:root{
  --bg:#FFFFFF;
  --fg:#0F172A;
  --muted:#475569;
  --accent:#2A7B9A;
  --accent-700:#1F5E78;
  --secondary:#73A8B9;
  --tint:#ADDFEA;
  --border:#E5E7EB;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Noto Sans","Apple Color Emoji","Segoe UI Emoji";color:var(--fg);background:var(--bg);line-height:1.6;font-size:16px;}
a{color:var(--accent-700);text-decoration:none} a:hover{text-decoration:underline}
.container{max-width:1100px;margin:0 auto;padding:0 20px}
.header{position:sticky;top:0;background:#fff;border-bottom:1px solid var(--border);z-index:50}
.nav{display:flex;align-items:center;justify-content:space-between;padding:14px 0}
.brand{display:flex;align-items:center;gap:12px;color:inherit;text-decoration:none}
.brand img{height:56px;width:auto}
.nav a{margin-left:18px;color:var(--muted)} .nav a:hover{color:var(--fg)}
.hero{padding:72px 0 24px}
.hero-grid{display:grid;gap:28px;grid-template-columns:1fr}
@media(min-width:980px){ .hero-grid{grid-template-columns:1fr 1.1fr; align-items:center} }
h1{font-size:42px;line-height:1.15;margin:0 0 12px;font-weight:800;letter-spacing:-.5px}
h2{font-size:28px;margin:0 0 10px}
h3{margin-top:0}
p{margin:0 0 14px;color:var(--muted)}
.btn{display:inline-block;padding:12px 18px;border-radius:12px;border:1px solid var(--border);text-decoration:none;color:#fff;background:var(--accent);font-weight:600}
.btn:hover{filter:brightness(0.95)}
.card{border:1px solid var(--border);border-radius:16px;padding:18px;background:#fff}
.cards{display:grid;gap:18px}
@media(min-width:800px){ .cards{grid-template-columns:repeat(3,1fr)} }
.section{padding:36px 0;border-top:1px solid var(--border)}
.hero-logo{display:flex;align-items:center;justify-content:center}
.hero-logo img{width:100%;max-width:520px;height:auto}
.book-cover{width:100%;max-width:420px;height:auto;border-radius:10px;border:1px solid var(--border);box-shadow:0 10px 30px rgba(0,0,0,.06);margin:8px 0 10px}
.philo-image{width:100%;max-width:823px;height:auto;border-radius:10px;border:1px solid var(--border);box-shadow:0 10px 30px rgba(0,0,0,.06);margin:12px 0 2px}
footer{padding:26px 0;border-top:1px solid var(--border);color:var(--muted);font-size:14px}
.nav a.active{color:var(--fg);font-weight:700}