*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

:root {
  --bb-navy: #0A1F44;
  --bb-navy-deep: #071C38;
  --bb-gold: #D4AF37;
  --bb-neon: #39FF14;
  --bb-card: #0D2A4D;
  --bb-card-float: #12315A;
  --bb-text: #FFFFFF;
  --bb-mut: #A0B0D0;
  --bb-grid: #1E3A6D;
  --bb-font-display: 'Anton', 'Impact', 'Noto Sans SC', 'PingFang SC', sans-serif;
  --bb-font-body: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --bb-container: 1200px;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-family: var(--bb-font-body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--bb-text);
  background-color: var(--bb-navy);
  background-image:
    radial-gradient(circle at 82% 12%, rgba(212, 175, 55, 0.08), transparent 28rem),
    radial-gradient(circle at 8% 42%, rgba(57, 255, 20, 0.05), transparent 24rem),
    linear-gradient(to right, var(--bb-grid) 1px, transparent 1px),
    linear-gradient(to bottom, var(--bb-grid) 1px, transparent 1px);
  background-size: auto, auto, 56px 56px, 56px 56px;
}

img,
svg {
  display: block;
  max-width: 100%;
}

ul,
ol {
  list-style: none;
}

a {
  color: inherit;
}

button {
  font: inherit;
  color: inherit;
}

::selection {
  background: var(--bb-gold);
  color: var(--bb-navy);
}

:focus-visible {
  outline: 2px solid var(--bb-neon);
  outline-offset: 2px;
}

main {
  flex: 1 0 auto;
  width: 100%;
  position: relative;
  z-index: 1;
  scroll-margin-top: 4.5rem;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 0.5rem;
  left: 0.5rem;
  z-index: 2000;
  background: var(--bb-gold);
  color: var(--bb-navy);
  padding: 0.55rem 1rem;
  font-weight: 700;
  text-decoration: none;
  transform: translateY(-200%);
  transition: transform 0.2s;
}

.skip-link:focus {
  transform: translateY(0);
}

.bb-container {
  max-width: var(--bb-container);
  margin-inline: auto;
  padding-inline: 1.25rem;
}

@media (min-width: 768px) {
  .bb-container {
    padding-inline: 2rem;
  }
}

@media (min-width: 1200px) {
  .bb-container {
    padding-inline: 2.5rem;
  }
}

.bb-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  z-index: 1000;
  background: linear-gradient(90deg, var(--bb-neon), var(--bb-gold));
  box-shadow: 0 0 12px rgba(57, 255, 20, 0.6);
}

.bb-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: linear-gradient(180deg, rgba(10, 31, 68, 0.97), rgba(13, 42, 77, 0.94));
  border-bottom: 1px solid var(--bb-grid);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.bb-header-top {
  border-bottom: 1px solid rgba(30, 58, 109, 0.7);
}

.bb-header-top-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.55rem 0.75rem;
  padding-block: 0.7rem;
}

.bb-brand {
  display: inline-flex;
  align-items: baseline;
  gap: 0.35rem;
  text-decoration: none;
  margin-right: auto;
}

.bb-brand-cn {
  font-family: var(--bb-font-display);
  font-size: clamp(1.6rem, 4vw, 2.1rem);
  line-height: 1;
  color: var(--bb-gold);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.bb-brand-en {
  font-family: var(--bb-font-body);
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--bb-text);
  opacity: 0.9;
  white-space: nowrap;
}

.bb-header-state {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  order: 3;
  flex: 1 0 100%;
  justify-content: center;
  padding: 0.35rem 0.65rem;
  border: 1px solid var(--bb-grid);
  background: rgba(10, 31, 68, 0.5);
  min-width: 0;
}

.bb-state-dot {
  width: 0.45rem;
  height: 0.45rem;
  border-radius: 50%;
  background: var(--bb-neon);
  box-shadow: 0 0 8px var(--bb-neon);
  animation: bb-pulse 2.2s infinite;
  flex: 0 0 auto;
}

@keyframes bb-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.45; }
}

.bb-state-text {
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--bb-mut);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  text-transform: uppercase;
}

.bb-state-code {
  padding: 0.15rem 0.6rem 0.15rem 0.85rem;
  background: linear-gradient(90deg, var(--bb-card), var(--bb-card-float));
  color: var(--bb-gold);
  font-size: 0.68rem;
  letter-spacing: 0.15em;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 10% 100%);
  white-space: nowrap;
  flex: 0 0 auto;
}

