@import url("https://fonts.googleapis.com/css2?family=ZCOOL+QingKe+HuangYou&family=Noto+Sans+SC:wght@400;500;700;900&display=swap");

:root {
  --bch-ink: #0e1621;
  --bch-ink-soft: #1c2a3a;
  --bch-coral: #ff5c7a;
  --bch-coral-deep: #e03d5c;
  --bch-mint: #2dd4bf;
  --bch-mint-deep: #14b8a6;
  --bch-mist: #e7eef6;
  --bch-paper: #f7fafc;
  --bch-line: rgba(14, 22, 33, 0.08);
  --bch-glass: rgba(255, 255, 255, 0.68);
  --bch-shadow: 0 18px 48px rgba(14, 22, 33, 0.12);
  --bch-radius: 22px;
  --bch-nav-h: 64px;
  --bch-promo-gap: 12px;
  --bch-max: 1080px;
  --bch-font-display: "ZCOOL QingKe HuangYou", "Noto Sans SC", sans-serif;
  --bch-font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--bch-font-body);
  color: var(--bch-ink);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(255, 92, 122, 0.18), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(45, 212, 191, 0.16), transparent 50%),
    linear-gradient(180deg, #f4f8fc 0%, var(--bch-mist) 42%, #eef3f8 100%);
  line-height: 1.75;
  min-height: 100vh;
  overflow-x: hidden;
}

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

a {
  color: var(--bch-coral-deep);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--bch-ink);
}

.bch-skip {
  position: absolute;
  left: -9999px;
}

.bch-wrap {
  width: min(100% - 32px, var(--bch-max));
  margin-inline: auto;
}

/* Top promo strip */
.bch-promo {
  background: linear-gradient(90deg, rgba(14, 22, 33, 0.92), rgba(28, 42, 58, 0.95));
  padding: 10px 0 6px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.bch-promo-inner {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 8px 10px;
}

.bch-promo-item {
  width: 68px;
  text-align: center;
}

.bch-promo-item a {
  display: inline-block;
  border-radius: 16px;
  text-decoration: none;
}

.bch-promo-item img {
  width: 58px;
  height: 58px;
  object-fit: cover;
  border-radius: 16px;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.28);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.bch-promo-item img:hover {
  transform: translateY(-3px) scale(1.05);
}

.bch-promo-item span {
  display: block;
  margin-top: 4px;
  font-size: 11px;
  color: rgba(255, 255, 255, 0.72);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* Navigation */
.bch-nav {
  position: sticky;
  top: 0;
  z-index: 80;
  height: var(--bch-nav-h);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(247, 250, 252, 0.82);
  border-bottom: 1px solid var(--bch-line);
}

.bch-nav-bar {
  height: var(--bch-nav-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.bch-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--bch-ink);
}

.bch-brand img {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  object-fit: cover;
  box-shadow: 0 6px 16px rgba(255, 92, 122, 0.28);
}

.bch-brand strong {
  font-family: var(--bch-font-display);
  font-size: 1.35rem;
  letter-spacing: 0.04em;
  font-weight: 400;
}

.bch-menu-btn {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--bch-line);
  border-radius: 12px;
  background: var(--bch-glass);
  cursor: pointer;
}

.bch-menu-btn span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: var(--bch-ink);
  border-radius: 2px;
}

.bch-links {
  display: flex;
  align-items: center;
  gap: 6px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.bch-links a {
  display: inline-flex;
  padding: 8px 14px;
  border-radius: 999px;
  text-decoration: none;
  color: var(--bch-ink-soft);
  font-size: 0.92rem;
  font-weight: 500;
  transition: background 0.2s ease, color 0.2s ease;
}

.bch-links a:hover,
.bch-links a.is-on {
  background: rgba(255, 92, 122, 0.12);
  color: var(--bch-coral-deep);
}

