:root{
  --bk-bg:#111827;
  --bk-bg-soft:#1a2334;
  --bk-bg-card:#1f2a3d;
  --bk-line:#2e3b52;
  --bk-text:#e5e7eb;
  --bk-muted:#aeb8c7;
  --bk-accent:#22d3ee;
  --bk-accent-dark:#0e7490;
  --bk-hi:#67e8f9;
  --bk-on-accent:#052833;
  --bk-radius:14px;
  --bk-font-body:"IBM Plex Sans",system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;
  --bk-font-display:"Chakra Petch","IBM Plex Sans",system-ui,sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  background:var(--bk-bg);
  color:var(--bk-text);
  font-family:var(--bk-font-body);
  font-size:1.0625rem;
  line-height:1.65;
}
img{max-width:100%;height:auto;display:block}
a{color:var(--bk-hi)}
a:hover{color:var(--bk-accent)}
a:focus-visible,button:focus-visible,summary:focus-visible{
  outline:3px solid var(--bk-hi);
  outline-offset:3px;
  border-radius:6px;
}
h1,h2,h3{font-family:var(--bk-font-display);line-height:1.2;color:#fff;margin:0 0 .6em}
h1{font-size:2rem}
h2{font-size:1.55rem}
h3{font-size:1.15rem}
p{margin:0 0 1em}
.bk-wrap{max-width:1180px;margin:0 auto;padding:0 1.1rem}
.bk-section{padding:3rem 0}
.bk-kicker{
  display:inline-block;
  font-family:var(--bk-font-display);
  font-size:.8rem;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--bk-on-accent);
  background:var(--bk-accent);
  border-radius:999px;
  padding:.3rem .9rem;
  margin-bottom:1rem;
}
.bk-lead{color:var(--bk-muted);max-width:62ch}
/* ---------- header ---------- */
.bk-header{
  position:sticky;top:0;z-index:50;
  background:rgba(17,24,39,.96);
  border-bottom:1px solid var(--bk-line);
}
.bk-header-in{display:flex;align-items:center;gap:1rem;min-height:64px}
.bk-brand{font-family:var(--bk-font-display);font-weight:700;font-size:1.3rem;color:#fff;text-decoration:none;white-space:nowrap}
.bk-brand b{color:var(--bk-accent);font-weight:700}
.bk-brand-mark{display:inline-block;width:.7em;height:.7em;margin-right:.45em;background:var(--bk-accent);
  clip-path:polygon(0 0,100% 50%,0 100%);vertical-align:baseline}
.bk-nav{display:none}
.bk-nav ul{display:flex;gap:1.1rem;list-style:none;margin:0;padding:0}
.bk-nav a{color:var(--bk-text);text-decoration:none;font-size:.95rem}
.bk-nav a:hover{color:var(--bk-hi)}
.bk-header-cta{margin-left:auto;display:none}
.bk-burger{
  margin-left:auto;
  background:transparent;border:1px solid var(--bk-line);border-radius:10px;
  width:44px;height:44px;display:inline-flex;align-items:center;justify-content:center;cursor:pointer;
}
.bk-burger svg{width:22px;height:22px;stroke:var(--bk-text)}
.bk-mobile-nav{display:none;border-top:1px solid var(--bk-line);padding:.6rem 1.1rem 1rem}
.bk-mobile-nav.open{display:block}
.bk-mobile-nav a{display:block;color:var(--bk-text);text-decoration:none;padding:.55rem 0;border-bottom:1px solid var(--bk-line)}
.bk-lang{position:relative}
.bk-lang summary{cursor:pointer;list-style:none;border:1px solid var(--bk-line);border-radius:999px;padding:.35rem .9rem;font-size:.9rem;color:var(--bk-text)}
.bk-lang summary::-webkit-details-marker{display:none}
.bk-lang-menu{position:absolute;right:0;top:calc(100% + 8px);background:var(--bk-bg-card);border:1px solid var(--bk-line);
  border-radius:12px;padding:.5rem;min-width:170px;z-index:60}
