/* ===========================================================================
   BD AI Pro — Premium design system (v2)
   Clean, modern, professional. Soft shadows, gradient accents, refined type.
   Bengali-first typography.
   ========================================================================= */
:root{
  /* base palette */
  --ink:#0F1115; --ink2:#1A1D24; --paper:#FAFAF9; --paper2:#F3F2EF; --surface:#ffffff;
  --muted:#6B7280; --muted2:#9CA3AF; --border:#E5E7EB; --border2:#EDEDEC;

  /* brand families */
  --gpt:#10A37F; --gptL:#E6F7F1; --gptD:#0D8A6C;
  --claude:#D97757; --claudeL:#FBEEE7; --claudeD:#C25E3F;
  --gemini:#4F6BED; --geminiL:#EBEFFC; --geminiD:#3D54C9;

  /* accent */
  --gold:#F5B729; --coral:#EF5A4C; --lilac:#8B6CEF; --teal:#0EA5A0;

  /* primary brand gradient */
  --grad-primary: linear-gradient(135deg,#4F6BED 0%,#8B6CEF 100%);
  --grad-warm: linear-gradient(135deg,#F5B729 0%,#EF5A4C 100%);
  --grad-dark: linear-gradient(135deg,#0F1115 0%,#272B33 100%);

  /* shadows — soft, layered, professional */
  --shadow-xs: 0 1px 2px rgba(15,17,21,.04);
  --shadow-sm: 0 2px 8px rgba(15,17,21,.06), 0 1px 2px rgba(15,17,21,.04);
  --shadow-md: 0 8px 24px rgba(15,17,21,.08), 0 2px 6px rgba(15,17,21,.04);
  --shadow-lg: 0 16px 48px rgba(15,17,21,.12), 0 4px 12px rgba(15,17,21,.06);
  --shadow-glow: 0 8px 32px rgba(79,107,237,.18);

  --r-sm:10px; --r:16px; --r-lg:24px; --r-xl:32px;
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;overflow-x:hidden}
body{font-family:'Hind Siliguri','Noto Sans Bengali',system-ui,sans-serif;background:var(--paper);color:var(--ink);line-height:1.7;-webkit-font-smoothing:antialiased}
h1,h2,h3,h4{font-family:'Noto Sans Bengali','Hind Siliguri',sans-serif;font-weight:700;line-height:1.15;letter-spacing:-.01em;color:var(--ink)}
a{color:inherit;text-decoration:none}
img{max-width:100%}
.wrap{max-width:1180px;margin:0 auto;padding:0 24px}
.kicker{display:inline-flex;align-items:center;gap:6px;font-weight:700;font-size:12.5px;letter-spacing:.06em;text-transform:uppercase;color:var(--gemini);background:var(--geminiL);padding:6px 14px;border-radius:999px}
.kicker::before{content:"";width:6px;height:6px;border-radius:50%;background:var(--gemini)}

/* ---------- buttons ---------- */
.btn{display:inline-flex;align-items:center;gap:8px;font-family:inherit;font-weight:700;font-size:15px;
  border:1.5px solid var(--border);border-radius:12px;padding:12px 22px;background:#fff;color:var(--ink);
  cursor:pointer;box-shadow:var(--shadow-xs);transition:all .18s cubic-bezier(.2,.7,.3,1);white-space:nowrap;flex-shrink:0}
.btn:hover{transform:translateY(-1px);box-shadow:var(--shadow-sm);border-color:#D1D5DB}
.btn:active{transform:translateY(0)}
.btn-primary{background:var(--grad-dark);color:#fff;border-color:transparent;box-shadow:var(--shadow-md)}
.btn-primary:hover{box-shadow:var(--shadow-lg);transform:translateY(-2px)}
.btn-accent{background:var(--grad-primary);color:#fff;border-color:transparent;box-shadow:var(--shadow-glow)}
.btn-accent:hover{box-shadow:0 12px 36px rgba(79,107,237,.28);transform:translateY(-2px)}
.btn-gold{background:linear-gradient(135deg,#F5B729,#EF5A4C);color:#fff;border-color:transparent;box-shadow:0 8px 28px rgba(245,183,41,.3)}
.btn-gold:hover{transform:translateY(-2px);box-shadow:0 12px 36px rgba(245,183,41,.4)}
.btn-sm{padding:9px 18px;font-size:13.5px;border-radius:10px}
.btn-lg{padding:15px 30px;font-size:16.5px;border-radius:14px}
.btn.active{background:var(--ink);color:#fff;border-color:var(--ink)}

