:root{--bg:#f6f8fb;--card:#fff;--text:#1d2733;--muted:#5d6b7a;--brand:#0b5fff;--brand-d:#0846c2;--line:#e2e8f0}
*{box-sizing:border-box}
body{margin:0;font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;background:var(--bg);color:var(--text);line-height:1.65}
a{color:var(--brand)}
.wrap{max-width:960px;margin:0 auto;padding:0 16px}
header.site{background:#fff;border-bottom:1px solid var(--line)}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:8px;padding:14px 16px}
.logo{font-weight:800;font-size:1.2rem;color:var(--text);text-decoration:none}
.logo span{color:var(--brand)}
nav a{margin-left:16px;text-decoration:none;color:var(--muted);font-weight:500}
nav a:hover{color:var(--brand)}
.hero{padding:48px 0 32px}
.hero h1{font-size:2rem;line-height:1.2;margin:0 0 12px}
.hero p{color:var(--muted);max-width:640px;margin:0 0 20px}
.btn{display:inline-block;background:var(--brand);color:#fff;padding:10px 18px;border-radius:8px;text-decoration:none;font-weight:600;border:0;cursor:pointer;font-size:1rem}
.btn:hover{background:var(--brand-d)}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:16px;margin:16px 0 40px}
.card{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:18px}
.card h3{margin:0 0 6px;font-size:1.05rem}
.card p{margin:0 0 10px;color:var(--muted);font-size:.95rem}
article{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:24px;margin:24px 0 40px}
article h1{margin-top:0;line-height:1.25}
article h2{margin-top:28px}
.note{background:#fff8e1;border:1px solid #ffe08a;border-radius:8px;padding:12px 14px;font-size:.93rem;margin:20px 0}
.crumbs{font-size:.88rem;color:var(--muted);margin-top:20px}
form.calc label{display:block;margin:12px 0 4px;font-weight:600;font-size:.95rem}
form.calc input,form.calc select{width:100%;padding:9px 10px;border:1px solid var(--line);border-radius:8px;font-size:1rem}
.row{display:grid;grid-template-columns:1fr 1fr;gap:12px}
@media(max-width:560px){.row{grid-template-columns:1fr}.hero h1{font-size:1.6rem}}
#sonuc{margin-top:20px}
#sonuc table{width:100%;border-collapse:collapse}
#sonuc td{padding:8px 4px;border-bottom:1px solid var(--line)}
#sonuc td:last-child{text-align:right;font-variant-numeric:tabular-nums}
#sonuc tr.toplam td{font-weight:800;font-size:1.1rem;border-bottom:0}
footer.site{border-top:1px solid var(--line);background:#fff;padding:20px 0;color:var(--muted);font-size:.9rem}