/* 手机优先 — 品牌介绍页专属样式 */
.page-about {
  --about-accent-angle: -6deg;
  --about-num-size: 5rem;
  --about-num-size-md: 8rem;
  --about-num-size-lg: 10rem;
}

/* ─── 首屏 HERO ─── */
.page-about .about-hero {
  position: relative;
  min-height: 85vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background-color: var(--bg-dark, #121212);
}

.page-about .about-hero__visual {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.page-about .about-hero__img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 30%;
}

.page-about .about-hero__overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(18,18,18,0.85) 30%, rgba(18,18,18,0.40) 70%);
}

.page-about .about-hero__accent {
  position: absolute;
  top: 0;
  right: -10%;
  width: 45%;
  height: 100%;
  background: var(--color-red, #D32F2F);
  transform: skewX(var(--about-accent-angle));
  opacity: 0.35;
  z-index: 1;
  pointer-events: none;
}

.page-about .about-hero__content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 2rem 1.5rem;
  max-width: 720px;
}

.page-about .about-hero__label {
  display: inline-block;
  font-family: var(--heading-font, 'Bebas Neue', Impact, sans-serif);
  font-size: 1rem;
  letter-spacing: 0.25em;
  color: var(--color-yellow, #FBC02D);
  border: 2px solid var(--color-yellow, #FBC02D);
  padding: 0.3rem 1.2rem;
  margin-bottom: 1.5rem;
  text-transform: uppercase;
}

.page-about .about-hero__title {
  font-family: var(--heading-font, 'Bebas Neue', Impact, sans-serif);
  font-size: clamp(3.2rem, 12vw, 7rem);
  font-weight: 700;
  line-height: 0.92;
  color: var(--text-primary, #fff);
  margin: 0 0 0.6rem;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.page-about .about-hero__subtitle {
  font-family: var(--body-font, 'Inter', Roboto, sans-serif);
  font-size: clamp(1rem, 3vw, 1.6rem);
  font-weight: 400;
  color: var(--color-silver, #B0BEC5);
  margin: 0;
  letter-spacing: 0.15em;
}

.page-about .about-hero__scroll {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 3;
  color: var(--color-silver, #B0BEC5);
  font-size: 1.4rem;
  animation: about-bounce 2s infinite;
}

@keyframes about-bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}

/* ─── 章节通用 ─── */
.page-about .about-section {
  padding: 4rem 1.5rem;
  background-color: var(--bg-dark, #121212);
}

.page-about .about-section--alt {
  background-color: var(--bg-card, #1E1E1E);
}

.page-about .about-section__inner {
  max-width: var(--container-max, 1280px);
  margin: 0 auto;
}

.page-about .about-section__num {
  font-family: var(--heading-font, 'Bebas Neue', Impact, sans-serif);
  font-size: var(--about-num-size);
  font-weight: 700;
  line-height: 1;
  color: var(--color-red, #D32F2F);
  opacity: 0.5;
  margin-bottom: 0.25rem;
  user-select: none;
}

.page-about .about-section__title {
  font-family: var(--heading-font, 'Bebas Neue', Impact, sans-serif);
  font-size: clamp(1.8rem, 5vw, 3rem);
  font-weight: 700;
  line-height: 1.05;
  color: var(--text-primary, #fff);
  margin: 0 0 0.75rem;
  text-transform: uppercase;
}

.page-about .about-section__desc {
  font-family: var(--body-font, 'Inter', Roboto, sans-serif);
  font-size: 1.05rem;
  color: var(--color-yellow, #FBC02D);
  font-weight: 500;
  margin: 0 0 1.2rem;
  max-width: 540px;
}

.page-about .about-section__text {
  font-family: var(--body-font, 'Inter', Roboto, sans-serif);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text-secondary, #B0BEC5);
  margin: 0;
  max-width: 620px;
}

/* ─── 分隔装饰 ─── */
.page-about .about-divider {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 1rem 1.5rem;
  background-color: var(--bg-dark, #121212);
}

.page-about .about-divider__img {
  display: block;
  width: 100%;
  max-width: 120px;
  height: auto;
  opacity: 0.7;
}

/* ─── 服务卡片网格 ─── */
.page-about .service-grid {
  display: grid;
  gap: 1.25rem;
  margin-top: 2rem;
}