/* ---------- announce + marquee ---------- */
.announce{background:var(--grad-dark);color:#fff;text-align:center;padding:11px 16px;font-size:13.5px;font-weight:600;letter-spacing:.01em}
.announce a{text-decoration:underline;font-weight:700;color:#F5B729}
.marquee{overflow:hidden;background:var(--ink);padding:0}
.marquee-track{
  display:inline-flex;white-space:nowrap;padding:13px 0;font-weight:700;font-size:14px;
  color:rgba(255,255,255,.55);letter-spacing:.02em;
  animation:marq 28s linear infinite !important;
  animation-play-state:running !important;
  will-change:transform;
}
.marquee-track span{display:inline-flex;flex-shrink:0;padding-right:50px}
.marquee-track b{color:#fff}
@keyframes marq{from{transform:translateX(0)}to{transform:translateX(-50%)}}

/* ---------- nav ---------- */
header.nav{position:sticky;top:0;z-index:60;background:rgba(250,250,249,.85);backdrop-filter:blur(12px);border-bottom:1px solid var(--border)}
.nav-in{display:flex;align-items:center;justify-content:space-between;min-height:72px;flex-wrap:nowrap}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:19px;letter-spacing:-.01em}
.logo{width:32px;height:32px;border-radius:9px;background:var(--grad-primary);position:relative;flex:0 0 auto;box-shadow:0 4px 14px rgba(79,107,237,.35)}
.logo::after{content:"";position:absolute;width:8px;height:8px;border-radius:50%;background:#fff;top:7px;right:7px;opacity:.9}
.bdaipro-logo-img{height:36px;width:auto;max-width:160px;border-radius:8px;object-fit:contain;flex:0 0 auto}
nav.links{display:flex;gap:2px;font-size:14.5px;font-weight:600}
nav.links a{padding:9px 15px;border-radius:10px;color:#4B5563;transition:.15s}
nav.links a:hover{background:var(--paper2);color:var(--ink)}
.nav-cta{display:flex;gap:10px;align-items:center;flex-shrink:0}
nav.links{flex-shrink:1;min-width:0;overflow:hidden}
.burger{display:none;background:#fff;border:1.5px solid var(--border);border-radius:10px;font-size:19px;line-height:1;cursor:pointer;width:42px;height:42px;box-shadow:var(--shadow-xs)}

/* ---------- header search ---------- */
.search-toggle{display:grid;place-items:center;flex-shrink:0;background:#fff;border:1.5px solid var(--border);border-radius:10px;width:42px;height:42px;color:var(--ink);cursor:pointer;box-shadow:var(--shadow-xs);transition:all .18s cubic-bezier(.2,.7,.3,1)}
.search-toggle:hover{border-color:#D1D5DB;box-shadow:var(--shadow-sm);transform:translateY(-1px)}
.search-toggle.active{background:var(--ink);border-color:var(--ink);color:#fff}

