.page-about {
  --about-gold-light: #FFE08A;
  --about-red-deep: #C62828;
  --about-line-thin: 1px solid rgba(255, 215, 0, 0.3);
  --about-spacing-lg: 5rem;
  --about-spacing-md: 3rem;
  --about-spacing-sm: 1.5rem;
  --about-font-size-hero: clamp(3.2rem, 10vw, 6rem);
  --about-font-size-lg: clamp(1.8rem, 4vw, 2.8rem);
  --about-font-size-md: clamp(1rem, 1.6vw, 1.15rem);

  background-color: var(--background-dark, #0D0D0D);
  color: var(--text-light, #F5F5F5);
}

/* ===== 面包屑 ===== */
.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem 0.6rem;
  padding-top: 1.2rem;
  padding-bottom: 0.6rem;
  font-family: var(--font-small, 'Noto Sans SC', sans-serif);
  font-size: 0.75rem;
  font-weight: 300;
  letter-spacing: 0.04em;
  color: rgba(245, 245, 245, 0.5);
}

.page-about .breadcrumb a {
  color: var(--primary-gold, #FFD700);
  text-decoration: none;
  transition: opacity 0.25s;
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  opacity: 0.7;
  outline: 2px solid var(--primary-gold, #FFD700);
  outline-offset: 2px;
}

.page-about .breadcrumb__sep {
  color: rgba(255, 215, 0, 0.35);
}

.page-about .breadcrumb span[aria-current="page"] {
  color: rgba(245, 245, 245, 0.7);
  font-weight: 400;
}

/* ===== 首屏 ===== */
.page-about .about-hero {
  position: relative;
  min-height: 82vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  margin-bottom: var(--about-spacing-lg, 5rem);
}

.page-about .about-hero__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 30%;
  z-index: 0;
}

.page-about .about-hero__overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg,
    rgba(13, 13, 13, 0.85) 0%,
    rgba(13, 13, 13, 0.55) 45%,
    rgba(230, 57, 70, 0.3) 100%
  );
  z-index: 1;
}

.page-about .about-hero__particle {
  position: absolute;
  width: 6px;
  height: 6px;
  background: var(--primary-gold, #FFD700);
  border-radius: 50%;
  z-index: 2;
  opacity: 0.25;
  animation: aboutParticleFloat 6s ease-in-out infinite;
  pointer-events: none;
}

.page-about .about-hero__particle--2 {
  width: 10px;
  height: 10px;
  top: 18%;
  right: 12%;
  animation-delay: 2.4s;
  opacity: 0.18;
}

.page-about .about-hero__particle--3 {
  width: 7px;
  height: 7px;
  bottom: 22%;
  left: 8%;
  animation-delay: 4.2s;
  opacity: 0.2;
}

@keyframes aboutParticleFloat {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(-28px) scale(1.3); }
}

.page-about .about-hero__container {
  position: relative;
  z-index: 3;
  width: 100%;
}

.page-about .about-hero__content {
  max-width: 720px;
  padding: 2rem 0;
}

.page-about .about-hero__label {
  display: inline-block;
  font-family: var(--font-small, 'Noto Sans SC', sans-serif);
  font-size: 0.75rem;
  font-weight: 300;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: var(--primary-gold, #FFD700);
  border: 1px solid rgba(255, 215, 0, 0.35);
  padding: 0.3rem 0.9rem;
  margin-bottom: 1.4rem;
}

.page-about .about-hero__title {
  font-family: var(--font-heading, 'STKaiti', 'KaiTi', serif);
  font-size: var(--about-font-size-hero);
  font-weight: 900;
  line-height: 1.1;
  color: var(--text-light, #F5F5F5);
  margin: 0 0 0.5rem;
  text-shadow: 0 2px 20px rgba(230, 57, 70, 0.3);
}

.page-about .about-hero__divider {
  width: 80px;
  height: 3px;
  background: var(--gold-gradient, linear-gradient(135deg, #FFD700, #E6C300));
  margin: 1.2rem 0 1.6rem;
  border-radius: 2px;
}

