:root {
  color-scheme: light dark;
  --bg: #0f1115;
  --card: #1a1d24;
  --fg: #e8eaed;
  --muted: #9aa0a6;
  --accent: #4f8cff;
  --warn: #ffcc66;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Noto Sans KR", sans-serif;
  background: var(--bg);
  color: var(--fg);
}
.wrap { max-width: 640px; margin: 0 auto; padding: 16px; }
header h1 { margin: 0; font-size: 22px; }
.sub { margin: 2px 0 0; color: var(--muted); }
.muted { color: var(--muted); font-size: 13px; }
.fine { color: var(--muted); font-size: 12px; }
.warn { color: var(--warn); font-size: 13px; }
.card {
  background: var(--card);
  border-radius: 12px;
  padding: 16px;
  margin-top: 14px;
}
.card h2 { margin: 0 0 10px; font-size: 15px; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; }
label { display: block; margin: 10px 0 4px; font-size: 13px; color: var(--muted); }
input {
  width: 100%;
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid #333842;
  background: #0d0f13;
  color: var(--fg);
  font-size: 15px;
}
.status { font-size: 15px; margin: 8px 0; min-height: 20px; }
.diag {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 12.5px;
  line-height: 1.7;
  background: #0d0f13;
  border: 1px solid #333842;
  border-radius: 8px;
  padding: 10px 12px;
  margin: 8px 0 12px;
  white-space: pre-wrap;
  word-break: break-word;
}
#btn-reopen { background: #2c3140; }
.row { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 12px; }
button {
  padding: 10px 14px;
  border-radius: 8px;
  border: none;
  background: var(--accent);
  color: #fff;
  font-size: 14px;
  cursor: pointer;
}
button:active { filter: brightness(.9); }
#btn-clear { background: #444b57; }
#btn-check, #btn-paired { background: #2c3140; }