.search-panel{
  display:none;
  position:absolute;
  top:100%;left:0;right:0;
  background:#fff;
  border-bottom:1px solid var(--border);
  box-shadow:var(--shadow-md);
  z-index:59;
}
.search-panel.open{display:block}
.search-panel-in{padding:16px 24px}
.search-form{display:flex;align-items:center;gap:10px;position:relative}
.search-form-icon{position:absolute;left:14px;color:var(--muted2);pointer-events:none}
.search-form-input{
  flex:1;min-width:0;
  font-family:inherit;font-size:15px;color:var(--ink);
  border:1.5px solid var(--border);border-radius:12px;
  padding:11px 16px 11px 42px;background:var(--paper2);
  transition:.15s;
}
.search-form-input:focus{outline:none;border-color:var(--gemini);background:#fff;box-shadow:0 0 0 3px var(--geminiL)}
.search-form-input::placeholder{color:var(--muted2)}
.search-close{display:grid;place-items:center;flex-shrink:0;width:38px;height:38px;border:0;background:transparent;color:var(--muted);font-size:16px;cursor:pointer;border-radius:10px;transition:.15s}
.search-close:hover{background:var(--paper2);color:var(--ink)}
@media(max-width:560px){
  .search-form .btn{display:none}
  .search-form-input{padding-left:40px}
}

/* ---------- hero ---------- */
.hero{position:relative;padding:96px 0 100px;overflow:hidden;background:
  radial-gradient(ellipse 800px 500px at 85% -10%, rgba(79,107,237,.10), transparent),
  radial-gradient(ellipse 600px 400px at 10% 10%, rgba(217,119,87,.08), transparent)}
.hero .wrap{position:relative;z-index:2}
.hero h1{font-size:clamp(38px,6.2vw,72px);max-width:15ch;margin-bottom:24px;font-weight:800}
.hero h1 .hl{position:relative;white-space:nowrap;background:var(--grad-primary);-webkit-background-clip:text;background-clip:text;color:transparent}
.hero .sub{font-size:clamp(16px,2vw,19px);max-width:600px;color:var(--muted);margin-bottom:34px;line-height:1.65}
.hero .cta-row{display:flex;gap:14px;flex-wrap:wrap;margin-bottom:38px}
.proof{display:flex;gap:12px;flex-wrap:wrap}
.proof span{display:inline-flex;align-items:center;gap:6px;background:#fff;border:1px solid var(--border);border-radius:999px;padding:9px 16px;font-size:13.5px;font-weight:600;color:var(--ink2);box-shadow:var(--shadow-xs)}
.proof span::before{content:"✓";color:var(--gpt);font-weight:800}

/* floating blobs — soft gradient orbs */
.blob{position:absolute;z-index:1;animation:float 8s ease-in-out infinite;filter:blur(0px);opacity:.85}
.blob.b1{width:180px;height:180px;border-radius:50%;background:radial-gradient(circle at 30% 30%, var(--gptL), transparent 70%);top:40px;right:6%;animation-delay:0s}
.blob.b2{width:140px;height:140px;border-radius:42% 58% 65% 35%/45% 40% 60% 55%;background:radial-gradient(circle at 30% 30%, var(--claudeL), transparent 70%);bottom:60px;right:22%;animation-delay:1.4s}
.blob.b3{width:110px;height:110px;border-radius:50%;background:radial-gradient(circle at 30% 30%, var(--geminiL), transparent 70%);top:200px;right:32%;animation-delay:.7s}
.blob.b4{width:70px;height:70px;border-radius:18px;background:linear-gradient(135deg, var(--lilac), var(--gemini));bottom:140px;right:4%;transform:rotate(12deg);opacity:.18;animation-delay:2s}
@keyframes float{0%,100%{transform:translateY(0) rotate(0)}50%{transform:translateY(-16px) rotate(3deg)}}
.hero-art{position:absolute;right:-10px;top:50%;transform:translateY(-50%);width:42%;max-width:520px;z-index:1;opacity:.92;filter:drop-shadow(0 24px 48px rgba(15,17,21,.12))}

/* ---------- generic section ---------- */
section.block{padding:88px 0;position:relative;scroll-margin-top:80px}
.sec-head{max-width:760px;margin-bottom:48px}
.sec-head.center{margin-left:auto;margin-right:auto;text-align:center}
.sec-head h2{font-size:clamp(28px,4.2vw,46px);margin:16px 0 14px;font-weight:800}
.sec-head p{color:var(--muted);font-size:17px;max-width:60ch;line-height:1.65}
.block.cream{background:var(--paper2)}
.block.ink{background:var(--grad-dark);color:#fff}
.block.ink .sec-head p{color:rgba(255,255,255,.65)}
.block.mint{background:var(--gptL)} .block.peach{background:var(--claudeL)} .block.peri{background:var(--geminiL)}

