:root {
  --bg: #0b0e14;
  --card: #151a23;
  --fg: #e6e9ef;
  --muted: #8b94a7;
  --accent: #3ddc97;
  --accent-2: #1f6f53;
  --border: #232a36;
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body {
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  display: flex;
  min-height: 100%;
}
.app { margin: auto; width: 100%; max-width: 420px; padding: 24px; }
.hd h1 { margin: 0 0 4px; font-size: 22px; letter-spacing: 0.3px; }
.sub { margin: 0; color: var(--muted); font-size: 13px; }
.card {
  margin-top: 24px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 20px;
}
.card h2 { margin: 0 0 4px; font-size: 16px; }
.hint { margin: 0 0 16px; color: var(--muted); font-size: 13px; }
.scale { display: flex; gap: 8px; }
.dot {
  flex: 1;
  aspect-ratio: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #0e131b;
  color: var(--fg);
  cursor: pointer;
  transition: transform 0.08s ease, background 0.15s ease, border-color 0.15s ease;
}
.dot .num { font-size: 18px; font-weight: 600; line-height: 1; }
.dot .lbl { font-size: 10px; font-weight: 500; color: var(--muted); line-height: 1; text-align: center; }
.dot:hover { border-color: var(--accent-2); }
.dot:active { transform: scale(0.94); }
.dot.sel { background: var(--accent); color: #06231a; border-color: var(--accent); }
.dot.sel .lbl { color: #06231a; }
.dot:disabled { opacity: 0.5; cursor: default; }
.status { margin: 16px 0 0; min-height: 20px; color: var(--muted); font-size: 14px; }
.status.ok { color: var(--accent); }
.status.err { color: #ff6b6b; }
.ft { margin-top: 18px; text-align: center; color: var(--muted); font-size: 12px; }