:root{
  --navy:#071d46;
  --gold:#c58a08;
  --orange:#f18a64;
  --cream:#fffaf2;
  --ink:#192236;
  --muted:#6f7684;
  --line:#e8e1d7;
  --white:#fff;
  --shadow:0 18px 50px rgba(7,29,70,.12);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:"Noto Sans Bengali",system-ui,sans-serif;color:var(--ink);background:#fff;line-height:1.7}
img{max-width:100%;display:block}
button,input,select,textarea{font:inherit}
.container{width:min(1140px,calc(100% - 36px));margin:auto}
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);backdrop-filter:blur(14px);border-bottom:1px solid rgba(7,29,70,.08)}
.nav{height:74px;display:flex;align-items:center;justify-content:space-between}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--navy);font-weight:800;font-size:1.15rem}
.brand img{width:48px;height:48px;object-fit:contain;border-radius:50%}
.nav-order{background:var(--navy);color:#fff;text-decoration:none;padding:10px 22px;border-radius:999px;font-weight:700}
.hero{background:radial-gradient(circle at 77% 30%,#fff0dd 0,transparent 28%),linear-gradient(135deg,#fffdf8,#fff7ea);padding:76px 0 68px;overflow:hidden}
.hero-grid{display:grid;grid-template-columns:1.1fr .9fr;align-items:center;gap:70px}
.eyebrow,.section-kicker{display:inline-block;color:var(--gold);font-weight:800;letter-spacing:.02em;margin-bottom:8px}
.hero h1{font-size:clamp(2.3rem,5vw,4.6rem);line-height:1.12;margin:0 0 12px;color:var(--navy);letter-spacing:-.03em}
.hero h1 em{font-style:normal;color:var(--orange)}
.subtitle{font-size:1.35rem;font-weight:700;margin:0 0 20px}
.lead{font-size:1.08rem;color:#4e5665;max-width:700px}
.price-row{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin:26px 0}
.old-price{text-decoration:line-through;color:#8b8f98;font-size:1.15rem}
.offer-price{font-size:1.65rem;font-weight:800;color:var(--navy)}
.save-badge{background:#fff1d4;color:#9a6500;padding:5px 10px;border-radius:999px;font-weight:700;font-size:.85rem}
.hero-actions{display:flex;gap:12px;flex-wrap:wrap}
.btn{border:0;display:inline-flex;align-items:center;justify-content:center;text-decoration:none;padding:14px 24px;border-radius:12px;font-weight:800;cursor:pointer;transition:.2s transform,.2s box-shadow}
.btn:hover{transform:translateY(-2px)}
.btn-primary{background:var(--navy);color:#fff;box-shadow:0 12px 28px rgba(7,29,70,.2)}
.btn-secondary{background:#fff;color:var(--navy);border:1px solid #d9d3ca}
.trust-strip{display:flex;gap:18px;flex-wrap:wrap;margin-top:24px;color:#515968;font-size:.92rem}
.book-showcase{position:relative;display:grid;place-items:center}
.book-showcase>img{position:relative;width:min(440px,86%);border-radius:7px;box-shadow:0 36px 70px rgba(40,28,16,.24);transform:perspective(900px) rotateY(-6deg)}
.book-glow{position:absolute;width:420px;height:420px;border-radius:50%;background:#ffd9a8;filter:blur(70px);opacity:.55}
.floating-card{position:absolute;right:0;bottom:12%;background:#fff;padding:14px 20px;border-radius:15px;box-shadow:var(--shadow);display:flex;flex-direction:column}
.floating-card strong{font-size:.85rem;color:#777}.floating-card span{font-size:1.55rem;font-weight:800;color:var(--navy)}
section{padding:90px 0}
.section-heading{text-align:center;max-width:760px;margin:0 auto 45px}
.section-heading span{color:var(--gold);font-weight:800}
.section-heading h2,.benefits-grid h2,.author-card h2,.order-copy h2{font-size:clamp(2rem,4vw,3.1rem);line-height:1.25;color:var(--navy);margin:8px 0 14px}
.problem-section{background:#fff}
.problem-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
.problem-grid article{padding:28px 24px;border:1px solid var(--line);border-radius:18px;background:#fff;box-shadow:0 10px 30px rgba(7,29,70,.05)}
.problem-grid article div{font-weight:800;color:var(--orange);font-size:1.8rem}
.problem-grid h3{color:var(--navy);line-height:1.35;margin:8px 0}
.problem-grid p{margin:0;color:var(--muted)}
.benefits-section{background:var(--cream)}
.benefits-grid{display:grid;grid-template-columns:.9fr 1.1fr;gap:70px;align-items:start}
.benefits-grid>div>p{color:var(--muted);font-size:1.05rem}
.benefit-list{list-style:none;margin:0;padding:0;display:grid;gap:14px}
.benefit-list li{background:#fff;border-radius:16px;padding:20px 22px;display:grid;gap:2px;border:1px solid #eee4d7}
.benefit-list b{color:var(--navy);font-size:1.08rem}
.benefit-list span{color:var(--muted)}
.inside-section{background:#fff}
.sample-gallery{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.sample-card{background:#fff;border:1px solid var(--line);border-radius:14px;padding:10px;cursor:pointer;box-shadow:0 8px 24px rgba(7,29,70,.07);overflow:hidden;text-align:left;color:var(--navy);font-weight:700}
