:root {
  --bg: #0f172a;
  --card: #111827;
  --text: #e5e7eb;
  --muted: #94a3b8;
  --accent: #22c55e;
  --error: #ef4444;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0; font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, Arial, sans-serif;
  background: radial-gradient(1000px 600px at 10% 10%, #1f2937 0%, var(--bg) 50%);
  color: var(--text);
}

.container {
  max-width: 760px; margin: 0 auto; padding: 32px 20px; display: flex; flex-direction: column; gap: 16px;
}
header h1 { margin: 0 0 4px; font-size: 28px; }
header p { margin: 0; color: var(--muted); }

.card {
  background: linear-gradient(180deg, var(--card), #0b1220 100%);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 12px; padding: 20px; display: flex; flex-direction: column; gap: 14px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.25);
}

.btn {
  background: linear-gradient(90deg, #10b981, var(--accent));
  color: #031b0c; border: none; border-radius: 10px; padding: 12px 16px; font-weight: 700; cursor: pointer;
  transition: transform 0.06s ease, box-shadow 0.2s ease; box-shadow: 0 10px 18px rgba(16,185,129,0.25);
}
.btn:disabled { opacity: 0.7; cursor: not-allowed; filter: grayscale(0.2); }
.btn:hover:not(:disabled) { transform: translateY(-1px); }

.field { display: flex; flex-direction: column; gap: 6px; }
.field label { color: var(--muted); font-size: 14px; }
.value-row { display: flex; align-items: center; gap: 10px; }
code { background: rgba(255,255,255,0.06); padding: 8px 10px; border-radius: 8px; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }

.copy { padding: 8px 10px; border-radius: 8px; border: 1px solid rgba(255,255,255,0.08); background: rgba(255,255,255,0.06); color: var(--text); cursor: pointer; }
.copy:hover { background: rgba(255,255,255,0.12); }

.hint { color: var(--muted); font-size: 13px; margin-top: 6px; }
.error { color: #fff; background: linear-gradient(180deg, rgba(239,68,68,0.25), rgba(239,68,68,0.15)); border: 1px solid rgba(239,68,68,0.35); padding: 10px 12px; border-radius: 8px; }
.hidden { display: none; }

footer { color: var(--muted); font-size: 13px; }
footer a { color: var(--text); }