/* ---------- editorial card (now: soft elevated card) ---------- */
.b-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--shadow-sm);transition:all .22s cubic-bezier(.2,.7,.3,1)}
.b-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:#D9DEE8}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.grid2{display:grid;grid-template-columns:repeat(2,1fr);gap:24px}

/* feature card */
.feat{padding:32px}
.feat .ic{width:56px;height:56px;border-radius:16px;display:grid;place-items:center;font-size:26px;margin-bottom:18px;box-shadow:var(--shadow-xs)}
.feat h3{font-size:21px;margin-bottom:10px;font-weight:700}
.feat p{color:var(--muted);font-size:15px;line-height:1.65}
.idx{font-size:13px;font-weight:700;color:var(--muted2);letter-spacing:.08em;margin-bottom:8px}

/* ---------- product showcase cards ---------- */
.show{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.pcard{overflow:hidden;display:flex;flex-direction:column}
.pcard .art{display:block;background:linear-gradient(135deg,var(--paper2),var(--paper))}
.pcard .art img{display:block;width:100%;padding:24px}
.pcard .body{padding:24px;display:flex;flex-direction:column;gap:9px;flex:1}
.pcard .fam-tag{align-self:flex-start;font-size:11.5px;font-weight:700;color:#fff;padding:4px 12px;border-radius:999px;letter-spacing:.02em}
.pcard h3{font-size:21px;font-weight:700}
.pcard p{color:var(--muted);font-size:14px;flex:1;line-height:1.6}
.pcard .row{display:flex;align-items:baseline;justify-content:space-between;margin-top:10px;padding-top:16px;border-top:1px solid var(--border2)}
.pcard .price{font-size:24px;font-weight:800;color:var(--ink)}
.pcard .strike{color:var(--muted2);text-decoration:line-through;font-size:13px;margin-left:6px}

/* ---------- steps ---------- */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.step{padding:32px;position:relative}
.step .num{width:48px;height:48px;border-radius:14px;background:var(--grad-primary);color:#fff;display:grid;place-items:center;font-weight:800;font-size:20px;margin-bottom:18px;box-shadow:var(--shadow-md)}
.step h3{font-size:19.5px;margin-bottom:9px;font-weight:700}.step p{color:var(--muted);font-size:14.5px;line-height:1.6}

/* ---------- pricing ---------- */
.toggle{display:flex;justify-content:center;margin-bottom:16px}
.toggle .pill{display:inline-flex;gap:4px;background:#fff;border:1px solid var(--border);border-radius:999px;padding:5px;box-shadow:var(--shadow-xs)}
.toggle button{border:0;background:transparent;padding:11px 24px;border-radius:999px;cursor:pointer;font-weight:700;color:var(--muted);font-family:inherit;font-size:14px;transition:.18s}
.toggle button.active{background:var(--ink);color:#fff;box-shadow:var(--shadow-sm)}
.toggle-note{text-align:center;color:var(--muted2);font-size:13px;margin-bottom:36px}
.fam{margin-bottom:48px}
.fam-title{display:flex;align-items:center;gap:12px;margin-bottom:8px;padding:14px 18px;border:1px solid var(--border);border-radius:16px;background:#fff;box-shadow:var(--shadow-xs)}
.fam-title .swatch{width:20px;height:20px;border-radius:7px}
.fam-title h3{font-size:20px;font-weight:700}
.fam-badge{font-size:11.5px;font-weight:700;padding:4px 12px;border-radius:999px;color:#fff;letter-spacing:.02em}
.fam-note{color:var(--muted);font-size:13.5px;margin:12px 0 18px 4px}
table{width:100%;border-collapse:separate;border-spacing:0;background:#fff;border:1px solid var(--border);border-radius:18px;overflow:hidden;box-shadow:var(--shadow-sm)}
thead th{color:#fff;text-align:right;padding:15px 18px;font-size:13.5px;font-weight:700;background:var(--ink2);letter-spacing:.01em}
thead th:first-child{text-align:left}
tbody td{padding:14px 18px;border-top:1px solid var(--border2);font-size:14.5px;text-align:right}
tbody td:first-child{text-align:left;font-weight:600}
tbody tr{transition:background .15s}
tbody tr:hover{background:var(--paper2)}
tbody tr:nth-child(even){background:rgba(243,242,239,.5)}
.list-price{color:var(--muted2);text-decoration:line-through;font-size:13px}
.our-price{font-weight:800;color:var(--ink)}
.save{display:inline-block;background:linear-gradient(135deg,#10A37F,#0EA5A0);color:#fff;font-size:11.5px;font-weight:700;padding:3px 11px;border-radius:999px}
.buy{background:var(--grad-primary);color:#fff;border:0;padding:8px 18px;border-radius:999px;font-weight:700;cursor:pointer;font-size:13px;font-family:inherit;box-shadow:0 4px 14px rgba(79,107,237,.25);transition:.18s}
.buy:hover{transform:translateY(-1px);box-shadow:0 8px 22px rgba(79,107,237,.35)}