/* Fixed download dock after scroll */
.bch-dock {
  position: sticky;
  top: var(--bch-nav-h);
  z-index: 70;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  pointer-events: none;
  background: rgba(14, 22, 33, 0.94);
  backdrop-filter: blur(12px);
  transition: max-height 0.28s ease, opacity 0.28s ease, padding 0.28s ease;
}

.bch-dock.is-show {
  max-height: 220px;
  opacity: 1;
  pointer-events: auto;
  padding: 8px 0 10px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.bch-dock-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px 6px;
  justify-items: center;
}

.bch-dock-item {
  width: 100%;
  max-width: 72px;
  text-align: center;
}

.bch-dock-item a {
  text-decoration: none;
  display: inline-block;
}

.bch-dock-item img {
  width: 48px;
  height: 48px;
  border-radius: 14px;
  object-fit: cover;
  margin-inline: auto;
  box-shadow: 0 6px 14px rgba(0, 0, 0, 0.25);
}

.bch-dock-item span {
  display: block;
  margin-top: 3px;
  font-size: 10px;
  color: rgba(255, 255, 255, 0.7);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* Hero */
.bch-hero {
  position: relative;
  isolation: isolate;
  min-height: min(92vh, 820px);
  display: grid;
  align-items: end;
  overflow: hidden;
  color: #fff;
}

.bch-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(120deg, rgba(14, 22, 33, 0.82) 8%, rgba(14, 22, 33, 0.35) 48%, rgba(14, 22, 33, 0.55) 100%),
    url("shot-comic-serial.jpg") center / cover no-repeat;
  z-index: -2;
  transform: scale(1.04);
  animation: bch-drift 18s ease-in-out infinite alternate;
}

.bch-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 28%;
  background: linear-gradient(180deg, transparent, var(--bch-mist));
  z-index: -1;
}

.bch-hero-panel {
  padding: 72px 0 56px;
}

.bch-kicker {
  display: inline-block;
  font-size: 0.82rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--bch-mint);
  margin-bottom: 14px;
}

.bch-hero h1 {
  margin: 0 0 16px;
  font-family: var(--bch-font-display);
  font-size: clamp(2rem, 6vw, 3.4rem);
  line-height: 1.25;
  font-weight: 400;
  max-width: 14em;
  text-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
}

.bch-hero-lead {
  margin: 0;
  max-width: 34em;
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.88);
}

.bch-orbit {
  position: absolute;
  width: 220px;
  height: 220px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 50%;
  right: 8%;
  top: 18%;
  animation: bch-spin 24s linear infinite;
  pointer-events: none;
}

.bch-orbit::before {
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--bch-coral);
  top: -7px;
  left: 50%;
  box-shadow: 0 0 18px var(--bch-coral);
}

/* Sections */
.bch-section {
  padding: 56px 0;
}

.bch-section h2 {
  margin: 0 0 12px;
  font-family: var(--bch-font-display);
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  font-weight: 400;
  line-height: 1.3;
}

.bch-section h3 {
  margin: 28px 0 10px;
  font-size: 1.2rem;
  color: var(--bch-ink-soft);
}

.bch-lead {
  margin: 0 0 24px;
  color: #445466;
  max-width: 46em;
}

.bch-prose p {
  margin: 0 0 1em;
  font-size: 1.02rem;
  color: #243447;
}

.bch-prose strong {
  color: var(--bch-ink);
  font-weight: 700;
}

/* Zigzag media */
.bch-zig {
  display: grid;
  gap: 28px;
  align-items: center;
  margin: 36px 0;
}

.bch-phone {
  position: relative;
  margin-inline: auto;
  width: min(100%, 280px);
  border-radius: 28px;
  overflow: hidden;
  box-shadow: var(--bch-shadow);
  border: 3px solid rgba(255, 255, 255, 0.9);
  background: #111;
  transform: rotate(-2deg);
  transition: transform 0.35s ease;
}

