:root {
  --bg: #0a0f0d; --surface: #121a16; --surface2: #1a2620; --border: #2a3d34;
  --text: #e8f5ee; --muted: #95b3a5; --accent: #34d399; --good: #34d399;
  --input-bg: #0a1210; --glow: #143028;
  --font: "Segoe UI", system-ui, -apple-system, sans-serif;
}
html[data-theme="light"] {
  --bg: #f3faf6; --surface: #ffffff; --surface2: #ecfdf5; --border: #d1fae5;
  --text: #064e3b; --muted: #047857; --accent: #059669; --good: #059669;
  --input-bg: #ffffff; --glow: #d1fae5;
}
* { box-sizing: border-box; }
body {
  margin: 0; font-family: var(--font); color: var(--text); line-height: 1.65; min-height: 100vh;
  background: radial-gradient(800px 400px at 0% 0%, var(--glow) 0%, transparent 50%), var(--bg);
}
a { color: #2dd4bf; }
html[data-theme="light"] a { color: #0d9488; }
.wrap { max-width: 720px; margin: 0 auto; padding: 24px 18px 64px; }
nav.top {
  display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 22px; padding-bottom: 14px;
  border-bottom: 1px solid var(--border);
}
nav.top a {
  color: var(--muted); text-decoration: none; padding: 6px 12px;
  border: 1px solid var(--border); border-radius: 999px; font-size: .88rem;
}
nav.top a.home {
  background: linear-gradient(135deg, #059669, #34d399); color: #042f1a; border: none; font-weight: 700;
}
html[data-theme="light"] nav.top a.home { color: #fff; }
.theme-btn {
  appearance: none; cursor: pointer; font: inherit; font-size: .88rem; font-weight: 600;
  color: var(--muted); background: var(--surface); border: 1px solid var(--border);
  padding: 6px 12px; border-radius: 999px;
}
.badge {
  display: inline-block; font-size: 11px; text-transform: uppercase; letter-spacing: .04em;
  color: var(--accent); background: rgba(52,211,153,.12); border: 1px solid rgba(52,211,153,.35);
  padding: 4px 10px; border-radius: 999px; margin-bottom: 12px;
}
h1 { font-size: clamp(1.5rem, 4vw, 2rem); margin: 0 0 12px; line-height: 1.25; }
.lede { color: var(--muted); font-size: 1.05rem; margin: 0 0 20px; }
.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: 14px;
  padding: 18px; margin: 18px 0;
}
label { display: block; font-size: .88rem; color: var(--muted); margin-bottom: 5px; }
.field { margin-bottom: 12px; }
input {
  width: 100%; background: var(--input-bg); border: 1px solid var(--border); color: var(--text);
  border-radius: 10px; padding: 11px 12px; font-size: 1rem;
}
.row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
@media (max-width: 520px) { .row2 { grid-template-columns: 1fr; } }
.big { font-size: 1.7rem; font-weight: 800; color: var(--good); margin: 10px 0 4px; }
.sub { color: var(--muted); font-size: .9rem; }
.btn {
  border: none; border-radius: 10px; padding: 11px 16px; font-weight: 700; cursor: pointer;
  background: linear-gradient(135deg, #059669, #34d399); color: #042f1a;
}
html[data-theme="light"] .btn { color: #fff; }
.presets { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 12px; }
.preset {
  border: 1px dashed var(--border); background: transparent; color: var(--muted);
  font-size: .78rem; padding: 6px 10px; border-radius: 8px; cursor: pointer; font-weight: 600;
}
.metrics { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-top: 12px; }
.metric { background: var(--surface2); border: 1px solid var(--border); border-radius: 10px; padding: 10px; }
.metric .k { font-size: .7rem; text-transform: uppercase; color: var(--muted); }
.metric .v { font-weight: 700; margin-top: 3px; }
article h2 { font-size: 1.2rem; margin: 28px 0 10px; }
article p, article li { color: var(--muted); }
article ul, article ol { padding-left: 1.2rem; }
details {
  background: var(--surface); border: 1px solid var(--border); border-radius: 10px;
  padding: 12px 14px; margin-bottom: 8px;
}
summary { cursor: pointer; font-weight: 650; color: var(--text); }
details p { margin: 10px 0 0; }
.cta {
  display: inline-block; margin: 6px 8px 6px 0; padding: 10px 14px;
  background: var(--surface); border: 1px solid var(--border); border-radius: 10px;
  text-decoration: none; color: var(--text); font-weight: 600;
}
footer {
  margin-top: 36px; padding-top: 16px; border-top: 1px solid var(--border);
  color: var(--muted); font-size: .85rem;
}