.bk-lang-menu a{display:block;padding:.4rem .7rem;border-radius:8px;color:var(--bk-text);text-decoration:none;font-size:.92rem}
.bk-lang-menu a:hover{background:var(--bk-bg-soft)}
/* ---------- buttons ---------- */
.bk-btn{
  display:inline-block;font-family:var(--bk-font-display);font-weight:700;text-decoration:none;
  border-radius:12px;padding:.85rem 1.6rem;font-size:1rem;border:2px solid transparent;cursor:pointer;
}
.bk-btn-solid{background:var(--bk-accent);color:var(--bk-on-accent)}
.bk-btn-solid:hover{background:var(--bk-hi);color:var(--bk-on-accent)}
.bk-btn-ghost{background:transparent;color:var(--bk-hi);border-color:var(--bk-accent-dark)}
.bk-btn-ghost:hover{border-color:var(--bk-accent);color:var(--bk-accent)}
.bk-btn-row{display:flex;flex-wrap:wrap;gap:.8rem;margin:1.4rem 0}
/* ---------- hero ---------- */
.bk-hero{padding:2.6rem 0 2.2rem}
.bk-hero-grid{display:grid;gap:1.8rem;align-items:center}
.bk-hero figure{margin:0}
.bk-hero img{border-radius:var(--bk-radius);border:1px solid var(--bk-line);width:100%}
.bk-hero-sub{color:var(--bk-muted);font-size:1.12rem;max-width:56ch}
.bk-chips{display:grid;gap:.7rem;margin:1.4rem 0 0;padding:0;list-style:none}
.bk-chip{
  display:flex;align-items:center;gap:.7rem;background:var(--bk-bg-card);
  border:1px solid var(--bk-line);border-radius:12px;padding:.7rem .9rem;font-size:.95rem;
}
.bk-chip svg{width:26px;height:26px;stroke:var(--bk-accent);flex:none}
/* ---------- stats bar ---------- */
.bk-stats{background:var(--bk-bg-soft);border-top:1px solid var(--bk-line);border-bottom:1px solid var(--bk-line)}
.bk-stats-grid{display:grid;gap:1rem;padding:1.6rem 0}
.bk-stat{display:flex;gap:.8rem;align-items:flex-start;background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:12px;padding:1rem}
.bk-stat svg{width:30px;height:30px;stroke:var(--bk-accent);flex:none}
.bk-stat strong{display:block;color:#fff;font-family:var(--bk-font-display)}
.bk-stat span{color:var(--bk-muted);font-size:.95rem}
/* ---------- cards & grids ---------- */
.bk-grid{display:grid;gap:1rem}
.bk-card{background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:var(--bk-radius);padding:1.3rem}
.bk-card h3{color:#fff}
.bk-card p{color:var(--bk-muted);font-size:.97rem;margin:0}
.bk-card svg.bk-ico{width:30px;height:30px;stroke:var(--bk-accent);margin-bottom:.6rem}
.bk-tiles{display:grid;gap:1rem}
.bk-tile{background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:var(--bk-radius);overflow:hidden}
.bk-tile img{width:100%;aspect-ratio:1/1;object-fit:cover}
.bk-tile-body{padding:1rem 1.1rem}
.bk-tile-body h3{margin-bottom:.3rem}
.bk-tile-body p{color:var(--bk-muted);font-size:.95rem;margin:0}
.bk-steps{display:grid;gap:1rem;counter-reset:bkstep}
.bk-step{background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:var(--bk-radius);padding:1.3rem;position:relative}
.bk-step-num{
  display:inline-flex;align-items:center;justify-content:center;width:38px;height:38px;border-radius:50%;
  background:var(--bk-accent);color:var(--bk-on-accent);font-family:var(--bk-font-display);font-weight:700;margin-bottom:.7rem;
}
.bk-step p{color:var(--bk-muted);margin:0}
/* ---------- pricing ---------- */
