:root{
  --bg:#0d1017; --card:#151a24; --line:#232b3b; --text:#e9edf5;
  --muted:#98a2b8; --accent:#4f8cff; --good:#34d399; --radius:14px;
}
*{box-sizing:border-box;margin:0;padding:0}
body{background:var(--bg);color:var(--text);font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;line-height:1.65}
.wrap{max-width:880px;margin:0 auto;padding:0 20px}
.topbar{border-bottom:1px solid var(--line);position:sticky;top:0;background:rgba(13,16,23,.94);backdrop-filter:blur(8px);z-index:10}
.nav{display:flex;align-items:center;justify-content:space-between;padding:14px 20px}
.logo{font-weight:800;font-size:1.1rem;color:var(--text);text-decoration:none}
.logo span{color:var(--accent)}
.links{display:flex;gap:18px}
.links a{color:var(--muted);text-decoration:none;font-size:.92rem}
.links a:hover{color:var(--text)}
main{padding:28px 20px 60px}
.hero{margin-bottom:22px}
.hero h1{font-size:2rem;line-height:1.25;margin-bottom:10px}
.lead{color:var(--muted);font-size:1.05rem;max-width:680px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px;margin:20px 0}
.fields{display:flex;gap:14px;flex-wrap:wrap;margin-bottom:16px}
.field{display:flex;flex-direction:column;gap:6px;flex:1;min-width:140px;font-size:.85rem;color:var(--muted)}
.field input,.field select{background:#0b0e14;border:1px solid var(--line);color:var(--text);border-radius:9px;padding:10px 12px;font-size:1rem}
.opt{font-weight:400;opacity:.7}
.actions{display:flex;gap:12px;margin-bottom:16px}
.btn{border:none;border-radius:10px;padding:12px 26px;font-size:1rem;font-weight:700;cursor:pointer}
.btn.primary{background:var(--accent);color:#fff}
.btn.primary:hover{filter:brightness(1.08)}
.btn.primary:disabled{opacity:.45;cursor:not-allowed}
.btn.ghost{background:#202839;color:var(--text)}
.pad{border:2px dashed var(--line);border-radius:12px;min-height:200px;display:flex;align-items:center;justify-content:center;text-align:center;cursor:crosshair;user-select:none;padding:20px;color:var(--muted);outline:none}
.pad.live{border-color:var(--good);background:rgba(52,211,153,.05);color:var(--text)}
.pad p strong{color:var(--good)}
.result{margin-top:16px;font-size:1.1rem}
.dpi-line strong{font-size:1.9rem;color:var(--good)}
.dev,.median{color:var(--muted);font-size:.95rem;margin-top:4px}
.median strong{color:var(--text)}
.runs{margin-top:14px;overflow-x:auto}
.runs table{width:100%;border-collapse:collapse;font-size:.88rem}
.runs th,.runs td{border:1px solid var(--line);padding:7px 10px;text-align:center}
.runs th{background:#1a2130}
.runs td strong{color:var(--good)}
.note{margin-top:12px;font-size:.82rem;color:var(--muted)}
h2{font-size:1.4rem;margin:34px 0 10px}
.steps{margin:12px 0 12px 22px}
.steps li{margin:8px 0}
.formula{background:#0b0e14;border:1px solid var(--line);border-radius:10px;padding:12px 16px;margin:12px 0;display:inline-block}
.tips{margin:12px 0 12px 22px}
.tips li{margin:8px 0}
details{background:var(--card);border:1px solid var(--line);border-radius:10px;margin-bottom:10px;padding:13px 16px}
summary{cursor:pointer;font-weight:600}
details p{margin-top:8px;color:var(--muted);font-size:.95rem}
footer{border-top:1px solid var(--line);padding:22px 0;color:var(--muted);font-size:.85rem;text-align:center}
@media(max-width:560px){.hero h1{font-size:1.6rem}.card{padding:18px}.btn{flex:1}}