:root {
  --bg: #0b1020;
  --card: rgba(255, 255, 255, 0.04);
  --line: rgba(255, 255, 255, 0.10);
  --text: #e8edf7;
  --muted: #8b95ad;
  --accent: #4f8cff;
  --accent2: #22d3a5;
  --danger: #ff5d6c;
  --radius: 14px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { min-height: 100%; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background:
    radial-gradient(1000px 500px at 15% -10%, rgba(79, 140, 255, 0.18), transparent 60%),
    radial-gradient(800px 500px at 90% 110%, rgba(34, 211, 165, 0.12), transparent 60%),
    var(--bg);
  color: var(--text);
}

.app {
  max-width: 560px;
  margin: 0 auto;
  padding: 28px 16px 40px;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

header.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}
.brand { display: flex; align-items: center; gap: 12px; }
.logo { font-size: 30px; }
h1 { font-size: 22px; letter-spacing: 2px; }
.tagline { font-size: 12px; color: var(--muted); margin-top: 2px; }
.badge {
  background: rgba(34, 211, 165, 0.12);
  color: var(--accent2);
  border: 1px solid rgba(34, 211, 165, 0.35);
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 12px;
  white-space: nowrap;
}

.mode-strip {
  text-align: center;
  font-size: 12px;
  color: var(--muted);
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  margin-bottom: 22px;
}
.mode-strip.on {
  color: var(--accent2);
  border-color: rgba(34, 211, 165, 0.35);
  background: rgba(34, 211, 165, 0.07);
}
.mode-strip.off {
  color: #ffc861;
  border-color: rgba(255, 200, 97, 0.35);
  background: rgba(255, 200, 97, 0.06);
}

main { flex: 1; display: flex; align-items: center; justify-content: center; }
.screen { display: none; width: 100%; }
.screen.active { display: block; animation: fade 0.25s ease; }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 24px;
  backdrop-filter: blur(10px);
}
.card.center { text-align: center; }
.card h2 { font-size: 18px; margin-bottom: 20px; }

.btn {
  display: block;
  width: 100%;
  padding: 12px 16px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.06);
  color: var(--text);
  font-size: 15px;
  cursor: pointer;
  transition: transform 0.1s ease, background 0.15s ease, filter 0.15s ease;
}
.btn:hover { background: rgba(255, 255, 255, 0.10); }
.btn:active { transform: scale(0.98); }
.btn.primary { background: linear-gradient(135deg, #4f8cff, #3b6fe0); border-color: transparent; font-weight: 600; }
.btn.primary:hover { filter: brightness(1.08); }
.btn.ghost { background: transparent; }
.btn.danger { background: linear-gradient(135deg, #ff5d6c, #e04050); border-color: transparent; }
.btn.danger-ghost { background: transparent; color: var(--danger); border-color: rgba(255, 93, 108, 0.35); }

.divider { display: flex; align-items: center; gap: 10px; margin: 18px 0; color: var(--muted); font-size: 12px; }
.divider::before, .divider::after { content: ""; flex: 1; height: 1px; background: var(--line); }

.join-row { display: flex; gap: 10px; }
.code-input {
  flex: 1;
  padding: 12px 14px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: rgba(0, 0, 0, 0.25);
  color: var(--text);
  font-size: 16px;
  letter-spacing: 3px;
  text-transform: uppercase;
  text-align: center;
  outline: none;
  min-width: 0;
}
.code-input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(79, 140, 255, 0.15); }
.join-row .btn { width: auto; }

.error { color: var(--danger); font-size: 13px; margin-top: 14px; }
.hidden { display: none !important; }
.hint { color: var(--muted); font-size: 13px; margin-top: 12px; line-height: 1.6; }

.room-code {
  font-size: 34px;
  letter-spacing: 8px;
  font-weight: 700;
  margin: 18px 0 6px;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}
.status { color: var(--muted); font-size: 13px; margin: 14px 0 18px; min-height: 18px; }
.center .btn { margin-top: 8px; }

.call-status-row { display: flex; align-items: center; justify-content: center; gap: 10px; }
.call-status { font-size: 15px; }
.timer { font-size: 13px; color: var(--muted); font-variant-numeric: tabular-nums; }
.pulse {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent2);
  animation: pulse 1.4s infinite;
}
.pulse.off { animation: none; background: var(--muted); }
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(34, 211, 165, 0.5); }
  50% { box-shadow: 0 0 0 8px rgba(34, 211, 165, 0); }
}

.verify-box {
  margin: 26px 0 6px;
  padding: 18px;
  border: 1px dashed rgba(79, 140, 255, 0.4);
  border-radius: 12px;
  background: rgba(79, 140, 255, 0.06);
}
.verify-label { font-size: 12px; color: var(--muted); }
.verify-code {
  font-size: 30px;
  letter-spacing: 10px;
  font-weight: 700;
  margin-top: 8px;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

.controls { display: flex; gap: 12px; margin-top: 24px; }
.controls .btn { flex: 1; }

.foot { margin-top: 30px; color: var(--muted); font-size: 12px; line-height: 1.8; text-align: center; }

.debug { margin-top: 18px; color: var(--muted); font-size: 12px; }
.debug summary { cursor: pointer; user-select: none; }
#log {
  margin-top: 8px;
  max-height: 180px;
  overflow: auto;
  font-family: Consolas, "Courier New", monospace;
  font-size: 11px;
  line-height: 1.7;
  white-space: pre-wrap;
  word-break: break-all;
}