:root {
  --bg: #0b0b0d;
  --bg-elev: #141418;
  --bg-card: #1a1a20;
  --line: rgba(255, 255, 255, 0.08);
  --text: #f2f2f4;
  --muted: #9a9aa3;
  --accent: #3ddc84;
  --accent-2: #e53935;
  --accent-soft: rgba(61, 220, 132, 0.12);
  --radius: 14px;
  --max: 1120px;
  --font: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --display: "ZCOOL XiaoWei", "Noto Sans SC", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  background:
    radial-gradient(ellipse 80% 50% at 10% -10%, rgba(61, 220, 132, 0.08), transparent 50%),
    radial-gradient(ellipse 60% 40% at 90% 0%, rgba(229, 57, 53, 0.07), transparent 45%),
    linear-gradient(180deg, #0e0e12 0%, var(--bg) 40%, #080809 100%);
  color: var(--text);
  line-height: 1.75;
  min-height: 100vh;
}

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

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: #6ef0a8;
}

.container {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(11, 11, 13, 0.85);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.85rem 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--text);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  object-fit: cover;
}

.nav {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.nav a {
  color: var(--muted);
  padding: 0.45rem 0.75rem;
  border-radius: 999px;
  font-size: 0.95rem;
}

.nav a:hover,
.nav a.active {
  color: var(--text);
  background: var(--accent-soft);
}

.nav-toggle {
  display: none;
  background: var(--bg-card);
  border: 1px solid var(--line);
  color: var(--text);
  width: 42px;
  height: 42px;
  border-radius: 10px;
  cursor: pointer;
  font-size: 1.25rem;
}

/* Hero */
.hero {
  padding: 3.5rem 0 2.5rem;
  position: relative;
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 2.5rem;
  align-items: center;
}

.hero-brand {
  font-family: var(--display);
  font-size: clamp(2.6rem, 5vw, 3.8rem);
  line-height: 1.15;
  margin: 0 0 0.75rem;
  letter-spacing: 0.04em;
}

.hero-brand span {
  color: var(--accent-2);
}

.hero h1 {
  font-size: clamp(1.35rem, 2.4vw, 1.75rem);
  font-weight: 600;
  margin: 0 0 1rem;
  color: #e8e8ec;
  line-height: 1.45;
}

.hero-lead {
  color: var(--muted);
  font-size: 1.05rem;
  margin: 0 0 1.5rem;
  max-width: 36em;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.85rem 1.4rem;
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.98rem;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: linear-gradient(135deg, #3ddc84, #2bb86a);
  color: #06140c;
  box-shadow: 0 10px 28px rgba(61, 220, 132, 0.28);
}

.btn-primary:hover {
  color: #041008;
}

.btn-ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--text);
}

.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.5rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.hero-meta strong {
  color: var(--accent);
  font-weight: 600;
}

.hero-visual {
  position: relative;
}

.phone-frame {
  margin: 0 auto;
  width: min(100%, 320px);
  border-radius: 28px;
  padding: 10px;
  background: linear-gradient(160deg, #2a2a32, #121216);
  border: 1px solid var(--line);
  box-shadow:
    0 30px 60px rgba(0, 0, 0, 0.45),
    0 0 0 1px rgba(61, 220, 132, 0.08);
  animation: floatY 5s ease-in-out infinite;
}

.phone-frame img {
  border-radius: 20px;
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
}

@keyframes floatY {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

.badge-float {
  position: absolute;
  right: 0;
  bottom: 12%;
  background: var(--bg-elev);
  border: 1px solid var(--line);
  padding: 0.65rem 0.9rem;
  border-radius: 12px;
  font-size: 0.85rem;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
  animation: fadeInUp 0.8s ease 0.2s both;
}

.badge-float b {
  color: var(--accent);
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Sections */
.section {
  padding: 3.25rem 0;
}

.section-alt {
  background: rgba(255, 255, 255, 0.02);
  border-block: 1px solid var(--line);
}

.section-head {
  margin-bottom: 1.75rem;
  max-width: 46rem;
}

.section-head .eyebrow {
  display: inline-block;
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  margin-bottom: 0.5rem;
}

.section-head h2 {
  font-family: var(--display);
  font-size: clamp(1.6rem, 3vw, 2.15rem);
  margin: 0 0 0.65rem;
  line-height: 1.3;
}

.section-head p {
  margin: 0;
  color: var(--muted);
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.feature {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.35rem;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.feature:hover {
  border-color: rgba(61, 220, 132, 0.35);
  transform: translateY(-3px);
}

.feature h3 {
  margin: 0 0 0.55rem;
  font-size: 1.1rem;
}

.feature p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.shot {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--bg-card);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.shot:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.35);
}

.shot img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
}

.shot figcaption {
  padding: 0.75rem 0.9rem;
  font-size: 0.9rem;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

.shot figcaption strong {
  display: block;
  color: var(--text);
  margin-bottom: 0.2rem;
}

