:root {
  --bkhl-navy: #0c1222;
  --bkhl-ink: #151d2e;
  --bkhl-teal: #14b8a6;
  --bkhl-teal-dim: #0d9488;
  --bkhl-amber: #f59e0b;
  --bkhl-coral: #fb7185;
  --bkhl-sky: #e0f2fe;
  --bkhl-mist: #f8fafc;
  --bkhl-paper: #fffdf9;
  --bkhl-text: #1e293b;
  --bkhl-muted: #64748b;
  --bkhl-line: rgba(20, 184, 166, 0.22);
  --bkhl-glass: rgba(255, 255, 255, 0.78);
  --bkhl-nav-h: 60px;
  --bkhl-dl-h: 0px;
  --bkhl-radius: 18px;
  --bkhl-shadow: 0 14px 40px rgba(12, 18, 34, 0.09);
  font-size: 16px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bkhl-paper);
  color: var(--bkhl-text);
  line-height: 1.82;
  min-height: 100vh;
  overflow-x: hidden;
}

body.bkhl-dl-active { padding-top: var(--bkhl-dl-h); }

body::after {
  content: "";
  position: fixed;
  inset: 0;
  background:
    radial-gradient(ellipse 70% 50% at 0% 0%, rgba(20, 184, 166, 0.07), transparent 55%),
    radial-gradient(ellipse 60% 45% at 100% 20%, rgba(251, 113, 133, 0.06), transparent 50%),
    radial-gradient(ellipse 50% 40% at 50% 100%, rgba(245, 158, 11, 0.05), transparent 45%);
  pointer-events: none;
  z-index: 0;
}

a { color: var(--bkhl-teal-dim); text-decoration: none; transition: color 0.2s ease; }
a:hover { color: var(--bkhl-coral); }

img { max-width: 100%; height: auto; display: block; }

.bkhl-wrap {
  width: min(1140px, 93vw);
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

/* Navigation */
.bkhl-navband {
  position: sticky;
  top: 0;
  z-index: 1100;
  background: var(--bkhl-glass);
  backdrop-filter: blur(16px) saturate(1.4);
  border-bottom: 1px solid var(--bkhl-line);
  height: var(--bkhl-nav-h);
}

.bkhl-nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--bkhl-nav-h);
  gap: 14px;
}

.bkhl-mark {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--bkhl-navy);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.02em;
}

.bkhl-mark img {
  width: 38px;
  height: 38px;
  border-radius: 11px;
  box-shadow: 0 4px 14px rgba(20, 184, 166, 0.25);
}

.bkhl-menu-list {
  display: flex;
  list-style: none;
  gap: 6px;
}

.bkhl-menu-list a {
  display: block;
  padding: 8px 14px;
  border-radius: 999px;
  color: var(--bkhl-muted);
  font-size: 0.92rem;
  font-weight: 500;
  transition: background 0.2s, color 0.2s;
}

.bkhl-menu-list a:hover,
.bkhl-menu-list a.bkhl-on {
  background: rgba(20, 184, 166, 0.12);
  color: var(--bkhl-teal-dim);
}

.bkhl-burger {
  display: none;
  background: none;
  border: none;
  font-size: 1.4rem;
  color: var(--bkhl-navy);
  cursor: pointer;
  padding: 6px;
}

/* Sticky download strip */
.bkhl-floatdl {
  position: fixed;
  top: var(--bkhl-nav-h);
  left: 0;
  right: 0;
  z-index: 1050;
  background: linear-gradient(90deg, var(--bkhl-ink), #1a2744);
  border-bottom: 1px solid rgba(20, 184, 166, 0.35);
  transform: translateY(-110%);
  opacity: 0;
  transition: transform 0.32s ease, opacity 0.32s ease;
  pointer-events: none;
}

.bkhl-floatdl.bkhl-show {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.bkhl-floatdl-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px 14px;
  padding: 10px 12px;
  max-width: 1140px;
  margin: 0 auto;
}

.bkhl-dl-chip {
  width: calc(12.5% - 13px);
  min-width: 72px;
  text-align: center;
}

.bkhl-dl-chip a {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  color: #e2e8f0;
  font-size: 0.68rem;
}

.bkhl-dl-chip img {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  object-fit: cover;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
  transition: transform 0.18s ease;
}

.bkhl-dl-chip a:hover img { transform: scale(1.06); }
.bkhl-dl-chip span {
  max-width: 72px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* Ads top section */
.bkhl-promo-top {
  padding: 14px 0 6px;
}

#ads {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px;
  background: transparent;
}

#ads > div {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 70px;
}

#ads img {
  width: 65px;
  height: 65px;
  object-fit: cover;
  border-radius: 16px;
  box-shadow: var(--bkhl-shadow);
  transition: transform 0.18s ease;
}