.page-about .about-hero__statement {
  font-family: var(--font-body, 'Noto Sans SC', sans-serif);
  font-size: var(--about-font-size-md);
  font-weight: 300;
  line-height: 1.6;
  color: rgba(245, 245, 245, 0.85);
  max-width: 540px;
  margin: 0 0 2.2rem;
}

.page-about .about-hero__meta {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-small, 'Noto Sans SC', sans-serif);
  font-size: 0.7rem;
  font-weight: 300;
  letter-spacing: 0.12em;
  color: rgba(255, 215, 0, 0.6);
}

.page-about .about-hero__meta-line {
  text-transform: uppercase;
}

.page-about .about-hero__meta-dot {
  width: 4px;
  height: 4px;
  background: var(--primary-gold, #FFD700);
  border-radius: 50%;
  opacity: 0.5;
}

.page-about .about-hero__meta-num {
  font-weight: 400;
  color: var(--primary-gold, #FFD700);
}

/* ===== 理念区 ===== */
.page-about .about-mission {
  padding: 0 0 var(--about-spacing-lg, 5rem);
}

.page-about .about-mission__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  align-items: center;
}

.page-about .about-mission__text {
  order: 2;
}

.page-about .about-mission__heading {
  font-family: var(--font-heading, 'STKaiti', 'KaiTi', serif);
  font-size: var(--about-font-size-lg);
  font-weight: 900;
  color: var(--primary-gold, #FFD700);
  margin: 0 0 0.8rem;
  line-height: 1.2;
}

.page-about .about-mission__lead {
  font-size: 1.05rem;
  font-weight: 400;
  color: rgba(245, 245, 245, 0.9);
  line-height: 1.6;
  margin: 0 0 0.4rem;
}

.page-about .about-mission__divider {
  width: 50px;
  height: 2px;
  background: var(--gold-gradient, linear-gradient(135deg, #FFD700, #E6C300));
  margin: 1.2rem 0;
  border-radius: 2px;
}

.page-about .about-mission__body {
  font-size: var(--about-font-size-md);
  font-weight: 300;
  line-height: 1.8;
  color: rgba(245, 245, 245, 0.75);
  margin: 0 0 1rem;
}

.page-about .about-mission__cta {
  display: inline-block;
  margin-top: 0.8rem;
}

.page-about .about-mission__visual {
  order: 1;
  display: flex;
  justify-content: center;
}

.page-about .about-mission__frame {
  position: relative;
  width: 100%;
  max-width: 380px;
  aspect-ratio: 1 / 1;
  border: 2px solid var(--border-gold, #B8860B);
  padding: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(26, 26, 26, 0.6);
}

.page-about .about-mission__frame::before {
  content: '';
  position: absolute;
  inset: 6px;
  border: 1px solid rgba(255, 215, 0, 0.2);
  pointer-events: none;
}

.page-about .about-mission__frame-label {
  position: absolute;
  top: -0.5rem;
  left: 1.2rem;
  background: var(--background-dark, #0D0D0D);
  padding: 0 0.6rem;
  font-family: var(--font-heading, 'STKaiti', 'KaiTi', serif);
  font-size: 0.8rem;
  color: var(--primary-gold, #FFD700);
  letter-spacing: 0.15em;
  z-index: 1;
}

.page-about .about-mission__pattern {
  width: 70%;
  height: 70%;
  background:
    repeating-linear-gradient(45deg,
      transparent,
      transparent 12px,
      rgba(255, 215, 0, 0.07) 12px,
      rgba(255, 215, 0, 0.07) 14px
    ),
    repeating-linear-gradient(-45deg,
      transparent,
      transparent 12px,
      rgba(255, 215, 0, 0.07) 12px,
      rgba(255, 215, 0, 0.07) 14px
    );
  border: 1px solid rgba(255, 215, 0, 0.15);
}

.page-about .about-mission__pattern--rev {
  position: absolute;
  width: 40%;
  height: 40%;
  bottom: 0.6rem;
  right: 0.6rem;
  background:
    repeating-linear-gradient(135deg,
      transparent,
      transparent 8px,
      rgba(230, 57, 70, 0.08) 8px,
      rgba(230, 57, 70, 0.08) 10px
    );
  border: none;
}