.bch-phone:hover {
  transform: rotate(0deg) translateY(-6px);
}

.bch-phone img {
  width: 100%;
  aspect-ratio: 9 / 19;
  object-fit: cover;
  object-position: top;
}

.bch-phone.is-tilt {
  transform: rotate(2.5deg);
}

.bch-phone.is-tilt:hover {
  transform: rotate(0deg) translateY(-6px);
}

.bch-chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 18px 0 8px;
}

.bch-chip {
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(45, 212, 191, 0.14);
  color: #0f766e;
  font-size: 0.82rem;
  font-weight: 500;
}

/* Feature mosaic */
.bch-mosaic {
  display: grid;
  gap: 14px;
  margin-top: 28px;
}

.bch-tile {
  position: relative;
  overflow: hidden;
  border-radius: var(--bch-radius);
  background: var(--bch-glass);
  border: 1px solid rgba(255, 255, 255, 0.7);
  box-shadow: 0 10px 30px rgba(14, 22, 33, 0.06);
  padding: 22px;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

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

.bch-tile h3 {
  margin-top: 0;
}

.bch-tile p {
  margin: 0;
  color: #445466;
  font-size: 0.95rem;
}

.bch-tile-num {
  position: absolute;
  right: 14px;
  top: 8px;
  font-family: var(--bch-font-display);
  font-size: 2.4rem;
  color: rgba(255, 92, 122, 0.18);
  line-height: 1;
}

/* Split band */
.bch-band {
  margin: 40px 0;
  padding: 28px;
  border-radius: 28px;
  background:
    linear-gradient(135deg, rgba(255, 92, 122, 0.12), rgba(45, 212, 191, 0.1)),
    var(--bch-paper);
  border: 1px solid rgba(255, 255, 255, 0.8);
}

.bch-band-grid {
  display: grid;
  gap: 20px;
  align-items: center;
}

.bch-shot {
  border-radius: 18px;
  overflow: hidden;
  box-shadow: var(--bch-shadow);
}

.bch-shot img {
  width: 100%;
  aspect-ratio: 16 / 11;
  object-fit: cover;
  object-position: top;
}

/* Timeline */
.bch-timeline {
  position: relative;
  margin: 32px 0;
  padding-left: 22px;
}

.bch-timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(180deg, var(--bch-coral), var(--bch-mint));
}

.bch-node {
  position: relative;
  margin-bottom: 22px;
  padding: 16px 18px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--bch-line);
}

.bch-node::before {
  content: "";
  position: absolute;
  left: -22px;
  top: 22px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--bch-coral);
  box-shadow: 0 0 0 4px rgba(255, 92, 122, 0.18);
}

.bch-node h3 {
  margin: 0 0 6px;
}

.bch-node p {
  margin: 0;
  color: #445466;
}

/* CTA strip (body only, not hero/nav) */
.bch-cta {
  margin: 40px 0;
  padding: 28px;
  border-radius: 24px;
  background: linear-gradient(120deg, var(--bch-ink), #243447);
  color: #fff;
  display: grid;
  gap: 16px;
  align-items: center;
}

.bch-cta p {
  margin: 0;
  color: rgba(255, 255, 255, 0.86);
}

.bch-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 46px;
  padding: 0 22px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--bch-coral), #ff7a55);
  color: #fff !important;
  text-decoration: none !important;
  font-weight: 700;
  box-shadow: 0 12px 28px rgba(255, 92, 122, 0.35);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  width: fit-content;
}

.bch-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 32px rgba(255, 92, 122, 0.42);
}

/* Breadcrumb */
.bch-crumb {
  padding: 18px 0 0;
  font-size: 0.88rem;
  color: #607285;
}