.content-block {
  background: var(--bg-elev);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.5rem 1.6rem;
  margin-bottom: 1.25rem;
}

.content-block h2,
.content-block h3 {
  margin-top: 0;
  font-family: var(--display);
}

.content-block p,
.content-block li {
  color: #c8c8d0;
}

.content-block ul,
.content-block ol {
  padding-left: 1.2rem;
}

.media-row {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 1.5rem;
  align-items: center;
  margin: 1.5rem 0;
}

.media-row.reverse {
  grid-template-columns: 1.1fr 0.9fr;
}

.media-row.reverse .media-copy {
  order: -1;
}

.media-pic {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
}

.media-pic img {
  width: 100%;
  aspect-ratio: 9 / 16;
  max-height: 520px;
  object-fit: cover;
  object-position: top;
  margin-inline: auto;
}

.steps {
  counter-reset: step;
  display: grid;
  gap: 1rem;
}

.step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1rem;
  align-items: start;
  padding: 1.1rem 1.2rem;
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.step::before {
  counter-increment: step;
  content: counter(step);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 700;
}

.step h3 {
  margin: 0 0 0.35rem;
  font-size: 1.05rem;
}

.step p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.faq details {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.9rem 1.1rem;
  margin-bottom: 0.7rem;
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq details[open] summary {
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.faq p {
  margin: 0;
  color: var(--muted);
}

.toc {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 1rem 0 1.5rem;
}

.toc a {
  background: var(--bg-card);
  border: 1px solid var(--line);
  color: var(--muted);
  padding: 0.4rem 0.75rem;
  border-radius: 999px;
  font-size: 0.88rem;
}

.toc a:hover {
  color: var(--accent);
  border-color: rgba(61, 220, 132, 0.4);
}

.legal-page .content-block h2 {
  font-size: 1.35rem;
}

.page-hero {
  padding: 2.5rem 0 1rem;
}

.page-hero h1 {
  font-family: var(--display);
  font-size: clamp(1.8rem, 3.5vw, 2.4rem);
  margin: 0 0 0.6rem;
}

.page-hero p {
  margin: 0;
  color: var(--muted);
  max-width: 40rem;
}

.breadcrumb {
  font-size: 0.88rem;
  color: var(--muted);
  margin-bottom: 0.85rem;
}

.breadcrumb a {
  color: var(--muted);
}

.breadcrumb a:hover {
  color: var(--accent);
}

/* Error pages */
.error-wrap {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 3rem 1rem;
}

.error-wrap h1 {
  font-family: var(--display);
  font-size: clamp(3rem, 10vw, 5rem);
  margin: 0 0 0.5rem;
  color: var(--accent-2);
}

.error-wrap p {
  color: var(--muted);
  margin: 0 0 1.5rem;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--line);
  background: #08080a;
  padding: 2.5rem 0 1.5rem;
  margin-top: 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-brand {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
}

.footer-brand img {
  width: 48px;
  height: 48px;
  border-radius: 10px;
}

.footer-brand p {
  margin: 0.35rem 0 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.footer-col h4 {
  margin: 0 0 0.75rem;
  font-size: 0.95rem;
}

.footer-col a {
  display: block;
  color: var(--muted);
  margin-bottom: 0.45rem;
  font-size: 0.92rem;
}

.footer-col a:hover {
  color: var(--accent);
}

.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 1rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem;
  color: var(--muted);
  font-size: 0.85rem;
}

.age-note {
  background: rgba(229, 57, 53, 0.1);
  border: 1px solid rgba(229, 57, 53, 0.35);
  color: #ffb4b0;
  padding: 0.85rem 1rem;
  border-radius: 12px;
  font-size: 0.9rem;
  margin: 1rem 0 0;
}

.related-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1rem;
}

.related-links a {
  border: 1px solid var(--line);
  background: var(--bg-card);
  color: var(--text);
  padding: 0.45rem 0.8rem;
  border-radius: 10px;
  font-size: 0.88rem;
}

.related-links a:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* Motion */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Mobile */
@media (max-width: 900px) {
  .nav-toggle {
    display: grid;
    place-items: center;
  }

  .nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(14, 14, 18, 0.98);
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    align-items: stretch;
    padding: 0.75rem;
    display: none;
  }

  .nav.open {
    display: flex;
  }

  .nav a {
    padding: 0.75rem 1rem;
  }

  .hero-grid,
  .grid-2,
  .grid-3,
  .grid-4,
  .media-row,
  .media-row.reverse,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .media-row.reverse .media-copy {
    order: 0;
  }

  .hero {
    padding-top: 2rem;
  }

  .phone-frame {
    width: min(100%, 280px);
  }

  .badge-float {
    display: none;
  }

  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 560px) {
  .grid-3 {
    grid-template-columns: 1fr;
  }

  .cta-row {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }
}

/* Sticky promo ads bar (below header) */
#site-ads {
  position: sticky;
  top: 64px;
  z-index: 90;
}
@media (max-width: 900px) {
  #site-ads { top: 58px; }
}