.bb-header-actions {
  order: 2;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.bb-fav {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.45rem 0.7rem;
  background: transparent;
  border: 1px solid var(--bb-grid);
  color: var(--bb-mut);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s;
}

.bb-fav::before {
  content: "☆";
  color: var(--bb-gold);
  font-size: 0.9rem;
}

.bb-fav::after {
  content: attr(data-tooltip);
  position: absolute;
  right: 0;
  top: calc(100% + 0.45rem);
  z-index: 20;
  padding: 0.4rem 0.65rem;
  background: var(--bb-card-float);
  border: 1px solid var(--bb-gold);
  color: var(--bb-gold);
  font-size: 0.72rem;
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.bb-fav[data-tooltip]::after {
  opacity: 1;
  visibility: visible;
}

.bb-fav:hover {
  color: #fff;
  border-color: var(--bb-gold);
}

.bb-nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  background: transparent;
  border: 1px solid var(--bb-grid);
  color: var(--bb-text);
  cursor: pointer;
  transition: border-color 0.2s;
}

.bb-nav-toggle:hover {
  border-color: var(--bb-gold);
}

.bb-nav-toggle-line,
.bb-nav-toggle-line::before,
.bb-nav-toggle-line::after {
  content: "";
  display: block;
  width: 1.1rem;
  height: 2px;
  background: currentColor;
  transition: transform 0.22s, background 0.22s;
  position: relative;
}

.bb-nav-toggle-line::before {
  position: absolute;
  top: -0.38rem;
}

.bb-nav-toggle-line::after {
  position: absolute;
  top: 0.38rem;
}

.bb-nav-toggle[aria-expanded="true"] .bb-nav-toggle-line {
  background: transparent;
}

.bb-nav-toggle[aria-expanded="true"] .bb-nav-toggle-line::before {
  transform: rotate(45deg);
  top: 0;
}

.bb-nav-toggle[aria-expanded="true"] .bb-nav-toggle-line::after {
  transform: rotate(-45deg);
  top: 0;
}

.bb-header-navwrap {
  display: none;
  background: rgba(10, 31, 68, 0.96);
  border-top: 1px solid var(--bb-grid);
}

.bb-header-navwrap[data-open] {
  display: block;
}

.bb-nav {
  display: flex;
  flex-direction: column;
  padding-block: 0;
}

.bb-nav-link {
  display: block;
  padding: 0.8rem 0;
  color: var(--bb-mut);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9rem;
  letter-spacing: 0.06em;
  border-bottom: 1px solid rgba(30, 58, 109, 0.65);
  transition: color 0.18s, padding-left 0.18s;
}

.bb-nav-link:hover {
  color: #fff;
  padding-left: 0.35rem;
}

.bb-nav-link[aria-current="page"] {
  color: var(--bb-gold);
  border-left: 3px solid var(--bb-neon);
  padding-left: 0.75rem;
}

@media (min-width: 768px) {
  .bb-header-state {
    order: 2;
    flex: 0 0 auto;
    margin-left: auto;
  }

  .bb-header-actions {
    order: 3;
    margin-left: 0;
  }
}

@media (min-width: 992px) {
  .bb-header-navwrap {
    display: block;
  }

  .bb-nav {
    flex-direction: row;
    align-items: center;
    gap: 0;
  }

  .bb-nav-link {
    padding: 0.9rem 1.1rem 0.85rem;
    border-bottom: 2px solid transparent;
    margin-right: 0;
  }

  .bb-nav-link:hover,
  .bb-nav-link[aria-current="page"] {
    padding-left: 1.1rem;
    border-bottom-color: var(--bb-gold);
    color: var(--bb-gold);
    border-left: none;
  }

  .bb-nav-toggle {
    display: none;
  }
}

@media (max-width: 420px) {
  .bb-brand-en {
    font-size: 0.62rem;
    letter-spacing: 0.1em;
  }

  .bb-fav {
    font-size: 0.68rem;
    padding: 0.35rem 0.5rem;
  }
}

.bb-section {
  position: relative;
  padding-block: 2.5rem;
}

.bb-section-index {
  display: inline-block;
  margin-bottom: 0.6rem;
  padding: 0.2rem 0.65rem;
  background: linear-gradient(90deg, rgba(57, 255, 20, 0.08), rgba(212, 175, 55, 0.05));
  border-left: 3px solid var(--bb-neon);
  color: var(--bb-neon);
  font-family: var(--bb-font-display);
  letter-spacing: 0.16em;
  font-size: 0.72rem;
  text-transform: uppercase;
}