.bk-plans{display:grid;gap:1rem}
.bk-plan{background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:var(--bk-radius);padding:1.5rem;display:flex;flex-direction:column}
.bk-plan-hot{border:2px solid var(--bk-accent);position:relative}
.bk-flag{
  align-self:flex-start;background:var(--bk-accent);color:var(--bk-on-accent);
  font-family:var(--bk-font-display);font-size:.78rem;font-weight:700;letter-spacing:.08em;text-transform:uppercase;
  border-radius:999px;padding:.28rem .85rem;margin-bottom:.8rem;
}
.bk-price{font-family:var(--bk-font-display);font-size:2.1rem;color:#fff;font-weight:700}
.bk-per{color:var(--bk-hi);margin:.1rem 0 .3rem}
.bk-note{color:var(--bk-muted);font-size:.92rem;margin:0 0 .8rem}
.bk-plan ul{list-style:none;margin:0 0 1.2rem;padding:0;color:var(--bk-muted);font-size:.95rem}
.bk-plan li{padding:.3rem 0 .3rem 1.6rem;position:relative}
.bk-plan li::before{content:"";position:absolute;left:0;top:.75em;width:.8em;height:.45em;
  border-left:3px solid var(--bk-accent);border-bottom:3px solid var(--bk-accent);transform:rotate(-45deg) translateY(-50%)}
.bk-plan .bk-btn{margin-top:auto;text-align:center}
/* ---------- logo strips & posters ---------- */
.bk-logos{display:grid;grid-template-columns:repeat(2,1fr);gap:.8rem;list-style:none;margin:1.4rem 0;padding:0}
.bk-logos li{background:#fff;border-radius:10px;display:flex;align-items:center;justify-content:center;padding:.6rem;min-height:74px}
.bk-logos img{max-height:46px;width:auto;object-fit:contain}
.bk-posters{display:grid;grid-template-columns:repeat(3,1fr);gap:.7rem;margin:1.4rem 0}
.bk-posters figure{margin:0;background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:10px;overflow:hidden}
.bk-posters img{width:100%;aspect-ratio:2/3;object-fit:cover}
.bk-covers{display:grid;grid-template-columns:repeat(2,1fr);gap:.8rem;margin:1.4rem 0}
.bk-covers figure{margin:0;background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:10px;overflow:hidden}
.bk-covers img{width:100%;aspect-ratio:2/3;object-fit:cover}
.bk-device-banner{border-radius:var(--bk-radius);border:1px solid var(--bk-line);margin:1.4rem 0}
/* ---------- reviews ---------- */
.bk-quotes{display:grid;gap:1rem}
.bk-quote{background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:var(--bk-radius);padding:1.4rem}
.bk-quote blockquote{margin:0 0 .9rem;color:var(--bk-text)}
.bk-stars{display:flex;gap:.2rem;margin-bottom:.8rem}
.bk-stars svg{width:18px;height:18px;fill:var(--bk-accent)}
.bk-who{color:var(--bk-muted);font-size:.92rem}
/* ---------- faq ---------- */
.bk-faq details{background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:12px;margin-bottom:.7rem}
.bk-faq summary{cursor:pointer;padding:1rem 1.2rem;font-family:var(--bk-font-display);font-weight:600;color:#fff;list-style:none}
.bk-faq summary::-webkit-details-marker{display:none}
.bk-faq summary::after{content:"+";float:right;color:var(--bk-accent);font-size:1.3rem;line-height:1}
.bk-faq details[open] summary::after{content:"–"}
.bk-faq details p{padding:0 1.2rem 1.1rem;color:var(--bk-muted);margin:0}
/* ---------- final cta / seo / footer ---------- */