.page-about .service-card {
  background-color: var(--bg-card, #1E1E1E);
  border: 2px solid var(--color-silver, #B0BEC5);
  box-shadow: var(--shadow-strong, 0 8px 24px rgba(0,0,0,0.6));
  transition: border-color 0.25s, transform 0.25s;
  overflow: hidden;
}

.page-about .service-card[open] {
  border-color: var(--color-red, #D32F2F);
}

.page-about .service-card__summary {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.25rem;
  cursor: pointer;
  list-style: none;
}

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

.page-about .service-card__icon {
  font-size: 2rem;
  flex-shrink: 0;
  width: 2.4rem;
  text-align: center;
  line-height: 1;
}

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

.page-about .service-card__name {
  font-family: var(--heading-font, 'Bebas Neue', Impact, sans-serif);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary, #fff);
  margin: 0 0 0.15rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.page-about .service-card__brief {
  font-family: var(--body-font, 'Inter', Roboto, sans-serif);
  font-size: 0.85rem;
  color: var(--text-secondary, #B0BEC5);
  margin: 0;
}

.page-about .service-card__chevron {
  font-size: 0.9rem;
  color: var(--color-silver, #B0BEC5);
  transition: transform 0.3s;
  flex-shrink: 0;
}

.page-about .service-card[open] .service-card__chevron {
  transform: rotate(90deg);
  color: var(--color-red, #D32F2F);
}

.page-about .service-card__detail {
  padding: 0 1.25rem 1.25rem;
  border-top: 1px solid var(--color-silver, #B0BEC5);
  margin-top: 0;
}

.page-about .service-card__detail p {
  font-family: var(--body-font, 'Inter', Roboto, sans-serif);
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--text-secondary, #B0BEC5);
  margin: 0.75rem 0 1rem;
}

.page-about .service-card__detail .btn {
  display: inline-block;
  padding: 0.4rem 1.5rem;
  background-color: var(--color-red, #D32F2F);
  color: var(--text-primary, #fff);
  font-family: var(--heading-font, 'Bebas Neue', Impact, sans-serif);
  font-size: 1rem;
  letter-spacing: 0.08em;
  text-decoration: none;
  text-transform: uppercase;
  border: 2px solid var(--color-red, #D32F2F);
  transition: background-color 0.2s, color 0.2s;
}

.page-about .service-card__detail .btn:hover,
.page-about .service-card__detail .btn:focus-visible {
  background-color: transparent;
  color: var(--color-red, #D32F2F);
}

/* ─── 优势列表 ─── */
.page-about .benefits-wrap {
  display: grid;
  gap: 2rem;
  margin-top: 2rem;
}

.page-about .benefits-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.page-about .benefits-list__item {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.page-about .benefits-list__marker {
  flex-shrink: 0;
  width: 12px;
  height: 12px;
  margin-top: 0.4rem;
  background-color: var(--color-blue, #2196F3);
  transform: rotate(45deg);
}

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

.page-about .benefits-list__label {
  display: block;
  font-family: var(--heading-font, 'Bebas Neue', Impact, sans-serif);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-primary, #fff);
  letter-spacing: 0.04em;
  margin-bottom: 0.2rem;
  text-transform: uppercase;
}

.page-about .benefits-list__text {
  font-family: var(--body-font, 'Inter', Roboto, sans-serif);
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--text-secondary, #B0BEC5);
  margin: 0;
}

.page-about .benefits-fig {
  border: 2px solid var(--color-silver, #B0BEC5);
  box-shadow: var(--shadow-strong, 0 8px 24px rgba(0,0,0,0.6));
  overflow: hidden;
}

.page-about .benefits-fig__img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ─── 结尾联系 ─── */
.page-about .about-outro {
  padding: 3rem 1.5rem;
  background-color: var(--bg-dark, #121212);
  border-top: 2px solid var(--color-red, #D32F2F);
}

.page-about .about-outro__inner {
  max-width: var(--container-max, 1280px);
  margin: 0 auto;
  text-align: center;
}

.page-about .about-outro__text {
  font-family: var(--body-font, 'Inter', Roboto, sans-serif);
  font-size: 1.05rem;
  color: var(--text-primary, #fff);
  margin: 0 0 1rem;
}