.bb-section-title {
  font-family: var(--bb-font-display);
  font-weight: 400;
  font-size: clamp(2rem, 5vw, 3.4rem);
  line-height: 1.02;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: #fff;
  margin-bottom: 0.7rem;
}

.bb-section-desc {
  color: var(--bb-mut);
  max-width: 52rem;
  font-size: 1rem;
}

.bb-prose {
  max-width: 68ch;
  color: #C9D4E8;
}

.bb-prose p {
  margin-bottom: 1rem;
}

.bb-prose h2,
.bb-prose h3 {
  font-family: var(--bb-font-display);
  color: #fff;
  letter-spacing: 0.03em;
  margin: 2rem 0 0.5rem;
  font-weight: 400;
}

.bb-prose h2 {
  font-size: 1.6rem;
}

.bb-prose ul,
.bb-prose ol {
  margin: 0 0 1rem 1.2rem;
}

.bb-prose ul {
  list-style: disc;
}

.bb-prose ol {
  list-style: decimal;
}

.bb-prose a {
  color: var(--bb-gold);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

.bb-grid {
  display: grid;
  gap: 1.25rem;
}

.bb-grid--2 {
  grid-template-columns: 1fr;
}

.bb-grid--3 {
  grid-template-columns: 1fr;
}

@media (min-width: 576px) {
  .bb-grid--2 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 768px) {
  .bb-grid--3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

.bb-btn {
  display: inline-block;
  padding: 0.72rem 1.3rem;
  border: 1px solid var(--bb-grid);
  background: transparent;
  color: var(--bb-mut);
  text-decoration: none;
  font-weight: 700;
  font-size: 0.86rem;
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: background 0.2s, color 0.2s, border-color 0.2s, transform 0.2s;
}

.bb-btn:hover {
  color: #fff;
  border-color: var(--bb-mut);
  transform: translateY(-1px);
}

.bb-btn-gold {
  background: var(--bb-gold);
  border-color: var(--bb-gold);
  color: var(--bb-navy);
}

.bb-btn-gold:hover {
  background: #e4c85e;
  border-color: #e4c85e;
  color: var(--bb-navy);
}

.bb-btn-neon {
  border-color: var(--bb-neon);
  color: var(--bb-neon);
}

.bb-btn-neon:hover {
  background: var(--bb-neon);
  color: var(--bb-navy);
}

.bb-card {
  position: relative;
  padding: 1.4rem 1.5rem;
  background: linear-gradient(180deg, rgba(13, 42, 77, 0.95), rgba(10, 31, 68, 0.85));
  border: 1px solid var(--bb-grid);
  border-left: 3px solid var(--bb-gold);
}

.bb-card-float {
  background: var(--bb-card-float);
  transform: translateY(-4px);
  box-shadow: 0 16px 30px rgba(0, 0, 0, 0.35);
}

.bb-card-metric {
  font-family: var(--bb-font-display);
  font-size: clamp(2.5rem, 6vw, 4rem);
  line-height: 1;
  color: var(--bb-neon);
  letter-spacing: 0.02em;
}

.bb-card-label {
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--bb-mut);
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}

.bb-tag {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  background: rgba(212, 175, 55, 0.08);
  color: var(--bb-gold);
  border: 1px solid rgba(212, 175, 55, 0.5);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  clip-path: polygon(0 0, 100% 0, 94% 100%, 0 100%);
}

.bb-image-placeholder {
  position: relative;
  aspect-ratio: 16 / 10;
  background: linear-gradient(145deg, var(--bb-card) 0%, var(--bb-card-float) 45%, #0A1F44 100%);
  border: 1px solid var(--bb-grid);
  overflow: hidden;
}

.bb-image-placeholder img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.bb-image-placeholder::before {
  content: attr(data-caption);
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 0.3rem 0.8rem;
  background: rgba(10, 31, 68, 0.88);
  color: var(--bb-mut);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  z-index: 2;
}

.bb-image-placeholder::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, transparent 42%, rgba(57, 255, 20, 0.08) 48%, transparent 58%),
    linear-gradient(45deg, transparent 50%, rgba(212, 175, 55, 0.12) 55%, transparent 64%);
  mix-blend-mode: screen;
}

