:root {
  --bg: #101014;
  --panel: #1a1a21;
  --text: #f2f2f5;
  --muted: #9a9aa5;
  --accent: #e53935;
  --accent-dark: #b71c1c;
  --ok: #43a047;
  --warn: #fbc02d;
  --err: #ef5350;
  --radius: 14px;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  display: flex;
  min-height: 100vh;
  align-items: center;
  justify-content: center;
  padding: 16px;
}
.card {
  background: var(--panel);
  border-radius: var(--radius);
  padding: 28px 24px;
  width: 100%;
  max-width: 420px;
  box-shadow: 0 12px 40px rgba(0, 0, 0, .45);
}
.brand { display: flex; align-items: center; gap: 10px; margin-bottom: 18px; }
.brand .logo {
  width: 34px; height: 34px; border-radius: 9px;
  background: var(--accent);
  display: flex; align-items: center; justify-content: center;
  font-size: 19px;
}
.brand h1 { font-size: 19px; margin: 0; font-weight: 700; }
h2 { font-size: 16px; margin: 0 0 6px; }
p { color: var(--muted); font-size: 14px; line-height: 1.5; margin: 0 0 14px; }
label { display: block; font-size: 12px; color: var(--muted); margin: 12px 0 5px; }
input, select {
  width: 100%;
  padding: 11px 12px;
  border-radius: 9px;
  border: 1px solid #33333d;
  background: #0d0d11;
  color: var(--text);
  font-size: 15px;
}
input:focus { outline: 2px solid var(--accent); border-color: transparent; }
.code-input { text-align: center; letter-spacing: .35em; font-size: 22px; text-transform: uppercase; }
button {
  width: 100%;
  margin-top: 16px;
  padding: 12px;
  border: 0;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
}
button:hover { background: var(--accent-dark); }
button.secondary { background: #2a2a33; }
button.secondary:hover { background: #34343f; }
button:disabled { opacity: .5; cursor: default; }
.row { display: flex; gap: 10px; }
.row button { flex: 1; }
.msg { margin-top: 14px; font-size: 14px; border-radius: 9px; padding: 10px 12px; display: none; }
.msg.err { display: block; background: rgba(239, 83, 80, .12); color: var(--err); }
.msg.ok { display: block; background: rgba(67, 160, 71, .14); color: var(--ok); }
.msg.info { display: block; background: rgba(251, 192, 45, .1); color: var(--warn); }
.device-box {
  background: #0d0d11;
  border: 1px solid #33333d;
  border-radius: 10px;
  padding: 14px;
  margin: 12px 0;
  font-size: 14px;
}
.device-box .name { font-weight: 700; font-size: 16px; }
.device-box .meta { color: var(--muted); font-size: 12px; margin-top: 4px; }
.big-tick { font-size: 52px; text-align: center; margin: 10px 0 4px; }
.hidden { display: none !important; }
.foot { margin-top: 18px; text-align: center; font-size: 12px; color: var(--muted); }
.seg { display: flex; background: #0d0d11; border: 1px solid #33333d; border-radius: 999px; padding: 3px; margin-top: 4px; }
.seg button { margin: 0; padding: 8px; border-radius: 999px; background: transparent; color: var(--muted); font-size: 13px; }
.seg button.active { background: var(--accent); color: #fff; }