.bk-final{background:linear-gradient(135deg,#0b3540,#111827 70%);border-top:1px solid var(--bk-accent-dark);border-bottom:1px solid var(--bk-accent-dark);text-align:center}
.bk-final p{color:var(--bk-muted);max-width:56ch;margin:0 auto 1.4rem}
.bk-seo p{color:var(--bk-muted)}
.bk-footer{border-top:1px solid var(--bk-line);background:#0c1322;padding:2.4rem 0 1.6rem;font-size:.95rem}
.bk-footer-grid{display:grid;gap:1.6rem}
.bk-footer a{color:var(--bk-muted);text-decoration:none}
.bk-footer a:hover{color:var(--bk-hi)}
.bk-footer h3{font-size:1rem;color:#fff}
.bk-footer ul{list-style:none;margin:0;padding:0}
.bk-footer li{margin:.35rem 0}
.bk-langs{display:flex;flex-wrap:wrap;gap:.4rem 1rem;list-style:none;margin:0;padding:0}
.bk-base{border-top:1px solid var(--bk-line);margin-top:1.8rem;padding-top:1.2rem;color:var(--bk-muted);font-size:.88rem}
/* ---------- breakpoints ---------- */
@media (min-width:768px){
  h1{font-size:2.6rem}
  h2{font-size:1.9rem}
  .bk-hero-grid{grid-template-columns:1fr 1.1fr}
  .bk-chips{grid-template-columns:repeat(3,1fr)}
  .bk-stats-grid{grid-template-columns:repeat(2,1fr)}
  .bk-grid-2{grid-template-columns:repeat(2,1fr)}
  .bk-grid-3{grid-template-columns:repeat(3,1fr)}
  .bk-tiles{grid-template-columns:repeat(3,1fr)}
  .bk-steps{grid-template-columns:repeat(3,1fr)}
  .bk-plans{grid-template-columns:repeat(2,1fr)}
  .bk-quotes{grid-template-columns:repeat(3,1fr)}
  .bk-logos{grid-template-columns:repeat(4,1fr)}
  .bk-posters{grid-template-columns:repeat(6,1fr)}
  .bk-covers{grid-template-columns:repeat(3,1fr)}
  .bk-nav{display:block}
  .bk-burger,.bk-mobile-nav{display:none}
  .bk-header-cta{display:inline-block;margin-left:0}
  .bk-footer-grid{grid-template-columns:1.4fr 1fr 1fr}
}
@media (min-width:1280px){
  .bk-section{padding:4rem 0}
  .bk-plans{grid-template-columns:repeat(4,1fr)}
  .bk-stats-grid{grid-template-columns:repeat(4,1fr)}
  .bk-posters{grid-template-columns:repeat(6,1fr)}
}
/* ---------- install guide ---------- */
.bk-toc{list-style:none;margin:1.4rem 0;padding:0;display:grid;gap:.55rem}
.bk-toc li{margin:0}
.bk-toc a{display:block;background:var(--bk-bg-card);border:1px solid var(--bk-line);border-radius:10px;padding:.6rem .9rem;color:var(--bk-text);text-decoration:none;font-size:.95rem}
.bk-toc a:hover{border-color:var(--bk-accent);color:var(--bk-hi)}
.bk-guide-ol{margin:1.2rem 0 1.2rem 1.3rem;padding:0;color:var(--bk-muted);display:grid;gap:.6rem}
.bk-guide-ol li{padding-left:.3rem}
.bk-guide-ol li::marker{color:var(--bk-accent);font-family:var(--bk-font-display);font-weight:700}
@media (min-width:768px){
.bk-toc{grid-template-columns:repeat(2,1fr)}
}
/* ---------- print ---------- */
@media print{
  body{background:#fff;color:#000;font-size:11pt}
  h1,h2,h3{color:#000}
  .bk-header,.bk-final .bk-btn-row,.bk-btn-row,.bk-mobile-nav,.bk-lang{display:none}
  .bk-card,.bk-plan,.bk-quote,.bk-tile,.bk-faq details{border:1px solid #999;background:#fff;break-inside:avoid}
  a{color:#000;text-decoration:underline}
  .bk-section{padding:1rem 0}
}
@media (max-width:479px){.bk-header-in{gap:.55rem}.bk-brand{font-size:1.1rem}.bk-lang summary{padding:.3rem .6rem;font-size:.85rem}}
@media (max-width:767px){.bk-header-cta{display:none}}