/* ---------- big CTA band ---------- */
.cta-band{border-radius:var(--r-xl);background:var(--grad-dark);color:#fff;padding:64px;text-align:center;box-shadow:var(--shadow-lg);position:relative;overflow:hidden}
.cta-band::before{content:"";position:absolute;inset:0;background:radial-gradient(ellipse 600px 300px at 50% 0%, rgba(79,107,237,.25), transparent)}
.cta-band h2{font-size:clamp(28px,4vw,44px);margin-bottom:14px;position:relative;font-weight:800}
.cta-band p{font-size:17px;opacity:.75;margin-bottom:28px;position:relative}
.cta-band .btn{position:relative}

/* ---------- FAQ ---------- */
details{background:#fff;border:1px solid var(--border);border-radius:16px;margin-bottom:12px;overflow:hidden;box-shadow:var(--shadow-xs);transition:.18s}
details[open]{box-shadow:var(--shadow-sm)}
details summary{padding:19px 24px;cursor:pointer;font-weight:700;font-size:16px;list-style:none;display:flex;justify-content:space-between;align-items:center}
details summary::-webkit-details-marker{display:none}
details summary::after{content:"+";font-size:22px;color:var(--gemini);font-weight:400;transition:.2s}
details[open] summary::after{content:"−"}
details .ans{padding:0 24px 22px;color:var(--muted);font-size:15px;line-height:1.65}

/* ---------- footer ---------- */
footer{background:var(--ink);color:rgba(255,255,255,.65);padding:64px 0 28px}
.foot-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:32px;margin-bottom:40px}
footer h4{color:#fff;font-size:14px;margin-bottom:16px;font-weight:700;letter-spacing:.02em}
footer ul{list-style:none}footer li{margin-bottom:10px;font-size:14px}
footer li a{transition:.15s}
footer li a:hover{color:#fff}
.foot-bottom{border-top:1px solid rgba(255,255,255,.1);padding-top:22px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px;font-size:13px;opacity:.55}
footer .logo{background:var(--grad-primary)}
.foot-contact{margin-top:14px;display:flex;flex-direction:column;gap:8px}
.foot-contact a{display:inline-flex;align-items:center;gap:8px;font-size:14px;color:rgba(255,255,255,.75);transition:.15s ease}
.foot-contact a:hover{color:#fff}
.foot-contact svg{flex-shrink:0;opacity:.8}
.foot-social{display:flex;gap:10px;margin-top:16px}
.foot-social a{display:grid;place-items:center;width:38px;height:38px;border-radius:50%;background:rgba(255,255,255,.08);color:rgba(255,255,255,.75);transition:.18s ease}
.foot-social a:hover{background:var(--grad-primary,#00d4ff);color:#fff;transform:translateY(-2px)}
.foot-social svg{display:block}