.bb-image-placeholder--portrait {
  aspect-ratio: 4 / 5;
}

.bb-image-placeholder--wide {
  aspect-ratio: 21 / 9;
}

.bb-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem 0.75rem;
  padding: 0.75rem 0;
  font-size: 0.78rem;
  color: var(--bb-mut);
}

.bb-breadcrumb a {
  color: var(--bb-mut);
  text-decoration: none;
  transition: color 0.18s;
}

.bb-breadcrumb a:hover {
  color: #fff;
}

.bb-breadcrumb a[aria-current="page"] {
  color: var(--bb-gold);
}

.bb-breadcrumb-item {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.bb-breadcrumb-item + .bb-breadcrumb-item::before {
  content: "/";
  color: var(--bb-grid);
}

.bb-footer {
  position: relative;
  z-index: 2;
  margin-top: auto;
  background: linear-gradient(180deg, var(--bb-navy) 0%, #071C38 100%);
  border-top: 2px solid var(--bb-gold);
  overflow: hidden;
}

.bb-footer::before {
  content: "";
  position: absolute;
  top: -2px;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--bb-neon) 0%, var(--bb-gold) 55%, transparent 90%);
}

.bb-footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  padding-block: 2.5rem 2rem;
}

.bb-footer-brand .bb-brand {
  margin-right: 0;
  margin-bottom: 0.9rem;
}

.bb-footer-statement {
  color: var(--bb-mut);
  font-size: 0.85rem;
  max-width: 36rem;
  margin-bottom: 0.75rem;
}

.bb-footer-seal {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.25rem 0.7rem 0.25rem 0.95rem;
  background: linear-gradient(90deg, var(--bb-card), var(--bb-card-float));
  color: var(--bb-gold);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 8% 100%);
  text-transform: uppercase;
}

.bb-footer-seal::before {
  content: "●";
  color: var(--bb-neon);
  font-size: 0.5rem;
  border-radius: 50%;
  box-shadow: 0 0 6px var(--bb-neon);
}

.bb-footer-nav,
.bb-footer-meta {
  min-width: 0;
}

.bb-footer-title {
  font-family: var(--bb-font-display);
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #fff;
  font-size: 1rem;
  border-bottom: 1px solid var(--bb-grid);
  padding-bottom: 0.5rem;
  margin-bottom: 0.9rem;
}

.bb-footer-list li + li {
  margin-top: 0.45rem;
}

.bb-footer-list a {
  color: var(--bb-mut);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.18s, padding-left 0.18s;
}

.bb-footer-list a:hover {
  color: var(--bb-gold);
  padding-left: 0.25rem;
}

.bb-footer-meta p {
  color: var(--bb-mut);
  font-size: 0.85rem;
  line-height: 1.75;
  margin-bottom: 0.35rem;
}

.bb-footer-meta .bb-footer-list {
  margin-top: 0.8rem;
}

.bb-footer-note {
  margin-top: 0.65rem;
  padding: 0.55rem 0.7rem;
  border: 1px dashed var(--bb-grid);
  color: var(--bb-mut);
  font-size: 0.75rem;
}

.bb-footer-bottom {
  border-top: 1px solid var(--bb-grid);
  padding-block: 0.85rem;
}

.bb-footer-bottom-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.35rem 0.75rem;
  color: var(--bb-mut);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
}

@media (min-width: 768px) and (max-width: 991.98px) {
  .bb-footer-grid {
    grid-template-columns: 1fr 1fr;
  }

  .bb-footer-brand {
    grid-column: 1 / -1;
  }
}

@media (min-width: 992px) {
  .bb-footer-grid {
    grid-template-columns: 1.25fr 0.8fr 1.1fr;
  }

  .bb-footer-brand {
    grid-column: auto;
  }
}

.bb-to-top {
  position: fixed;
  right: 1.1rem;
  bottom: 1.1rem;
  z-index: 950;
  width: 2.6rem;
  height: 2.6rem;
  border: 1px solid var(--bb-gold);
  background: rgba(10, 31, 68, 0.92);
  color: var(--bb-gold);
  font-size: 1.05rem;
  line-height: 1;
  cursor: pointer;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 10% 100%);
  opacity: 0;
  visibility: hidden;
  transform: translateY(0.6rem);
  transition: opacity 0.2s, transform 0.2s, background 0.2s, color 0.2s;
}

.bb-to-top[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.bb-to-top:hover {
  background: var(--bb-gold);
  color: var(--bb-navy);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}