/* ===== 里程碑区 ===== */
.page-about .about-milestones {
  padding: 0 0 var(--about-spacing-lg, 5rem);
  position: relative;
}

.page-about .about-milestones__title {
  text-align: center;
  margin-bottom: 0.4rem;
}

.page-about .about-milestones__visual {
  display: flex;
  justify-content: center;
  margin-top: 2.5rem;
}

.page-about .about-milestones__img {
  max-width: 100%;
  height: auto;
  border: 1px solid rgba(255, 215, 0, 0.2);
  object-fit: cover;
}

.page-about .timeline {
  position: relative;
  padding: 1.8rem 0 0.5rem;
  max-width: 720px;
  margin: 0 auto;
}

.page-about .timeline::before {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  left: 18px;
  width: 2px;
  background: linear-gradient(to bottom,
    rgba(255, 215, 0, 0.5),
    rgba(255, 215, 0, 0.15) 70%,
    transparent
  );
}

.page-about .timeline__item {
  position: relative;
  padding-left: 50px;
  margin-bottom: 2rem;
}

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

.page-about .timeline__dot {
  position: absolute;
  left: 10px;
  top: 0.6rem;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--background-dark, #0D0D0D);
  border: 3px solid var(--primary-gold, #FFD700);
  box-shadow: 0 0 0 4px rgba(255, 215, 0, 0.15);
  z-index: 1;
}

.page-about .timeline__card {
  background: var(--background-section, #1A1A1A);
  border: 1px solid rgba(255, 215, 0, 0.18);
  border-radius: 4px;
  transition: border-color 0.3s, box-shadow 0.3s;
}

.page-about .timeline__card:hover {
  border-color: rgba(255, 215, 0, 0.4);
  box-shadow: 0 4px 20px rgba(255, 215, 0, 0.06);
}

.page-about .timeline__details {
  display: block;
}

.page-about .timeline__summary {
  display: flex;
  align-items: flex-start;
  gap: 0.8rem;
  padding: 1rem 1.2rem;
  cursor: pointer;
  list-style: none;
  user-select: none;
}

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

.page-about .timeline__summary:focus-visible {
  outline: 2px solid var(--primary-gold, #FFD700);
  outline-offset: -2px;
  border-radius: 4px;
}

.page-about .timeline__marker {
  flex-shrink: 0;
  font-family: var(--font-heading, 'STKaiti', 'KaiTi', serif);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--primary-gold, #FFD700);
  line-height: 1.4;
  min-width: 1.8rem;
}

.page-about .timeline__header {
  flex: 1;
  min-width: 0;
}

.page-about .timeline__heading {
  font-family: var(--font-heading, 'STKaiti', 'KaiTi', serif);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-light, #F5F5F5);
  margin: 0 0 0.2rem;
  line-height: 1.3;
}

.page-about .timeline__brief {
  font-size: 0.82rem;
  font-weight: 300;
  color: rgba(245, 245, 245, 0.6);
  margin: 0;
  line-height: 1.4;
}

.page-about .timeline__toggle-icon {
  flex-shrink: 0;
  font-size: 1.1rem;
  font-weight: 300;
  color: var(--primary-gold, #FFD700);
  line-height: 1.4;
  transition: transform 0.3s;
}

.page-about .timeline__details[open] .timeline__toggle-icon {
  transform: rotate(45deg);
}

.page-about .timeline__expand {
  padding: 0 1.2rem 1.2rem;
  border-top: 1px solid rgba(255, 215, 0, 0.1);
  margin-top: 0;
}

.page-about .timeline__expand p {
  font-size: 0.88rem;
  font-weight: 300;
  line-height: 1.7;
  color: rgba(245, 245, 245, 0.7);
  margin: 0.8rem 0 0.6rem;
}

.page-about .timeline__link {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 400;
  color: var(--primary-gold, #FFD700);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 215, 0, 0.3);
  padding-bottom: 1px;
  transition: border-color 0.25s;
}

.page-about .timeline__link:hover,
.page-about .timeline__link:focus-visible {
  border-bottom-color: var(--primary-gold, #FFD700);
  outline: none;
}