/* ---------- scroll reveal ---------- */
.reveal{opacity:0;transform:translateY(24px);transition:opacity .7s cubic-bezier(.2,.7,.2,1),transform .7s cubic-bezier(.2,.7,.2,1)}
.reveal.in{opacity:1;transform:none}
@media(prefers-reduced-motion:reduce){.reveal{opacity:1;transform:none;transition:none}.blob{animation:none}}

/* ---------- crumb ---------- */
.crumb{color:var(--muted);font-size:13.5px;padding:24px 0 0}
.crumb a:hover{color:var(--ink);text-decoration:underline}

/* ---------- mobile ---------- */
.mobile-cta{display:none}
.nav-menu-wrap{display:contents}
@media(max-width:920px){
  .nav-menu-wrap{display:none}
  .burger{display:grid;place-items:center}
  .nav-menu-wrap.open{
    display:flex;
    flex-direction:column;
    position:absolute;
    top:72px;left:0;right:0;
    background:#fff;
    border-bottom:1px solid var(--border);
    padding:16px 24px 20px;
    gap:4px;
    box-shadow:var(--shadow-md);
    z-index:60;
  }
  .nav-menu-wrap.open nav.links{display:flex;flex-direction:column;gap:4px}
  .nav-menu-wrap.open .nav-cta{
    display:flex;
    flex-direction:column;
    gap:10px;
    margin-top:12px;
    padding-top:14px;
    border-top:1px solid var(--border);
  }
  .nav-menu-wrap.open .nav-cta .btn{display:flex;justify-content:center;width:100%}
  nav.links{position:static;background:none;border:0;box-shadow:none;padding:0}
  .grid3,.grid2,.steps,.show{grid-template-columns:1fr}
  .hero-art{display:none}
  .hero h1{max-width:100%}
  .foot-grid{grid-template-columns:1fr 1fr}
  table,thead,tbody,tr,td,th{display:block}
  thead{display:none}
  tbody tr{margin-bottom:14px;border-bottom:1px solid var(--border);border-radius:12px}
  tbody td{border:0;display:flex;justify-content:space-between;align-items:center;text-align:right;padding:10px 16px}
  tbody td:first-child{text-align:left}
  tbody td::before{content:attr(data-l);color:var(--muted);font-weight:700;text-align:left}
  .mobile-cta{display:flex;position:fixed;bottom:0;left:0;right:0;z-index:70;background:#fff;border-top:1px solid var(--border);padding:12px 16px;box-shadow:0 -8px 24px rgba(15,17,21,.08)}
  .mobile-cta .btn{flex:1;justify-content:center}
  body{padding-bottom:74px}
  .cta-band{padding:40px 24px}
}
@media(max-width:560px){.foot-grid{grid-template-columns:1fr}}

/* ---------- misc polish for product/guide pages ---------- */
.ph .badge{box-shadow:var(--shadow-sm)}
.ag{box-shadow:var(--shadow-xs)!important;border:1px solid var(--border)!important}
.shot,.shot2{box-shadow:var(--shadow-sm)!important;border:1px solid var(--border)!important}
.buybox{background:var(--grad-dark)!important;box-shadow:var(--shadow-lg)!important;border:0!important}
.hero-img{box-shadow:var(--shadow-md)!important;border:1px solid var(--border)!important}
.img-box{box-shadow:var(--shadow-xs)!important;border:1px solid var(--border)!important}
.toc{box-shadow:var(--shadow-sm)!important;border:1px solid var(--border)!important}
.step.h .n,.step .n,.stepd .n{background:var(--grad-primary)!important;color:#fff!important;box-shadow:var(--shadow-sm)!important;border:0!important}
.gtip{background:var(--gptL)!important;border:1px solid var(--border)!important;border-radius:14px!important}
.gwarn{background:var(--claudeL)!important;border:1px solid var(--border)!important;border-radius:14px!important}
table.tt{box-shadow:var(--shadow-sm)!important;border:1px solid var(--border)!important}
ul.ticks li::before{box-shadow:var(--shadow-xs)}