.page-about {
  background: var(--ybo-light);
  color: var(--ybo-text);
  font-family: var(--ybo-font-body);
  line-height: 1.6;
  overflow-x: hidden;
}

.page-about .about-container {
  max-width: var(--ybo-container-w);
  margin: 0 auto;
  padding: 0 clamp(18px, 4vw, 32px);
}

.page-about [id^="section-"] {
  scroll-margin-top: calc(var(--ybo-header-h) + 16px);
}

.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--ybo-neon);
  outline-offset: 3px;
}

/* 首屏品牌宣言 */
.page-about .about-hero {
  position: relative;
  display: flex;
  align-items: center;
  min-height: 76vh;
  padding: clamp(56px, 8vw, 88px) 0;
  background: var(--ybo-deep);
  color: var(--ybo-ondark);
  overflow: hidden;
}

.page-about .about-hero__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.45;
  z-index: 0;
}

.page-about .about-hero__overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(100deg, rgba(10, 31, 68, 0.82) 0%, rgba(10, 31, 68, 0.55) 62%, rgba(10, 31, 68, 0.22) 100%);
  z-index: 1;
}

.page-about .about-hero__inner {
  width: 100%;
  z-index: 2;
}

.page-about .about-breadcrumb {
  display: flex;
  gap: 8px;
  margin-bottom: 22px;
  color: rgba(229, 231, 235, 0.68);
}

.page-about .about-breadcrumb .ybo-breadcrumb__list {
  display: flex;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--ybo-font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.page-about .about-breadcrumb a {
  color: var(--ybo-neon);
  text-decoration: none;
}

.page-about .about-hero__title {
  font-family: var(--ybo-font-head);
  font-size: clamp(30px, 5vw, 52px);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.02em;
  margin: 0 0 20px;
  max-width: 16em;
}

.page-about .about-hero__lead {
  font-size: clamp(15px, 1.7vw, 17px);
  font-weight: 300;
  line-height: 1.8;
  color: rgba(229, 231, 235, 0.82);
  max-width: 46em;
  margin: 0 0 32px;
}

.page-about .about-hero__index {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-hero__index a {
  border: 1px solid rgba(57, 255, 20, 0.38);
  border-radius: 999px;
  padding: 8px 18px;
  font-family: var(--ybo-font-mono);
  font-size: 13px;
  color: #fff;
  text-decoration: none;
  transition: background 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}

.page-about .about-hero__index a:hover {
  background: rgba(57, 255, 20, 0.12);
  border-color: var(--ybo-neon);
  transform: translateY(-2px);
}

/* 编号章节通用 */
.page-about .about-chapter {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  margin-bottom: 36px;
}

.page-about .about-chapter .ybo-chapter__num {
  line-height: 1;
  font-size: clamp(48px, 6vw, 72px);
  flex-shrink: 0;
  color: rgba(10, 31, 68, 0.14);
  -webkit-text-stroke: 1.2px var(--ybo-deep);
}

.page-about .about-chapter__head {
  padding-top: 4px;
}

.page-about .about-chapter__title {
  font-family: var(--ybo-font-head);
  font-weight: 800;
  font-size: clamp(26px, 3.6vw, 38px);
  letter-spacing: -0.02em;
  color: var(--ybo-deep);
  margin: 0 0 6px;
}

.page-about .about-chapter__sub {
  font-family: var(--ybo-font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #6b7280;
  margin: 0;
}

.page-about .about-chapter--dark .ybo-chapter__num {
  color: rgba(57, 255, 20, 0.2);
  -webkit-text-stroke-color: var(--ybo-neon);
}

.page-about .about-chapter--dark .about-chapter__title {
  color: #fff;
}

.page-about .about-chapter--dark .about-chapter__sub {
  color: rgba(255, 255, 255, 0.55);
}

/* 01 我们是谁 */
.page-about .about-who {
  padding: clamp(52px, 8vw, 96px) 0;
}

.page-about .about-who__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
}

.page-about .about-who__content p {
  font-size: 16px;
  font-weight: 300;
  line-height: 1.75;
  color: #334155;
  margin: 0 0 18px;
}