#ads img:hover { transform: translateY(-3px); }

#ads .caption {
  font-size: 11px;
  color: var(--bkhl-muted);
  text-align: center;
  max-width: 68px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  margin-top: 4px;
}

/* Hero spotlight */
.bkhl-spotlight {
  padding: 36px 0 48px;
  position: relative;
}

.bkhl-spotlight::before {
  content: "";
  position: absolute;
  top: -20px;
  right: -8%;
  width: 55%;
  height: 120%;
  background: linear-gradient(135deg, rgba(20, 184, 166, 0.08), rgba(251, 113, 133, 0.06));
  clip-path: polygon(18% 0, 100% 0, 100% 100%, 0 100%);
  border-radius: 0 0 0 80px;
  z-index: -1;
}

.bkhl-eyebrow {
  display: inline-block;
  padding: 5px 14px;
  background: linear-gradient(135deg, var(--bkhl-teal), var(--bkhl-teal-dim));
  color: #fff;
  font-size: 0.78rem;
  font-weight: 600;
  border-radius: 999px;
  letter-spacing: 0.06em;
  margin-bottom: 18px;
}

.bkhl-spotlight h1 {
  font-size: clamp(1.55rem, 4.8vw, 2.35rem);
  line-height: 1.35;
  color: var(--bkhl-navy);
  font-weight: 800;
  margin-bottom: 20px;
  max-width: 820px;
}

.bkhl-lead {
  font-size: 1.02rem;
  color: var(--bkhl-muted);
  max-width: 780px;
  margin-bottom: 0;
}

/* Content blocks */
.bkhl-block {
  padding: 52px 0;
  border-top: 1px solid rgba(20, 184, 166, 0.1);
}

.bkhl-block:first-of-type { border-top: none; }

.bkhl-block-head {
  margin-bottom: 32px;
}

.bkhl-block-head h2 {
  font-size: clamp(1.3rem, 3.5vw, 1.75rem);
  color: var(--bkhl-navy);
  font-weight: 700;
  margin-bottom: 10px;
}

.bkhl-block-head p {
  color: var(--bkhl-muted);
  font-size: 0.98rem;
}

.bkhl-prose h3 {
  font-size: 1.15rem;
  color: var(--bkhl-ink);
  margin: 28px 0 12px;
  font-weight: 650;
}

.bkhl-prose h3:first-child { margin-top: 0; }

.bkhl-prose p {
  margin-bottom: 16px;
  text-align: justify;
}

.bkhl-prose ul {
  margin: 12px 0 18px 22px;
}

.bkhl-prose li { margin-bottom: 8px; }

/* Split layout */
.bkhl-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  align-items: center;
}

.bkhl-split.bkhl-flip .bkhl-shot { order: 2; }

.bkhl-shot {
  border-radius: var(--bkhl-radius);
  overflow: hidden;
  box-shadow: var(--bkhl-shadow);
  border: 1px solid var(--bkhl-line);
  background: #fff;
}

.bkhl-shot img { width: 100%; }

.bkhl-shot figcaption {
  padding: 10px 14px;
  font-size: 0.82rem;
  color: var(--bkhl-muted);
  background: var(--bkhl-mist);
  text-align: center;
}

/* Mosaic cards */
.bkhl-mosaic {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin: 28px 0;
}

.bkhl-tile {
  background: #fff;
  border: 1px solid var(--bkhl-line);
  border-radius: var(--bkhl-radius);
  padding: 22px 20px;
  box-shadow: 0 6px 20px rgba(12, 18, 34, 0.04);
  transition: transform 0.22s ease, box-shadow 0.22s ease;
}

.bkhl-tile:hover {
  transform: translateY(-4px);
  box-shadow: var(--bkhl-shadow);
}

.bkhl-tile-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  margin-bottom: 14px;
  background: linear-gradient(135deg, rgba(20, 184, 166, 0.15), rgba(245, 158, 11, 0.12));
}

.bkhl-tile h3 {
  font-size: 1.02rem;
  color: var(--bkhl-navy);
  margin-bottom: 8px;
}

.bkhl-tile p {
  font-size: 0.9rem;
  color: var(--bkhl-muted);
  line-height: 1.7;
}

/* Ribbon stats */
.bkhl-ribbon {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  margin: 32px 0;
}

.bkhl-stat {
  text-align: center;
  padding: 20px 12px;
  background: linear-gradient(160deg, var(--bkhl-sky), #fff);
  border-radius: 14px;
  border: 1px solid var(--bkhl-line);
}

.bkhl-stat strong {
  display: block;
  font-size: 1.4rem;
  color: var(--bkhl-teal-dim);
  margin-bottom: 4px;
}

.bkhl-stat span {
  font-size: 0.82rem;
  color: var(--bkhl-muted);
}

/* Tags */
.bkhl-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 20px;
}

.bkhl-tag {
  padding: 5px 12px;
  background: rgba(20, 184, 166, 0.1);
  color: var(--bkhl-teal-dim);
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 500;
}

