page-about .about-timeline__content p {
  margin: 0;
}

/* ===== 服务范围 ===== */
.page-about .about-services {
  padding: 56px 0;
  background: var(--about-bg);
}

.page-about .about-services__header {
  max-width: 720px;
  margin-bottom: 36px;
}

.page-about .about-services__header h2 {
  font-family: var(--font-head);
  font-size: clamp(28px, 5vw, 40px);
  font-weight: 700;
  line-height: 1.2;
  margin: 10px 0 14px;
  color: var(--about-navy);
}

.page-about .about-services__header p {
  font-size: 15px;
  line-height: 1.75;
  color: #555;
  margin: 0;
}

.page-about .about-services__grid {
  display: grid;
  gap: 20px;
}

.page-about .about-services__card {
  padding: 26px 24px;
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .about-services__card .mono-label {
  color: var(--about-gold);
  font-size: 12px;
  letter-spacing: 0.08em;
}

.page-about .about-services__card h3 {
  font-family: var(--font-head);
  font-size: 22px;
  font-weight: 700;
  margin: 0;
  line-height: 1.3;
}

.page-about .about-services__card p {
  font-size: 14px;
  line-height: 1.7;
  margin: 0;
  flex-grow: 1;
}

.page-about .about-services__card .btn {
  align-self: flex-start;
  margin-top: 6px;
}

.page-about .about-services__card--visitor {
  background: linear-gradient(135deg, var(--about-navy), var(--about-navy-deep));
  color: var(--color-text-invert);
}

.page-about .about-services__card--visitor p {
  color: rgba(255, 255, 255, 0.82);
}

.page-about .about-services__card--mobile {
  background: var(--about-bg-alt);
}

.page-about .about-services__card--returning {
  background: var(--color-text-invert);
  border: 1px solid var(--about-bg-alt);
}

/* ===== 技术与运维 ===== */
.page-about .about-tech {
  position: relative;
  padding: 60px 0;
  background: var(--about-navy-deep);
  color: var(--color-text-invert);
  overflow: hidden;
}

.page-about .about-tech__image {
  position: absolute;
  inset: 0;
  opacity: 0.28;
  z-index: 0;
}

.page-about .about-tech__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .about-tech > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-tech__header {
  max-width: 720px;
  margin-bottom: 36px;
}

.page-about .about-tech__header h2 {
  font-family: var(--font-head);
  font-size: clamp(28px, 5vw, 40px);
  font-weight: 700;
  line-height: 1.2;
  margin: 10px 0 14px;
}

.page-about .about-tech__header p {
  font-size: 15px;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.72);
  margin: 0;
}

.page-about .about-tech__list {
  display: grid;
  gap: 0;
}

.page-about .about-tech__item {
  display: grid;
  grid-template-columns: 52px 1fr;
  gap: 4px 16px;
  padding: 18px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.page-about .about-tech__item .mono-label {
  color: var(--about-gold);
  font-size: 13px;
  padding-top: 3px;
}

.page-about .about-tech__item h3 {
  font-family: var(--font-head);
  font-size: 18px;
  font-weight: 700;
  margin: 0;
}

.page-about .about-tech__item p {
  grid-column: 2;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.7);
  margin: 4px 0 0;
}

.page-about .about-tech__links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 28px;
}

/* ===== 桌面端布局增强 ===== */
@media (min-width: 768px) {
  .page-about .about-hero__body {
    grid-template-columns: minmax(0, 1fr) 160px;
    align-items: center;
  }

  .page-about .about-hero__side {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 8px;
    border-left: 1px solid rgba(255, 255, 255, 0.16);
    padding-left: 20px;
  }

  .page-about .about-hero__big {
    font-family: var(--font-head);
    font-size: 72px;
    font-weight: 700;
    line-height: 1;
    color: var(--about-gold);
    letter-spacing: 0.04em;
  }

  .page-about .about-hero__side-caption {
    color: rgba(255, 255, 255, 0.6);
    font-size: 11px;
    text-align: right;
    letter-spacing: 0.06em;
  }

  .page-about .about-philosophy__grid {
    grid-template-columns: minmax(0, 1fr) 300px;
    gap: 40px;
  }

  .page-about .about-timeline__track {
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
  }

  .page-about .about-timeline__track::before {
    content: none;
  }

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

  .page-about .about-services__card--visitor {
    grid-row: span 2;
  }

  .page-about .about-tech__list {
    grid-template-columns: repeat(2, 1fr);
    gap: 0 32px;
  }
}

@media (min-width: 992px) {
  .page-about .about-hero {
    padding: 48px 0 72px;
  }

  .page-about .about-hero__lead {
    font-size: 16px;
  }

  .page-about .about-hero__tags {
    margin-bottom: 26px;
  }

  .page-about .about-philosophy__grid {
    grid-template-columns: minmax(0, 1fr) 420px;
    gap: 60px;
  }

  .page-about .about-timeline__track {
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    padding-top: 42px;
  }

  .page-about .about-timeline__track::before {
    content: "";
    left: 2%;
    right: 2%;
    top: 8px;
    bottom: auto;
    width: auto;
    height: 2px;
    background: linear-gradient(90deg, var(--about-gold), var(--about-red));
  }

  .page-about .about-timeline__entry {
    padding-left: 0;
    display: flex;
    flex-direction: column;
  }

  .page-about .about-timeline__dot {
    left: 0;
    top: 0;
  }

  .page-about .about-timeline__summary {
    flex-direction: column;
    align-items: flex-start;
    gap: 2px;
    padding-top: 28px;
    padding-bottom: 8px;
  }

  .page-about .about-timeline__title {
    font-size: 16px;
  }

  .page-about .about-timeline__content {
    border-left: 0;
    border-top: 2px solid var(--about-gold);
    margin-top: 6px;
  }

  .page-about .about-services__grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about .about-services__card--visitor {
    grid-row: auto;
  }

  .page-about .about-tech__item {
    grid-template-columns: 60px 1fr;
    gap: 4px 18px;
  }
}

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

  .page-about .about-philosophy__item,
  .page-about .about-services__card,
  .page-about .about-tech__item,
  .page-about .about-timeline__entry {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
}