.bch-crumb a {
  color: #607285;
  text-decoration: none;
}

.bch-crumb a:hover {
  color: var(--bch-coral-deep);
}

.bch-crumb span {
  margin: 0 6px;
  opacity: 0.5;
}

/* Legal / sub pages */
.bch-page-head {
  padding: 28px 0 8px;
}

.bch-page-head h1 {
  margin: 8px 0 12px;
  font-family: var(--bch-font-display);
  font-size: clamp(1.8rem, 5vw, 2.6rem);
  font-weight: 400;
}

.bch-legal {
  padding-bottom: 64px;
}

.bch-legal h2 {
  margin-top: 36px;
  font-size: 1.35rem;
}

.bch-legal p,
.bch-legal li {
  color: #243447;
}

.bch-legal ul {
  padding-left: 1.2em;
}

/* Error pages */
.bch-error {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 48px 0;
}

.bch-error-code {
  font-family: var(--bch-font-display);
  font-size: clamp(4rem, 16vw, 7rem);
  line-height: 1;
  background: linear-gradient(135deg, var(--bch-coral), var(--bch-mint));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin: 0;
}

.bch-error h1 {
  font-family: var(--bch-font-display);
  font-weight: 400;
  margin: 8px 0 12px;
}

/* Footer */
.bch-foot {
  margin-top: 40px;
  padding: 36px 0 48px;
  background: var(--bch-ink);
  color: rgba(255, 255, 255, 0.78);
}

.bch-foot a {
  color: rgba(255, 255, 255, 0.88);
  text-decoration: none;
}

.bch-foot a:hover {
  color: var(--bch-mint);
}

.bch-foot-grid {
  display: grid;
  gap: 24px;
}

.bch-foot h3 {
  margin: 0 0 10px;
  font-family: var(--bch-font-display);
  font-weight: 400;
  color: #fff;
  font-size: 1.2rem;
}

.bch-foot ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

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

.bch-copy {
  margin-top: 28px;
  padding-top: 18px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.86rem;
  color: rgba(255, 255, 255, 0.5);
}

/* Reveal motion */
.bch-reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.bch-reveal.is-in {
  opacity: 1;
  transform: none;
}

@keyframes bch-drift {
  from {
    transform: scale(1.04) translate3d(0, 0, 0);
  }
  to {
    transform: scale(1.1) translate3d(-1.5%, -1%, 0);
  }
}

@keyframes bch-spin {
  to {
    transform: rotate(360deg);
  }
}

@media (min-width: 720px) {
  .bch-dock-grid {
    grid-template-columns: repeat(8, minmax(0, 1fr));
  }

  .bch-zig {
    grid-template-columns: 0.9fr 1.1fr;
  }

  .bch-zig.is-flip {
    grid-template-columns: 1.1fr 0.9fr;
  }

  .bch-zig.is-flip .bch-phone {
    order: 2;
  }

  .bch-mosaic {
    grid-template-columns: repeat(2, 1fr);
  }

  .bch-band-grid {
    grid-template-columns: 1.1fr 0.9fr;
  }

  .bch-band-grid.is-flip {
    grid-template-columns: 0.9fr 1.1fr;
  }

  .bch-band-grid.is-flip .bch-shot {
    order: -1;
  }

  .bch-cta {
    grid-template-columns: 1fr auto;
  }

  .bch-foot-grid {
    grid-template-columns: 1.4fr 1fr 1fr;
  }
}

@media (min-width: 960px) {
  .bch-mosaic {
    grid-template-columns: repeat(3, 1fr);
  }

  .bch-mosaic .bch-tile:nth-child(1) {
    grid-column: span 2;
  }
}

@media (max-width: 860px) {
  .bch-menu-btn {
    display: inline-grid;
    place-items: center;
  }

  .bch-links {
    position: absolute;
    left: 16px;
    right: 16px;
    top: calc(var(--bch-nav-h) + 8px);
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: 10px;
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.96);
    box-shadow: var(--bch-shadow);
    border: 1px solid var(--bch-line);
  }

  .bch-links.is-open {
    display: flex;
  }

  .bch-links a {
    border-radius: 12px;
  }
}