.page-about .about-outro__btn {
  display: inline-block;
  padding: 0.6rem 2.2rem;
  background-color: transparent;
  color: var(--color-yellow, #FBC02D);
  font-family: var(--heading-font, 'Bebas Neue', Impact, sans-serif);
  font-size: 1.2rem;
  letter-spacing: 0.08em;
  text-decoration: none;
  text-transform: uppercase;
  border: 2px solid var(--color-yellow, #FBC02D);
  transition: background-color 0.25s, color 0.25s;
}

.page-about .about-outro__btn:hover,
.page-about .about-outro__btn:focus-visible {
  background-color: var(--color-yellow, #FBC02D);
  color: var(--bg-dark, #121212);
}

.page-about .about-outro__note {
  font-family: var(--body-font, 'Inter', Roboto, sans-serif);
  font-size: 0.8rem;
  color: var(--text-secondary, #B0BEC5);
  margin: 1.2rem 0 0;
  opacity: 0.6;
}

/* ─── 桌面端 768px+ ─── */
@media (min-width: 768px) {
  .page-about {
    --about-num-size: var(--about-num-size-md);
  }

  .page-about .about-hero {
    min-height: 75vh;
  }

  .page-about .about-hero__accent {
    width: 38%;
    right: -8%;
  }

  .page-about .about-hero__content {
    text-align: left;
    padding: 2rem 4rem;
    max-width: 820px;
    margin-right: auto;
    margin-left: 5%;
  }

  .page-about .about-hero__title {
    font-size: clamp(4.5rem, 9vw, 8rem);
  }

  .page-about .about-hero__label {
    margin-bottom: 2rem;
  }

  .page-about .about-hero__scroll {
    bottom: 2.5rem;
  }

  .page-about .about-section {
    padding: 5rem 2.5rem;
  }

  .page-about .about-section__inner {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 2.5rem;
  }

  .page-about .about-section__num {
    font-size: var(--about-num-size-md);
    line-height: 0.85;
    position: sticky;
    top: 2rem;
    align-self: start;
    margin-bottom: 0;
  }

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

  .page-about .about-section__title {
    font-size: clamp(2rem, 4vw, 3.2rem);
  }

  .page-about .service-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
  }

  .page-about .service-card__summary {
    flex-direction: column;
    text-align: center;
    padding: 1.5rem 1rem;
  }

  .page-about .service-card__icon {
    font-size: 2.6rem;
    width: auto;
  }

  .page-about .service-card__chevron {
    display: none;
  }

  .page-about .service-card__detail {
    padding: 0 1.5rem 1.5rem;
  }

  .page-about .benefits-wrap {
    grid-template-columns: 1fr 1fr;
    align-items: center;
  }

  .page-about .benefits-list {
    gap: 1.8rem;
  }

  .page-about .benefits-list__label {
    font-size: 1.3rem;
  }

  .page-about .about-outro {
    padding: 4rem 2.5rem;
  }

  .page-about .about-outro__text {
    font-size: 1.15rem;
  }
}

/* ─── 大屏 1024px+ ─── */
@media (min-width: 1024px) {
  .page-about {
    --about-num-size: var(--about-num-size-lg);
  }

  .page-about .about-hero__content {
    margin-left: 8%;
    max-width: 900px;
  }

  .page-about .about-hero__title {
    font-size: clamp(6rem, 8vw, 10rem);
  }

  .page-about .about-section {
    padding: 6rem 3rem;
  }

  .page-about .about-section__inner {
    gap: 3.5rem;
  }

  .page-about .about-section__num {
    font-size: var(--about-num-size-lg);
  }

  .page-about .about-section__desc {
    font-size: 1.15rem;
  }

  .page-about .service-grid {
    gap: 2rem;
  }

  .page-about .about-outro {
    padding: 5rem 3rem;
  }
}

/* ─── 滚动渐入交互（渐进增强） ─── */
.page-about [data-scroll-reveal] {
  opacity: 1;
  transform: translateY(0);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

/* 若JS启用，可用此钩子触发动画，默认完全可见 */
@media (prefers-reduced-motion: no-preference) {
  .page-about [data-scroll-reveal] {
    opacity: 0.99;
    transform: translateY(12px);
  }
}