:root{
  color-scheme: light;
  --page:#faf7f0; --page-2:#f1ecdd; --surface:#fffdf8; --ink:#1f1d17; --ink-2:#5b564a; --muted:#8f887a;
  --grid:#e8e2d3; --axis:#cfc7b4; --border:rgba(60,50,20,.12);
  --series:#1e7a45; --series-2:#166536; --good:#1e7a45; --good-text:#14603a; --warn:#b9860f;
}
@media (prefers-color-scheme: dark){
  :root:where(:not([data-theme="light"])){
    color-scheme: dark;
    --page:#14120d; --page-2:#1c1913; --surface:#201c15; --ink:#f5f1e6; --ink-2:#c9c2b0; --muted:#948c7b;
    --grid:#322d23; --axis:#453f31; --border:rgba(255,240,200,.12);
    --series:#3aa967; --series-2:#2f9159; --good:#3aa967; --good-text:#4cbb7a; --warn:#d9a52e;
  }
}
:root[data-theme="dark"]{
  color-scheme: dark;
  --page:#14120d; --page-2:#1c1913; --surface:#201c15; --ink:#f5f1e6; --ink-2:#c9c2b0; --muted:#948c7b;
  --grid:#322d23; --axis:#453f31; --border:rgba(255,240,200,.12);
  --series:#3aa967; --series-2:#2f9159; --good:#3aa967; --good-text:#4cbb7a; --warn:#d9a52e;
}
*{box-sizing:border-box;margin:0}
body{font:16px/1.65 system-ui,-apple-system,"Segoe UI",sans-serif;color:var(--ink);
  background:linear-gradient(180deg,var(--page) 0%,var(--page-2) 100%);background-attachment:fixed;min-height:100vh}
.wrap{max-width:880px;margin:0 auto;padding:32px 24px 96px}
header{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:8px 0 56px;flex-wrap:wrap}
.brand{font-weight:700;letter-spacing:-.01em;text-decoration:none;color:var(--ink);font-size:17px}
.brand em{color:var(--series);font-style:normal}
nav{display:flex;gap:4px;align-items:center;flex-wrap:wrap}
nav a{color:var(--ink-2);text-decoration:none;font-size:14.5px;padding:5px 11px;border-radius:8px}
nav a:hover{background:var(--surface)}
nav a.active{color:var(--ink);font-weight:650}
nav a.cta{background:linear-gradient(135deg,var(--series),var(--series-2));color:#fff;font-weight:650}
#themeBtn{background:none;border:1px solid var(--border);border-radius:8px;color:var(--ink-2);padding:4px 10px;cursor:pointer;font-size:14px}
h1{font-size:clamp(28px,5vw,42px);line-height:1.18;letter-spacing:-.02em;margin-bottom:20px}
.lede{font-size:18px;color:var(--ink-2);max-width:60ch;margin-bottom:28px}
h2{font-size:22px;margin:64px 0 16px;letter-spacing:-.01em}
h3{font-size:16px;margin:20px 0 6px}
p{margin:14px 0;max-width:68ch}
.card{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:24px;margin:20px 0}
.btn{display:inline-block;background:linear-gradient(135deg,var(--series),var(--series-2));color:#fff;font-weight:650;text-decoration:none;padding:11px 22px;border-radius:10px;margin:18px 12px 0 0}
.btn.ghost{background:none;color:var(--series);border:1px solid var(--border)}
label{display:block;font-size:13px;color:var(--ink-2);margin:10px 0 3px}
select,input{width:100%;padding:8px 10px;font:inherit;color:var(--ink);background:var(--page);border:1px solid var(--border);border-radius:8px}
.grid2{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:0 16px}
.grid3{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:16px}
.grid4{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:0 16px}
details.adv{margin-top:14px}
details.adv summary{cursor:pointer;color:var(--ink-2);font-size:14px}
table{width:100%;border-collapse:collapse;font-size:15px;margin-top:8px}
th{color:var(--muted);font-weight:600;text-align:right;font-size:12.5px;text-transform:uppercase;letter-spacing:.04em;padding:8px 10px;border-bottom:1px solid var(--grid)}
th:first-child,td:first-child{text-align:left}
td{padding:10px;text-align:right;border-bottom:1px solid var(--grid);font-variant-numeric:tabular-nums}
tr.win td{font-weight:650}
.badge{display:inline-flex;align-items:center;gap:5px;font-size:12.5px;font-weight:650;color:var(--good-text)}
.badge svg{width:14px;height:14px}
.why{border-left:3px solid var(--series);padding:2px 0 2px 14px;margin:16px 0;color:var(--ink-2)}
.why strong{color:var(--ink)}
.note{font-size:13.5px;color:var(--muted)}
.chartbox{margin-top:18px}
.charttitle{font-size:14px;color:var(--ink-2);margin-bottom:6px}
svg.chart text{font:11.5px system-ui,-apple-system,"Segoe UI",sans-serif;fill:var(--muted)}
.tip{position:absolute;pointer-events:none;background:var(--surface);border:1px solid var(--border);border-radius:8px;padding:6px 10px;font-size:13px;box-shadow:0 2px 8px rgba(0,0,0,.12);display:none;white-space:nowrap}
.formula{background:var(--surface);border:1px solid var(--border);border-radius:8px;padding:10px 14px;font-family:ui-monospace,Menlo,monospace;font-size:13.5px;overflow-x:auto;margin:10px 0;color:var(--ink-2)}
footer{margin-top:96px;padding-top:24px;border-top:1px solid var(--grid);font-size:13.5px;color:var(--muted)}
a{color:var(--series)}
ul{margin:8px 0 8px 22px;max-width:66ch}
li{margin:4px 0}
.caveat{border:1px solid var(--warn);border-radius:12px;padding:20px 24px;margin:32px 0;background:var(--surface)}
.caveat h3{margin-top:0}

.form-status{font-size:14px;margin-top:6px;min-height:1.4em;color:var(--muted)}
.form-status.ok{color:var(--good-text)}
.form-status.err{color:#c0392b}
form .btn{border:none;cursor:pointer;font:inherit}