.page-about .about-who__side {
  position: relative;
  overflow: hidden;
  border-radius: var(--ybo-radius);
  background: var(--ybo-deep);
  color: var(--ybo-ondark);
  padding: 30px;
}

.page-about .about-who__side::before {
  content: "";
  position: absolute;
  right: -44px;
  bottom: -44px;
  width: 180px;
  height: 180px;
  border-radius: 50%;
  background: var(--ybo-neon);
  opacity: 0.1;
  filter: blur(40px);
}

.page-about .about-who__card {
  position: relative;
  display: grid;
  gap: 6px;
  padding-bottom: 20px;
  margin-bottom: 18px;
  border-bottom: 1px solid rgba(229, 231, 235, 0.16);
}

.page-about .about-who__card-label {
  font-family: var(--ybo-font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ybo-mgray);
}

.page-about .about-who__card-value {
  font-family: var(--ybo-font-mono);
  font-size: 18px;
  color: var(--ybo-neon);
}

.page-about .about-who__note {
  font-size: 14px;
  font-weight: 300;
  color: rgba(229, 231, 235, 0.72);
  line-height: 1.7;
  margin: 0 0 24px;
  position: relative;
}

.page-about .about-who__side .ybo-btn {
  position: relative;
}

@media (min-width: 900px) {
  .page-about .about-who__grid {
    grid-template-columns: 7fr 5fr;
    align-items: start;
    gap: 48px;
  }
}

/* 02 关键数字 */
.page-about .about-stats {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 88% 12%, rgba(57, 255, 20, 0.14), transparent 32%),
    radial-gradient(circle at 10% 90%, rgba(255, 107, 53, 0.1), transparent 34%),
    var(--ybo-deep);
  color: var(--ybo-ondark);
  padding: clamp(56px, 9vw, 110px) 0;
}

.page-about .about-stats__head {
  margin-bottom: 40px;
}

.page-about .about-stats__intro {
  font-size: 15px;
  font-weight: 300;
  line-height: 1.75;
  color: rgba(229, 231, 235, 0.72);
  max-width: 38em;
  margin: 0;
}

.page-about .about-stats__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  align-items: center;
}

.page-about .about-stats__visual img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 8 / 5;
  object-fit: cover;
  border-radius: var(--ybo-radius);
  box-shadow: var(--ybo-shadow-lg);
}

.page-about .about-stats__numbers {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px 20px;
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--ybo-font-head);
  font-weight: 800;
  font-size: clamp(30px, 5vw, 48px);
  line-height: 1;
  color: var(--ybo-neon);
}

.page-about .about-stat__unit {
  margin-left: 4px;
  font-size: 0.44em;
  font-weight: 400;
  color: rgba(255, 255, 255, 0.6);
}

.page-about .about-stat__label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.5;
  color: rgba(229, 231, 235, 0.72);
  font-weight: 300;
}

@media (min-width: 900px) {
  .page-about .about-stats__head {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    gap: 32px;
  }

  .page-about .about-stats__intro {
    margin: 0 0 6px;
    text-align: right;
  }

  .page-about .about-stats__grid {
    grid-template-columns: 5fr 7fr;
    gap: 48px;
  }

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

/* 03 发展历程 */
.page-about .about-history {
  padding: clamp(56px, 9vw, 108px) 0;
  background: linear-gradient(180deg, #ffffff 0%, var(--ybo-light) 100%);
}

.page-about .about-timeline {
  position: relative;
  margin-top: 52px;
}

.page-about .about-timeline__line {
  position: absolute;
  top: 6px;
  bottom: 20px;
  left: 18px;
  width: 2px;
  background: linear-gradient(to bottom, var(--ybo-neon), var(--ybo-border-green));
  opacity: 0.32;
  animation: aboutPulse 3.6s ease-in-out infinite;
}

@keyframes aboutPulse {
  0%, 100% {
    opacity: 0.22;
  }
  50% {
    opacity: 0.5;
  }
}

.page-about .about-timeline__item {
  position: relative;
  padding-left: 56px;
  padding-bottom: 28px;
}

