:root {
  --bg: #0a0a0c;
  --bg-soft: #121218;
  --bg-card: #1a1a22;
  --text: #f2f2f5;
  --text-muted: #a8a8b3;
  --pink: #ff2d6a;
  --pink-deep: #e01e55;
  --coral: #ff7a45;
  --grad: linear-gradient(135deg, #ff2d6a 0%, #ff7a45 100%);
  --border: rgba(255, 45, 106, 0.22);
  --radius: 14px;
  --shadow: 0 12px 40px rgba(0, 0, 0, 0.45);
  --max: 1120px;
  --font: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  min-height: 100vh;
}

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

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

a:hover {
  color: var(--coral);
}

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

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 10, 12, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

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

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
  padding: 8px 12px;
  border-radius: 8px;
  cursor: pointer;
}

.nav-menu {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-menu a {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.nav-menu a:hover,
.nav-menu a.active {
  color: var(--pink);
}

/* Hero */
.hero {
  position: relative;
  overflow: hidden;
  padding: 56px 0 48px;
  background:
    radial-gradient(ellipse 80% 60% at 70% 20%, rgba(255, 45, 106, 0.18), transparent 55%),
    radial-gradient(ellipse 50% 40% at 10% 80%, rgba(255, 122, 69, 0.12), transparent 50%),
    var(--bg);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: center;
}

.hero-badge {
  display: inline-block;
  padding: 4px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--coral);
  font-size: 0.82rem;
  margin-bottom: 14px;
}

.hero h1 {
  margin: 0 0 16px;
  font-size: clamp(1.7rem, 3.5vw, 2.55rem);
  line-height: 1.25;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-lead {
  color: var(--text-muted);
  font-size: 1.05rem;
  margin: 0 0 28px;
  max-width: 36em;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, opacity 0.2s ease;
}

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

.btn-primary {
  background: var(--grad);
  color: #fff;
  box-shadow: 0 8px 24px rgba(255, 45, 106, 0.35);
}

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

.btn-ghost {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
}

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

.hero-visual {
  position: relative;
}

.hero-visual img {
  width: 100%;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.hero-float {
  position: absolute;
  right: -8px;
  bottom: -12px;
  width: 42%;
  border-radius: 12px;
  border: 2px solid rgba(255, 45, 106, 0.4);
  box-shadow: var(--shadow);
}

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

.section-alt {
  background: var(--bg-soft);
}

.section-head {
  margin-bottom: 32px;
  max-width: 48em;
}

.section-head h2 {
  margin: 0 0 10px;
  font-size: clamp(1.35rem, 2.4vw, 1.85rem);
}

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

.section-intro {
  color: var(--text-muted);
  margin-bottom: 28px;
}

/* Feature / category grids */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

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

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 45, 106, 0.45);
}

.card img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.card-body {
  padding: 16px 18px 20px;
}

.card-body h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
}

.card-body p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.92rem;
}

.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  align-items: center;
  margin-bottom: 40px;
}

.feature-row:nth-child(even) .feature-media {
  order: 2;
}

.feature-row:nth-child(even) .feature-text {
  order: 1;
}

.feature-media img {
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.feature-text h3 {
  margin: 0 0 12px;
  font-size: 1.3rem;
}

.feature-text p {
  margin: 0 0 12px;
  color: var(--text-muted);
}

.feature-text ul {
  margin: 0;
  padding-left: 1.2em;
  color: var(--text-muted);
}

.feature-text li {
  margin-bottom: 6px;
}

/* SEO longform */
.seo-article {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 32px;
}

.seo-article h2 {
  margin-top: 0;
  font-size: 1.5rem;
}

.seo-article h3 {
  margin: 28px 0 12px;
  font-size: 1.2rem;
  color: #ff8fa8;
}

.seo-article p {
  color: var(--text-muted);
  margin: 0 0 14px;
}

.seo-article ul,
.seo-article ol {
  color: var(--text-muted);
  margin: 0 0 16px;
  padding-left: 1.25em;
}

