:root {
  --bg: #0a0a0c;
  --bg-soft: #121216;
  --bg-card: #1a1a20;
  --bg-elevated: #22222a;
  --text: #f2f2f5;
  --text-muted: #a0a0ab;
  --accent: #e63946;
  --accent-soft: #ff6b6b;
  --accent-dark: #c1121f;
  --border: rgba(255, 255, 255, 0.08);
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 12px 40px rgba(0, 0, 0, 0.45);
  --max: 1180px;
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-display: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.75;
  min-height: 100vh;
  padding-top: 70px;
  background-image:
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(230, 57, 70, 0.18), transparent),
    radial-gradient(ellipse 60% 40% at 100% 50%, rgba(230, 57, 70, 0.06), transparent),
    linear-gradient(180deg, #0a0a0c 0%, #0d0d12 100%);
}

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

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

a:hover {
  color: #fff;
}

ul {
  list-style: none;
}

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

/* Fixed top bar (header + ads) — reliable on mobile */
.fixed-top {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  width: 100%;
  z-index: 1000;
  background: #0a0a0c;
  -webkit-transform: translateZ(0);
  transform: translateZ(0);
}

/* Header */
.site-header {
  position: relative;
  top: auto;
  left: auto;
  right: auto;
  width: 100vw;
  z-index: 2;
  background: #0a0a0c;
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 0;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
  flex-shrink: 0;
}

.logo img {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  object-fit: cover;
}

.logo span {
  background: linear-gradient(90deg, #fff 40%, var(--accent-soft));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.nav {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.nav a {
  color: var(--text-muted);
  font-size: 0.92rem;
  padding: 8px 12px;
  border-radius: 999px;
}

.nav a:hover,
.nav a.active {
  color: #fff;
  background: rgba(230, 57, 70, 0.15);
}

.nav-toggle {
  display: none;
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: #fff;
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 1.2rem;
}

/* Hero */
.hero {
  padding: 48px 0 36px;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 36px;
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--accent-soft);
  background: rgba(230, 57, 70, 0.12);
  border: 1px solid rgba(230, 57, 70, 0.28);
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 18px;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 3.5vw, 2.6rem);
  line-height: 1.25;
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: 0.01em;
}

.hero h1 em {
  font-style: normal;
  color: var(--accent);
}

.hero-lead {
  color: var(--text-muted);
  font-size: 1.05rem;
  margin-bottom: 28px;
  max-width: 540px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 28px;
}

.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, background 0.2s ease;
}

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

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  color: #fff;
  box-shadow: 0 8px 24px rgba(230, 57, 70, 0.35);
}

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

.btn-ghost {
  background: var(--bg-card);
  color: #fff;
  border: 1px solid var(--border);
}

.btn-ghost:hover {
  color: #fff;
  border-color: rgba(230, 57, 70, 0.4);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  color: var(--text-muted);
  font-size: 0.88rem;
}

.hero-meta strong {
  color: #fff;
  display: block;
  font-size: 1.15rem;
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  width: 100%;
  border-radius: 18px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  max-height: 560px;
}

.hero-visual::after {
  content: "";
  position: absolute;
  inset: auto -12% -12% auto;
  width: 55%;
  height: 40%;
  background: radial-gradient(circle, rgba(230, 57, 70, 0.35), transparent 70%);
  z-index: -1;
  pointer-events: none;
}

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

.section-alt {
  background: linear-gradient(180deg, transparent, rgba(26, 26, 32, 0.65), transparent);
}

.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 36px;
}

.section-head .eyebrow {
  color: var(--accent-soft);
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  margin-bottom: 10px;
}

.section-head h2 {
  font-size: clamp(1.45rem, 2.8vw, 2rem);
  margin-bottom: 12px;
  line-height: 1.3;
}

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

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

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.feature-card:hover {
  border-color: rgba(230, 57, 70, 0.35);
  transform: translateY(-3px);
}

.feature-card .icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(230, 57, 70, 0.15);
  color: var(--accent-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  margin-bottom: 14px;
}

.feature-card h3 {
  font-size: 1.08rem;
  margin-bottom: 8px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.94rem;
}

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

.showcase-item {
  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;
}

.showcase-item:hover {
  transform: translateY(-4px);
  border-color: rgba(230, 57, 70, 0.4);
}

.showcase-item img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  background: var(--bg-soft);
}

.showcase-item figcaption {
  padding: 12px 14px 16px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.showcase-item figcaption strong {
  display: block;
  color: #fff;
  margin-bottom: 4px;
  font-size: 0.95rem;
}

/* Two column content */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: center;
}

.split.reverse .split-media {
  order: 2;
}

.split-media img {
  width: 100%;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  max-height: 520px;
  margin-inline: auto;
}

.split-copy h2 {
  font-size: clamp(1.35rem, 2.5vw, 1.85rem);
  margin-bottom: 14px;
}

.split-copy p {
  color: var(--text-muted);
  margin-bottom: 14px;
}

.split-copy ul {
  margin: 16px 0 20px;
}

.split-copy li {
  position: relative;
  padding-left: 18px;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.split-copy li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
}

/* Category chips */
.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 20px 0;
}

.chip {
  display: inline-block;
  padding: 8px 14px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--text-muted);
  font-size: 0.88rem;
}

.chip:hover {
  color: #fff;
  border-color: rgba(230, 57, 70, 0.4);
}

/* SEO long content */
.seo-article {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: clamp(24px, 4vw, 40px);
}

.seo-article h2 {
  font-size: 1.45rem;
  margin: 28px 0 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.seo-article h2:first-child {
  margin-top: 0;
}