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

.page-about .about-timeline__summary {
  display: inline-block;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-timeline__dot {
  position: absolute;
  top: 6px;
  left: 11px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--ybo-neon);
  box-shadow: 0 0 0 4px rgba(57, 255, 20, 0.18);
}

.page-about .about-timeline__period {
  display: block;
  font-family: var(--ybo-font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ybo-orange);
  margin-bottom: 5px;
}

.page-about .about-timeline__title {
  display: inline;
  font-family: var(--ybo-font-head);
  font-weight: 700;
  font-size: 18px;
  color: var(--ybo-deep);
}

.page-about .about-timeline__summary::after {
  content: "+";
  display: inline-block;
  margin-left: 8px;
  font-family: var(--ybo-font-mono);
  font-size: 15px;
  color: var(--ybo-neon);
  transition: transform 0.2s ease;
  vertical-align: middle;
}

.page-about .about-timeline__item[open] .about-timeline__summary::after {
  transform: rotate(45deg);
}

.page-about .about-timeline__item p {
  margin: 12px 0 0;
  font-size: 14px;
  font-weight: 300;
  line-height: 1.7;
  color: #475569;
  max-width: 30em;
}

.page-about .about-history__foot {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 40px;
  padding-top: 28px;
  border-top: 1px solid rgba(138, 143, 152, 0.25);
}

.page-about .about-history__foot p {
  margin: 0 auto 0 0;
  font-size: 14px;
  color: #475569;
}

@media (min-width: 860px) {
  .page-about .about-timeline {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-top: 64px;
  }

  .page-about .about-timeline__line {
    top: 20px;
    bottom: auto;
    left: 0;
    right: 0;
    width: auto;
    height: 2px;
    background: linear-gradient(to right, var(--ybo-neon), var(--ybo-border-green));
    opacity: 0.3;
  }

  .page-about .about-timeline__item {
    padding-left: 0;
    padding-top: 34px;
    padding-bottom: 0;
  }

  .page-about .about-timeline__dot {
    top: 13px;
    left: 0;
  }

  .page-about .about-timeline__item--down {
    margin-top: 64px;
  }
}

/* 04 服务承诺 */
.page-about .about-promise {
  padding: clamp(56px, 9vw, 108px) 0;
  background: #fff;
}

.page-about .about-promise__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
}

.page-about .about-promise__visual img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 8 / 5;
  object-fit: cover;
  border-radius: var(--ybo-radius);
  box-shadow: var(--ybo-shadow);
}

.page-about .about-promise__items {
  display: grid;
  gap: 14px;
}

.page-about .about-promise__item {
  display: grid;
  grid-template-columns: 44px 1fr;
  column-gap: 14px;
  padding: 22px 24px;
  background: var(--ybo-light);
  border-left: 3px solid var(--ybo-neon);
  border-radius: 0 var(--ybo-radius-sm) var(--ybo-radius-sm) 0;
  transition: background 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.page-about .about-promise__item:hover {
  background: #fff;
  transform: translateX(5px);
  box-shadow: var(--ybo-shadow);
}

.page-about .about-promise__num {
  grid-row: 1 / span 2;
  font-family: var(--ybo-font-mono);
  font-size: 20px;
  line-height: 1;
  color: var(--ybo-orange);
  padding-top: 3px;
}

.page-about .about-promise__item-title {
  font-family: var(--ybo-font-head);
  font-size: 17px;
  font-weight: 700;
  color: var(--ybo-deep);
  margin: 0 0 6px;
}

.page-about .about-promise__item-text {
  grid-column: 2;
  margin: 0;
  font-size: 14px;
  font-weight: 300;
  line-height: 1.65;
  color: #475569;
}

.page-about .about-promise__foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-top: 44px;
  padding-top: 32px;
  border-top: 1px solid #e5e7eb;
}

.page-about .about-promise__foot p {
  margin: 0 auto 0 0;
  font-size: 14px;
  color: #475569;
}

@media (min-width: 900px) {
  .page-about .about-promise__grid {
    grid-template-columns: 5fr 7fr;
    gap: 52px;
  }
}