:root{
  --green:#2e6b34;--green-dark:#1f4a24;--green-light:#e8f2e9;
  --ink:#1c2320;--muted:#5b6660;--bg:#fafaf7;--card:#ffffff;--line:#e2e5df;
  --accent:#c47b2a;
}
*{box-sizing:border-box}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;color:var(--ink);background:var(--bg);line-height:1.6;font-size:17px}
.wrap{max-width:820px;margin:0 auto;padding:0 20px}
a{color:var(--green)}
h1{font-size:1.9rem;line-height:1.25;margin:.7em 0 .4em}
h2{font-size:1.35rem;margin-top:1.8em}
h3{font-size:1.1rem;margin-top:1.6em}
.site-header{background:var(--green-dark);color:#fff}
.site-header .wrap{display:flex;justify-content:space-between;align-items:center;padding:14px 20px}
.logo{color:#fff;text-decoration:none;font-weight:700;font-size:1.15rem}
.logo span{color:#a8d5ab}
.site-header nav a{color:#d8e8d9;text-decoration:none;font-size:.95rem}
.site-header nav a:hover{color:#fff}
.crumbs{font-size:.85rem;color:var(--muted);margin-top:14px}
.crumbs a{color:var(--muted)}
.intro{color:var(--muted);font-size:1.05rem}
.calc-card{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:22px;margin:22px 0;box-shadow:0 2px 8px rgba(0,0,0,.04)}
.field{margin-bottom:14px}
.field label{display:block;font-weight:600;font-size:.92rem;margin-bottom:4px}
.field .hint{font-weight:400;color:var(--muted)}
.row{display:flex;gap:10px;flex-wrap:wrap}
.row .field{flex:1;min-width:130px}
input[type=number],select{width:100%;padding:10px 12px;font-size:1rem;border:1px solid #c6ccc4;border-radius:8px;background:#fff;color:var(--ink)}
input[type=number]:focus,select:focus{outline:2px solid var(--green);border-color:var(--green)}
.unit-pair{display:flex;gap:8px}
.unit-pair input{flex:2}
.unit-pair select{flex:1;min-width:88px}
.results{margin-top:18px;background:var(--green-light);border-radius:10px;padding:16px 18px}
.results-h{margin:.1em 0 .4em;font-size:1.1rem}
.res-big{font-size:1.5rem;font-weight:700;color:var(--green-dark)}
.res-line{margin:.3em 0}
.res-note{font-size:.88rem;color:var(--muted)}
table{border-collapse:collapse;width:100%;margin:1em 0;font-size:.95rem}
th,td{border:1px solid var(--line);padding:8px 10px;text-align:left}
th{background:var(--green-light)}
.faq details{border:1px solid var(--line);border-radius:8px;margin:8px 0;background:var(--card)}
.faq summary{padding:12px 14px;font-weight:600;cursor:pointer}
.faq .faq-a{padding:0 14px 12px}
.related ul{padding-left:1.2em}
.related li{margin:.4em 0}
.hero{padding:2.2em 0 .5em}
.hero h1{font-size:2.1rem}
.hero p{font-size:1.1rem;color:var(--muted);max-width:620px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:12px;margin:12px 0 4px}
.card{display:flex;flex-direction:column;gap:4px;background:var(--card);border:1px solid var(--line);border-radius:10px;padding:16px;text-decoration:none;color:var(--ink);transition:border-color .15s,transform .15s}
.card:hover{border-color:var(--green);transform:translateY(-2px)}
.card-emoji{font-size:1.5rem}
.card span:last-child{font-size:.88rem;color:var(--muted)}
.about p{max-width:680px}
.site-footer{margin-top:3em;background:#eef1ec;border-top:1px solid var(--line);font-size:.88rem;color:var(--muted)}
.site-footer .wrap{padding:20px}
button.calc-btn{background:var(--green);color:#fff;border:0;border-radius:8px;padding:12px 22px;font-size:1.05rem;font-weight:600;cursor:pointer;width:100%}
button.calc-btn:hover{background:var(--green-dark)}
@media(max-width:520px){h1{font-size:1.5rem}.hero h1{font-size:1.65rem}}