/* ===== 承诺区 ===== */
.page-about .about-promises {
  padding: 0 0 var(--about-spacing-lg, 5rem);
}

.page-about .about-promises__title {
  text-align: center;
  margin-bottom: 0.6rem;
}

.page-about .about-promises__intro {
  text-align: center;
  font-size: var(--about-font-size-md);
  font-weight: 300;
  line-height: 1.6;
  color: rgba(245, 245, 245, 0.65);
  max-width: 600px;
  margin: 0 auto 2.5rem;
}

.page-about .about-promises__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.8rem;
}

.page-about .promise-card {
  background: var(--background-section, #1A1A1A);
  border: 1px solid rgba(255, 215, 0, 0.15);
  padding: 1.8rem 1.5rem 1.5rem;
  display: flex;
  flex-direction: column;
  transition: border-color 0.3s, transform 0.3s;
  position: relative;
}

.page-about .promise-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 1.5rem;
  right: 1.5rem;
  height: 2px;
  background: var(--gold-gradient, linear-gradient(135deg, #FFD700, #E6C300));
  opacity: 0;
  transition: opacity 0.3s;
}

.page-about .promise-card:hover,
.page-about .promise-card:focus-within {
  border-color: rgba(255, 215, 0, 0.35);
  transform: translateY(-3px);
}

.page-about .promise-card:hover::after {
  opacity: 1;
}

.page-about .promise-card__icon {
  margin-bottom: 1rem;
  max-width: 120px;
}

.page-about .promise-card__img {
  width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid rgba(255, 215, 0, 0.1);
}

.page-about .promise-card__title {
  font-family: var(--font-heading, 'STKaiti', 'KaiTi', serif);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--primary-gold, #FFD700);
  margin: 0 0 0.5rem;
}

.page-about .promise-card__text {
  font-size: 0.88rem;
  font-weight: 300;
  line-height: 1.7;
  color: rgba(245, 245, 245, 0.7);
  margin: 0 0 1.2rem;
  flex: 1;
}

.page-about .promise-card__link {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--primary-gold, #FFD700);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 215, 0, 0.2);
  align-self: flex-start;
  transition: border-color 0.25s, gap 0.25s;
}

.page-about .promise-card__link:hover,
.page-about .promise-card__link:focus-visible {
  border-bottom-color: var(--primary-gold, #FFD700);
  gap: 0.6rem;
  outline: none;
}

/* ===== 信任声明区 ===== */
.page-about .about-trust {
  padding: 0 0 var(--about-spacing-lg, 5rem);
}

.page-about .about-trust__inner {
  position: relative;
  max-width: 720px;
  margin: 0 auto;
  padding: 2.5rem 2rem;
  background: var(--background-section, #1A1A1A);
  border: 2px solid var(--border-gold, #B8860B);
  text-align: center;
  overflow: hidden;
}

.page-about .about-trust__border {
  position: absolute;
  inset: 6px;
  border: 1px solid rgba(255, 215, 0, 0.15);
  pointer-events: none;
}

.page-about .about-trust__text {
  font-size: 0.92rem;
  font-weight: 300;
  line-height: 1.8;
  color: rgba(245, 245, 245, 0.75);
  margin: 0;
  position: relative;
  z-index: 1;
}

.page-about .about-trust__seal {
  position: absolute;
  bottom: 0.4rem;
  right: 1rem;
  font-family: var(--font-heading, 'STKaiti', 'KaiTi', serif);
  font-size: 2.8rem;
  font-weight: 900;
  color: rgba(255, 215, 0, 0.06);
  line-height: 1;
  pointer-events: none;
  user-select: none;
  z-index: 0;
}

/* ===== 响应式桌面 ===== */
@media (min-width: 768px) {
  .page-about .about-hero {
    min-height: 90vh;
  }

  .page-about .about-hero__content {
    padding: 3rem 0;
  }

  .page-about .about-hero__particle {
    width: 8px;
    height: 8px;
    top: 15%;
    left: 55%;
  }

  .page-about .about-hero__particle--2 {
    width: 12px;
    height: 12px;
    top: 22%;
    right: 18%;
  }