.seo-article h3 {
  font-size: 1.12rem;
  margin: 22px 0 10px;
  color: #fff;
}

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

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

.seo-article ol,
.seo-article ul {
  margin: 12px 0 18px 1.2em;
  color: var(--text-muted);
}

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

.seo-article ol li {
  list-style: decimal;
}

.toc {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 18px 20px;
  margin-bottom: 24px;
}

.toc strong {
  display: block;
  margin-bottom: 10px;
  color: #fff;
}

.toc a {
  display: block;
  color: var(--text-muted);
  padding: 4px 0;
  font-size: 0.92rem;
}

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

/* Steps */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  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: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  font-size: 0.9rem;
  margin-bottom: 12px;
}

.step h3 {
  font-size: 1rem;
  margin-bottom: 8px;
}

.step p {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* FAQ */
.faq {
  display: grid;
  gap: 12px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
}

.faq-item h3 {
  font-size: 1.02rem;
  margin-bottom: 8px;
}

.faq-item p {
  color: var(--text-muted);
  font-size: 0.94rem;
}

/* CTA band */
.cta-band {
  margin: 20px 0 40px;
  padding: 40px 28px;
  border-radius: 18px;
  background:
    linear-gradient(135deg, rgba(230, 57, 70, 0.22), rgba(26, 26, 32, 0.9)),
    var(--bg-card);
  border: 1px solid rgba(230, 57, 70, 0.3);
  text-align: center;
}

.cta-band h2 {
  font-size: clamp(1.35rem, 2.5vw, 1.8rem);
  margin-bottom: 10px;
}

.cta-band p {
  color: var(--text-muted);
  margin-bottom: 22px;
  max-width: 560px;
  margin-inline: auto;
}

/* Page hero (inner pages) */
.page-hero {
  padding: 40px 0 20px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 36px;
}

.page-hero h1 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 10px;
}

.page-hero p {
  color: var(--text-muted);
  max-width: 680px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

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

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

.breadcrumb span {
  opacity: 0.5;
}

/* Legal / content pages */
.content-page {
  padding-bottom: 64px;
}

.content-body {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: clamp(24px, 4vw, 40px);
  max-width: 860px;
  margin: 0 auto;
}

.content-body h2 {
  font-size: 1.25rem;
  margin: 28px 0 12px;
}

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

.content-body p,
.content-body li {
  color: var(--text-muted);
  margin-bottom: 12px;
}

.content-body ul,
.content-body ol {
  margin: 8px 0 16px 1.2em;
}

.content-body li {
  list-style: disc;
  margin-bottom: 6px;
}

.content-body ol li {
  list-style: decimal;
}

.content-body .updated {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.related-links {
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.related-links h3 {
  font-size: 1rem;
  margin-bottom: 12px;
}

.related-links a {
  display: inline-block;
  margin: 0 14px 10px 0;
  color: var(--text-muted);
  font-size: 0.92rem;
}

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

/* Error pages */
.error-page {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 60px 20px;
}

.error-box {
  max-width: 520px;
}

.error-code {
  font-size: clamp(4rem, 12vw, 6.5rem);
  font-weight: 800;
  line-height: 1;
  background: linear-gradient(135deg, var(--accent), #fff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 12px;
}

.error-box h1 {
  font-size: 1.5rem;
  margin-bottom: 12px;
}

.error-box p {
  color: var(--text-muted);
  margin-bottom: 28px;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  background: #070709;
  padding: 48px 0 28px;
  margin-top: 40px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 36px;
}

.footer-brand .logo {
  margin-bottom: 12px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.9rem;
  max-width: 320px;
}

.footer-col h4 {
  font-size: 0.95rem;
  margin-bottom: 14px;
  color: #fff;
}

.footer-col a {
  display: block;
  color: var(--text-muted);
  font-size: 0.9rem;
  padding: 5px 0;
}

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

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: space-between;
  color: var(--text-muted);
  font-size: 0.85rem;
}

.keywords-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.keywords-bar span {
  font-size: 0.78rem;
  color: var(--text-muted);
  opacity: 0.7;
}

/* Animations */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

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

.showcase-item,
.feature-card,
.step {
  animation: fadeUp 0.55s ease both;
}

/* Mobile */
@media (max-width: 960px) {
  .hero-grid,
  .split,
  .split.reverse {
    grid-template-columns: 1fr;
  }

  .split.reverse .split-media {
    order: 0;
  }

  .feature-grid {
    grid-template-columns: 1fr 1fr;
  }

  .showcase-grid {
    grid-template-columns: 1fr 1fr;
  }

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

  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }

  .split-media img,
  .hero-visual img {
    max-height: 480px;
    width: min(100%, 360px);
    margin-inline: auto;
  }
}

@media (max-width: 720px) {
  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 101;
    max-height: calc(100vh - 70px);
    overflow-y: auto;
    background: rgba(12, 12, 16, 0.98);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    align-items: stretch;
    padding: 12px 16px 18px;
    gap: 4px;
    -webkit-overflow-scrolling: touch;
  }

  .nav.open {
    display: flex;
  }

  .nav a {
    padding: 12px 14px;
    border-radius: var(--radius-sm);
  }

  .header-inner {
    position: relative;
  }

  .hero {
    padding: 28px 0 20px;
  }

  .section {
    padding: 40px 0;
  }

  .feature-grid,
  .showcase-grid,
  .steps,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .showcase-grid {
    grid-template-columns: 1fr 1fr;
  }

  .hero-actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 420px) {
  .showcase-grid {
    grid-template-columns: 1fr;
  }

  .showcase-item img {
    max-height: 420px;
    margin-inline: auto;
  }
}