/* Combo: cards + image */
.bkhl-combo {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 28px;
  align-items: start;
}

.bkhl-combo-cards {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

/* Breadcrumb */
.bkhl-crumb {
  padding: 16px 0 0;
  font-size: 0.85rem;
  color: var(--bkhl-muted);
}

.bkhl-crumb a { color: var(--bkhl-teal-dim); }
.bkhl-crumb span { margin: 0 6px; }

/* Legal pages */
.bkhl-legal {
  padding: 28px 0 60px;
}

.bkhl-legal h1 {
  font-size: 1.65rem;
  color: var(--bkhl-navy);
  margin-bottom: 8px;
}

.bkhl-legal .bkhl-updated {
  font-size: 0.85rem;
  color: var(--bkhl-muted);
  margin-bottom: 28px;
}

.bkhl-legal h2 {
  font-size: 1.2rem;
  color: var(--bkhl-ink);
  margin: 32px 0 12px;
  padding-left: 12px;
  border-left: 3px solid var(--bkhl-teal);
}

.bkhl-legal p, .bkhl-legal li {
  margin-bottom: 12px;
  text-align: justify;
}

.bkhl-legal ul, .bkhl-legal ol {
  margin: 10px 0 16px 24px;
}

/* Error pages */
.bkhl-error {
  text-align: center;
  padding: 48px 0 72px;
}

.bkhl-error-code {
  font-size: 5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--bkhl-teal), var(--bkhl-coral));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 16px;
}

.bkhl-error h1 {
  font-size: 1.4rem;
  color: var(--bkhl-navy);
  margin-bottom: 12px;
}

.bkhl-error p {
  color: var(--bkhl-muted);
  margin-bottom: 24px;
}

.bkhl-btn {
  display: inline-block;
  padding: 12px 28px;
  background: linear-gradient(135deg, var(--bkhl-teal), var(--bkhl-teal-dim));
  color: #fff !important;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  box-shadow: 0 6px 20px rgba(20, 184, 166, 0.3);
  transition: transform 0.2s, box-shadow 0.2s;
}

.bkhl-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 28px rgba(20, 184, 166, 0.38);
  color: #fff !important;
}

.bkhl-btn-ghost {
  background: transparent;
  border: 2px solid var(--bkhl-teal);
  color: var(--bkhl-teal-dim) !important;
  box-shadow: none;
}

.bkhl-btn-ghost:hover {
  background: rgba(20, 184, 166, 0.08);
  color: var(--bkhl-teal-dim) !important;
}

/* Footer */
.bkhl-foot {
  background: var(--bkhl-navy);
  color: #94a3b8;
  padding: 40px 0 28px;
  margin-top: 20px;
}

.bkhl-foot-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 28px;
}

.bkhl-foot h3 {
  color: #e2e8f0;
  font-size: 0.95rem;
  margin-bottom: 14px;
}

.bkhl-foot ul { list-style: none; }

.bkhl-foot li { margin-bottom: 8px; }

.bkhl-foot a { color: #94a3b8; }
.bkhl-foot a:hover { color: var(--bkhl-teal); }

.bkhl-foot-copy {
  text-align: center;
  font-size: 0.8rem;
  padding-top: 20px;
  border-top: 1px solid rgba(148, 163, 184, 0.2);
}

/* Responsive */
@media (max-width: 900px) {
  .bkhl-split,
  .bkhl-combo { grid-template-columns: 1fr; }
  .bkhl-split.bkhl-flip .bkhl-shot { order: 0; }
  .bkhl-mosaic { grid-template-columns: 1fr 1fr; }
  .bkhl-ribbon { grid-template-columns: 1fr 1fr; }
  .bkhl-foot-grid { grid-template-columns: 1fr; }
  .bkhl-dl-chip { width: calc(25% - 11px); }
}

@media (max-width: 640px) {
  .bkhl-burger { display: block; }
  .bkhl-menu-list {
    display: none;
    position: absolute;
    top: var(--bkhl-nav-h);
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--bkhl-glass);
    backdrop-filter: blur(16px);
    padding: 12px 16px 18px;
    border-bottom: 1px solid var(--bkhl-line);
    box-shadow: var(--bkhl-shadow);
  }
  .bkhl-menu-list.bkhl-open { display: flex; }
  .bkhl-mosaic { grid-template-columns: 1fr; }
  .bkhl-ribbon { grid-template-columns: 1fr 1fr; }
  .bkhl-dl-chip { width: calc(25% - 11px); }
  .bkhl-spotlight { padding: 24px 0 32px; }
  .bkhl-block { padding: 36px 0; }
}

@media (min-width: 901px) {
  .bkhl-dl-chip { width: calc(12.5% - 13px); }
}