.sample-card img{width:100%;height:280px;object-fit:cover;object-position:top;border-radius:9px;background:#f5f5f5}
.sample-card span{display:block;padding:9px 5px 3px}
.author-section{background:linear-gradient(135deg,#061a3e,#0c2d62);color:#fff}
.author-card{display:grid;grid-template-columns:100px 1fr;gap:30px;align-items:center}
.author-mark{font-family:Georgia,serif;font-size:9rem;line-height:.6;color:var(--gold)}
.author-card h2{color:#fff}.author-card p{max-width:820px;color:#dce3ee;font-size:1.05rem}
.order-section{background:#081d43;color:#fff}
.order-grid{display:grid;grid-template-columns:.9fr 1.1fr;gap:62px;align-items:start}
.section-kicker.light{color:#f2bd4a}
.order-copy h2{color:#fff}
.order-copy>p{color:#dce4ef;font-size:1.05rem}
.delivery-info{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:28px 0}
.delivery-info div{background:rgba(255,255,255,.08);padding:16px;border-radius:14px;display:flex;flex-direction:column}
.delivery-info span{color:#cbd5e4}.delivery-info strong{color:#fff}
.mini-summary{display:flex;align-items:center;gap:14px;background:#fff;color:var(--ink);padding:12px;border-radius:16px}
.mini-summary img{width:65px;height:92px;object-fit:cover;border-radius:5px}
.mini-summary div{display:flex;flex-direction:column}.mini-summary span{color:var(--orange);font-weight:800}
.order-form{background:#fff;color:var(--ink);padding:32px;border-radius:24px;box-shadow:0 28px 70px rgba(0,0,0,.25)}
.order-form h3{font-size:1.75rem;color:var(--navy);margin:0}
.form-note{margin-top:0;color:var(--muted);font-size:.9rem}
.order-form label{display:grid;gap:7px;font-weight:700;margin:15px 0}
.order-form input,.order-form select,.order-form textarea{width:100%;border:1px solid #dfe3e8;border-radius:10px;padding:12px 13px;background:#fbfcfe;outline:none}
.order-form input:focus,.order-form select:focus,.order-form textarea:focus{border-color:#617aa4;box-shadow:0 0 0 3px rgba(97,122,164,.14)}
.order-form small{font-weight:400;color:var(--muted)}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.order-total{border-top:1px solid #e5e7eb;margin-top:20px;padding-top:14px;display:grid;gap:8px}
.order-total div{display:flex;justify-content:space-between}
.order-total .grand{font-size:1.2rem;color:var(--navy);border-top:1px dashed #d6dae0;padding-top:10px;margin-top:4px}
.btn-submit{width:100%;background:linear-gradient(135deg,#c88904,#e6ac27);color:#fff;margin-top:18px;font-size:1.05rem}
.cod-note{text-align:center;color:var(--muted);font-size:.88rem;margin-bottom:0}
.form-message{display:none;margin-top:12px;padding:12px;border-radius:10px;font-weight:600}
.form-message.show{display:block}.form-message.success{background:#eaf8ef;color:#146c35}.form-message.error{background:#fff0ef;color:#9b2421}
footer{background:#04132e;color:#fff;padding:42px 0 18px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:30px;align-items:center}
.footer-brand{display:flex;gap:12px;align-items:center}.footer-brand img{width:58px;height:58px;object-fit:contain;border-radius:50%}
.footer-brand div,footer .footer-grid>div{display:flex;flex-direction:column}
footer span,footer a{color:#b9c6d8;text-decoration:none}.copyright{text-align:center;color:#7889a2;font-size:.85rem;margin-top:30px}
.lightbox{position:fixed;inset:0;background:rgba(2,9,22,.93);display:none;align-items:center;justify-content:center;padding:30px;z-index:100}
.lightbox.open{display:flex}.lightbox img{max-height:90vh;max-width:92vw;object-fit:contain}
.lightbox-close{position:absolute;right:24px;top:16px;background:none;border:0;color:#fff;font-size:3rem;cursor:pointer}
@media(max-width:900px){
 .hero-grid,.benefits-grid,.order-grid{grid-template-columns:1fr}
 .hero-copy{text-align:center}.lead{margin-left:auto;margin-right:auto}.hero-actions,.trust-strip,.price-row{justify-content:center}
 .book-showcase{margin-top:10px}.problem-grid{grid-template-columns:1fr 1fr}.sample-gallery{grid-template-columns:1fr 1fr}
 .order-copy{text-align:center}.mini-summary{text-align:left}.footer-grid{grid-template-columns:1fr 1fr}.footer-brand{grid-column:1/-1}
}
@media(max-width:600px){
 .container{width:min(100% - 24px,1140px)}.nav{height:64px}.brand span{display:none}
 .hero{padding-top:48px}.hero h1{font-size:2.55rem}.subtitle{font-size:1.1rem}.lead{font-size:1rem}
 section{padding:68px 0}.problem-grid,.sample-gallery,.delivery-info,.form-row,.footer-grid{grid-template-columns:1fr}
 .sample-card img{height:250px}.author-card{grid-template-columns:1fr}.author-mark{display:none}
 .order-form{padding:22px 17px;border-radius:18px}.footer-brand{grid-column:auto}
 .book-showcase>img{width:82%}.floating-card{right:2%;bottom:8%}
}