:root{--ink:#1f2937;--muted:#6b7280;--line:#e5e7eb;--bg:#ffffff;
--card:#f9fafb;--accent:#0d9488;--accent-dark:#0f766e;--radius:12px}
*{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}
.wrap{max-width:720px;margin:0 auto;padding:0 20px}
.site-header{border-bottom:1px solid var(--line);background:#fff}
.site-header .wrap{display:flex;align-items:center;justify-content:space-between;
padding-top:14px;padding-bottom:14px}
.brand{font-weight:700;font-size:1.1rem;color:var(--ink);text-decoration:none}
.topnav a{margin-left:18px;color:var(--muted);text-decoration:none;font-size:.95rem}
.topnav a:hover{color:var(--accent-dark)}
main{padding:40px 0 56px}
h1{font-size:1.9rem;line-height:1.25;margin:0 0 8px}
.lede{color:var(--muted);margin:0 0 24px}
.tool-card{background:var(--card);border:1px solid var(--line);border-radius:
var(--radius);padding:28px;margin-bottom:28px}
.field{margin-bottom:16px}
label{display:block;font-size:.85rem;font-weight:600;margin-bottom:6px}
input[type=number]{width:100%;padding:12px;border:1px solid var(--line);
border-radius:8px;font-size:1rem}
input[type=range]{width:100%}
.btn{background:var(--accent);color:#fff;border:0;border-radius:8px;
padding:12px 20px;font-size:1rem;font-weight:600;cursor:pointer;width:100%}
.btn:hover{background:var(--accent-dark)}
.result{margin-top:20px;background:#fff;border:1px solid var(--line);
border-radius:8px;padding:18px;display:none}
.result.show{display:block}
.result .big{font-size:2rem;font-weight:700;color:var(--accent-dark)}
.result .row{display:flex;justify-content:space-between;padding:6px 0;
border-bottom:1px dashed var(--line)}
.how h2{font-size:1.3rem;margin:32px 0 10px}
.how ol{padding-left:20px;color:var(--muted)}
.site-footer{border-top:1px solid var(--line);padding:24px 0;color:var(--muted);
font-size:.85rem}
.site-footer .wrap{display:flex;flex-wrap:wrap;gap:8px 24px;justify-content:space-between}
.site-footer a{color:var(--muted);text-decoration:none}
.site-footer a:hover{color:var(--accent-dark)}
.prose h1{font-size:1.7rem}
.prose p{color:var(--ink)}
select,input[type=text]{width:100%;padding:12px;border:1px solid var(--line);
border-radius:8px;font-size:1rem;background:#fff}
.hint{color:var(--muted);font-size:.9rem}
.btn-row{display:flex;gap:12px;flex-wrap:wrap}
.btn-row .btn{width:auto;flex:1;min-width:150px}
.btn.ghost{background:#fff;color:var(--accent-dark);border:1px solid var(--accent-dark)}
.btn.ghost:hover{background:#f0fdfa}
.btn.sm{width:auto;padding:8px 12px;font-size:.85rem;align-self:end}
#compare-result,#ladder-result{display:block}
.cd-row{display:grid;grid-template-columns:1fr 1fr;gap:4px 12px;border:1px solid var(--line);
border-radius:8px;padding:14px;margin-bottom:12px;background:#fff}
.cd-row .grow{grid-column:1/-1}
.term-pair{display:flex;gap:8px}
.term-pair input{flex:1}
.term-pair select{flex:1}
.table-scroll{overflow-x:auto}
table{width:100%;border-collapse:collapse;font-size:.9rem;min-width:520px}
caption{text-align:left;font-weight:600;margin-bottom:8px;color:var(--muted)}
th,td{text-align:left;padding:10px 8px;border-bottom:1px solid var(--line);
white-space:nowrap}
thead th{border-bottom:2px solid var(--line)}
th button{background:none;border:0;color:var(--accent-dark);font:inherit;
font-weight:700;cursor:pointer;padding:0}
tr.best{background:#f0fdfa}
tr.best th,tr.best td{font-weight:700}
.badge{display:inline-block;background:var(--accent);color:#fff;font-size:.7rem;
border-radius:999px;padding:2px 8px;margin-left:6px;font-weight:600}
.ladder-controls{display:flex;gap:12px;flex-wrap:wrap;align-items:flex-end}
.ladder-controls .field{flex:1;min-width:140px;margin-bottom:12px}
.ladder-controls .btn{width:auto;margin-bottom:12px}
.rung-label{font-size:1.1rem;font-weight:700;color:var(--accent-dark)}
.diagram{margin-top:16px}
.bar-row{display:flex;align-items:center;gap:10px;margin-bottom:8px}
.bar-label{width:44px;font-size:.85rem;color:var(--muted)}
.bar-track{flex:1;background:#eef2f7;border-radius:6px;height:22px;overflow:hidden}
.bar-fill{display:block;height:100%;background:var(--accent);border-radius:6px}
.bar-val{font-size:.85rem;font-weight:600;min-width:96px;text-align:right}
.disclaimer{background:#fffbeb;border:1px solid #fde68a;border-radius:8px;
padding:14px;font-size:.9rem}
@media(max-width:520px){h1{font-size:1.55rem}.tool-card{padding:20px}
th,td{padding:8px 6px;font-size:.82rem}}