:root {
  --bg: #0b1020; --card: #141a2a; --text: #e7eefc; --muted: #93a1bb;
  --accent: #6b7280; --accent-2: #a1a1aa;
}
* { box-sizing: border-box; } html, body { margin:0; padding:0; background:var(--bg); color:var(--text); font-family: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif; }
header.brand { display:flex; gap:12px; align-items:center; padding:16px 20px 0; }
header.brand img { width:48px; height:48px; border-radius:8px; background:#0f1529; padding:6px; }
header.brand h1 { margin:0; font-size:1.2rem; }
header.brand p { margin:4px 0 0; color:var(--muted); }
main { padding: 12px 16px 24px; } .card { background: var(--card); border: 1px solid #1f2a44; border-radius: 14px; padding: 16px; margin-bottom: 16px; }
h2 { margin: 0 0 10px; font-size: 1.1rem; }
.grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; } @media (max-width: 680px) { .grid { grid-template-columns: 1fr; } }
label { display: grid; gap: 6px; font-size: 0.9rem; color: var(--muted); }
input[type=number] { width: 100%; padding: 10px 12px; border: 1px solid #2a3457; background: #0f1529; color: var(--text); border-radius: 10px; font-size: 1rem; }
button { padding: 10px 14px; border-radius: 10px; border: 1px solid #2a3457; background: #0f1529; color: var(--text); font-weight: 600; }
button.primary { background: linear-gradient(135deg, var(--accent), var(--accent-2)); border: none; }
button:active { transform: translateY(1px); }
.presets { display: flex; gap: 8px; flex-wrap: wrap; margin: 10px 0; }
.results { white-space: pre-wrap; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; background: #0f1529; border: 1px solid #2a3457; border-radius: 10px; padding: 12px; min-height: 130px; }
footer { text-align: right; padding: 0 16px 20px; color: var(--muted); }