  .page-about .about-hero__particle--3 {
    width: 9px;
    height: 9px;
    bottom: 20%;
    left: 12%;
  }

  .page-about .about-mission__grid {
    grid-template-columns: 1fr 1fr;
    gap: 3.5rem;
  }

  .page-about .about-mission__text {
    order: 1;
  }

  .page-about .about-mission__visual {
    order: 2;
    justify-content: flex-end;
  }

  .page-about .about-mission__frame {
    max-width: 340px;
    padding: 1.5rem;
  }

  .page-about .timeline {
    padding-left: 2rem;
    padding-right: 2rem;
  }

  .page-about .timeline::before {
    left: 50%;
    transform: translateX(-50%);
  }

  .page-about .timeline__item {
    padding-left: 0;
    margin-bottom: 2.5rem;
  }

  .page-about .timeline__item:nth-child(odd) {
    padding-right: calc(50% + 30px);
    text-align: right;
  }

  .page-about .timeline__item:nth-child(even) {
    padding-left: calc(50% + 30px);
    text-align: left;
  }

  .page-about .timeline__dot {
    left: 50%;
    transform: translateX(-50%);
    top: 0.8rem;
  }

  .page-about .timeline__summary {
    flex-direction: row;
  }

  .page-about .timeline__item:nth-child(odd) .timeline__summary {
    flex-direction: row-reverse;
  }

  .page-about .timeline__item:nth-child(odd) .timeline__toggle-icon {
    order: 0;
  }

  .page-about .timeline__item:nth-child(odd) .timeline__marker {
    order: 2;
  }

  .page-about .timeline__item:nth-child(even) .timeline__summary {
    flex-direction: row;
  }

  .page-about .timeline__expand {
    text-align: left;
  }

  .page-about .about-promises__grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
  }

  .page-about .promise-card {
    padding: 2rem 1.8rem 1.8rem;
  }

  .page-about .about-trust__inner {
    padding: 3rem 3rem;
  }

  .page-about .about-trust__seal {
    font-size: 4rem;
    bottom: 0.2rem;
    right: 1.5rem;
  }
}

@media (min-width: 1024px) {
  .page-about .about-hero__title {
    font-size: 6rem;
  }

  .page-about .about-mission__frame {
    max-width: 380px;
  }

  .page-about .about-promises__grid {
    gap: 2.5rem;
  }
}

/* ===== 容器复用 ===== */
.page-about .container {
  max-width: var(--container-max, 1200px);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.2rem;
  padding-right: 1.2rem;
}

@media (min-width: 768px) {
  .page-about .container {
    padding-left: 2rem;
    padding-right: 2rem;
  }
}

/* ===== 共享类调整（仅限本页覆盖） ===== */
.page-about .section-title {
  font-family: var(--font-heading, 'STKaiti', 'KaiTi', serif);
  font-size: clamp(1.6rem, 3.6vw, 2.4rem);
  font-weight: 900;
  color: var(--primary-gold, #FFD700);
  margin: 0 0 0.8rem;
  padding-bottom: 0.6rem;
  border-bottom: 2px solid rgba(255, 215, 0, 0.2);
  position: relative;
}

.page-about .section-title::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 60px;
  height: 2px;
  background: var(--gold-gradient, linear-gradient(135deg, #FFD700, #E6C300));
}

.page-about .btn-gold {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.65rem 1.6rem;
  font-family: var(--font-body, 'Noto Sans SC', sans-serif);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-dark, #222222);
  background: var(--gold-gradient, linear-gradient(135deg, #FFD700, #E6C300));
  border: none;
  border-radius: 2px;
  text-decoration: none;
  cursor: pointer;
  transition: opacity 0.3s, transform 0.25s;
  letter-spacing: 0.04em;
}

.page-about .btn-gold:hover,
.page-about .btn-gold:focus-visible {
  opacity: 0.88;
  transform: translateY(-1px);
  outline: 2px solid var(--primary-gold, #FFD700);
  outline-offset: 3px;
}

/* ===== 溢出保护 ===== */
.page-about img {
  max-width: 100%;
  height: auto;
  display: block;
}

.page-about * {
  box-sizing: border-box;
}