.seo-article li {
  margin-bottom: 8px;
}

.seo-article a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.inline-thumbs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin: 20px 0;
}

.inline-thumbs img {
  border-radius: 10px;
  border: 1px solid var(--border);
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

/* Steps */
.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  counter-reset: step;
}

.step {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  position: relative;
}

.step::before {
  counter-increment: step;
  content: counter(step);
  display: inline-flex;
  width: 32px;
  height: 32px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--grad);
  color: #fff;
  font-weight: 700;
  font-size: 0.9rem;
  margin-bottom: 12px;
}

.step h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
}

.step p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.92rem;
}

/* FAQ */
.faq details {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 18px;
  margin-bottom: 10px;
}

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

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

.faq details p {
  margin: 12px 0 4px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Page hero (inner) */
.page-hero {
  padding: 40px 0 24px;
  border-bottom: 1px solid var(--border);
  background:
    radial-gradient(ellipse 60% 80% at 90% 0%, rgba(255, 45, 106, 0.12), transparent 50%),
    var(--bg);
}

.page-hero h1 {
  margin: 0 0 10px;
  font-size: clamp(1.5rem, 3vw, 2rem);
}

.page-hero p {
  margin: 0;
  color: var(--text-muted);
  max-width: 42em;
}

.breadcrumb {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 12px;
}

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

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

.content-page {
  padding: 36px 0 64px;
}

.content-block {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 32px;
}

.content-block h2 {
  margin: 28px 0 12px;
  font-size: 1.25rem;
  color: #ff8fa8;
}

.content-block h2:first-child {
  margin-top: 0;
}

.content-block p,
.content-block li {
  color: var(--text-muted);
}

.content-block ul {
  padding-left: 1.25em;
}

/* Error pages */
.error-page {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 48px 16px;
}

.error-page h1 {
  font-size: clamp(3rem, 10vw, 5rem);
  margin: 0 0 8px;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.error-page p {
  color: var(--text-muted);
  margin: 0 0 24px;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  background: #070709;
  padding: 40px 0 28px;
  margin-top: 20px;
}

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

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  color: var(--text);
  font-weight: 700;
}

.footer-brand img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
}

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

.footer-grid h4 {
  margin: 0 0 12px;
  font-size: 0.95rem;
}

.footer-links {
  list-style: none;
  margin: 0;
  padding: 0;
}

.footer-links li {
  margin-bottom: 8px;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-links a:hover {
  color: var(--pink);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 18px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 10px;
  color: var(--text-muted);
  font-size: 0.85rem;
}

.age-note {
  display: inline-block;
  margin-top: 16px;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  color: var(--text-muted);
  font-size: 0.88rem;
  background: rgba(255, 45, 106, 0.06);
}

/* Animations */
@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-copy,
.hero-visual {
  animation: rise 0.7s ease both;
}

.hero-visual {
  animation-delay: 0.12s;
}

.card,
.step,
.feature-row {
  animation: rise 0.55s ease both;
}

/* Mobile */
@media (max-width: 900px) {
  .nav-toggle {
    display: inline-flex;
  }

  .nav-menu {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    flex-direction: column;
    background: rgba(12, 12, 16, 0.98);
    border-bottom: 1px solid var(--border);
    padding: 12px 16px 18px;
    gap: 12px;
  }

  .nav-menu.open {
    display: flex;
  }

  .hero-grid,
  .feature-row,
  .grid-2,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .feature-row:nth-child(even) .feature-media,
  .feature-row:nth-child(even) .feature-text {
    order: initial;
  }

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

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

  .hero {
    padding: 36px 0 32px;
  }

  .hero-float {
    width: 38%;
    right: 8px;
    bottom: -8px;
  }

  .inline-thumbs {
    grid-template-columns: 1fr;
  }

  .seo-article,
  .content-block {
    padding: 20px 18px;
  }

  .section {
    padding: 40px 0;
  }
}

@media (max-width: 520px) {
  .grid-4 {
    grid-template-columns: 1fr;
  }

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

  .btn {
    width: 100%;
  }
}