:root {
  --bg: #0b0d18;
  --panel: rgba(8, 10, 22, 0.64);
  --card: #151a2e;
  --card-hover: #1c2340;
  --text: #f3f5ff;
  --muted: #9aa3c7;
  --accent: #00d7ff;
  --sung: #00d7ff;
  --unsung: #ffffff;
  --danger: #ff5c7a;
  --radius: 16px;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; background: var(--bg); color: var(--text); }
body { font: 16px/1.4 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; -webkit-tap-highlight-color: transparent; }
button, input, select { font: inherit; color: inherit; }
a { color: var(--accent); }

.btn {
  border: 0; border-radius: 12px; padding: 10px 16px; background: var(--card); cursor: pointer;
  display: inline-flex; align-items: center; gap: 8px; white-space: nowrap;
}
.btn:hover { background: var(--card-hover); }
.btn.primary { background: var(--accent); color: #001018; font-weight: 700; }
.btn.ghost { background: transparent; }
.btn.danger { color: var(--danger); }
.btn:disabled { opacity: .5; cursor: default; }

/* ---------- login / library ---------- */

.page { max-width: 880px; margin: 0 auto; padding: max(20px, env(safe-area-inset-top)) 16px 40px; }
.center { min-height: 100vh; display: grid; place-items: center; padding: 16px; }
.login { width: min(360px, 100%); background: var(--card); border-radius: var(--radius); padding: 28px; display: grid; gap: 14px; }
.login h1 { margin: 0; font-size: 24px; }
.field { width: 100%; padding: 12px 14px; border-radius: 12px; border: 1px solid #2a3150; background: #0e1224; }
.error { color: var(--danger); min-height: 1.2em; margin: 0; }
.muted { color: var(--muted); }

.topbar { display: flex; align-items: center; gap: 12px; margin-bottom: 18px; flex-wrap: wrap; }
.topbar h1 { margin: 0; font-size: 26px; flex: 1; }
.search { flex: 1 1 220px; }
.room-badge { background: #10283a; color: var(--accent); border-radius: 999px; padding: 6px 12px; font-size: 14px; }

.songs { display: grid; gap: 10px; }
.song { display: flex; align-items: center; gap: 14px; background: var(--card); border-radius: var(--radius); padding: 14px 16px; cursor: pointer; }
.song:hover { background: var(--card-hover); }
.song .title { font-weight: 650; flex: 1; overflow-wrap: anywhere; }
.song .info { color: var(--muted); font-size: 14px; white-space: nowrap; }
.empty { text-align: center; padding: 60px 10px; color: var(--muted); }

/* ---------- karaoke stage ---------- */

.stage { position: fixed; inset: 0; overflow: hidden; background: #05060c; user-select: none; }
.stage.idle { cursor: none; }
.bg-video { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; filter: brightness(.72) saturate(1.05); }
.bg-gradient {
  position: absolute; inset: -20%;
  background: linear-gradient(120deg, #1a1446, #0b3a5c, #3b1050, #08324a, #1a1446);
  background-size: 400% 400%;
  animation: drift 28s ease-in-out infinite;
}
@keyframes drift { 0%, 100% { background-position: 0% 50%; } 50% { background-position: 100% 50%; } }

.lyrics {
  position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%);
  width: min(94vw, 1500px); padding: clamp(12px, 2.6vh, 34px) clamp(14px, 3vw, 48px);
  background: var(--panel); border-radius: 22px;
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
  box-shadow: 0 10px 40px rgba(0, 0, 0, .35);
  transition: opacity .35s ease;
}
.lyrics.hidden { opacity: 0; }
.row {
  min-height: 1.3em; text-align: center; font-weight: 800; line-height: 1.28;
  font-size: clamp(22px, 4.6vw, 72px); letter-spacing: .01em;
  transition: opacity .2s ease; overflow-wrap: anywhere;
}
.row + .row { margin-top: .25em; }
.row.fade { opacity: 0; }
.row.title { color: var(--sung); }
.w {
  background: linear-gradient(90deg, var(--sung) calc(var(--p, 0) * 100%), var(--unsung) calc(var(--p, 0) * 100%));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.ear .row { font-size: clamp(20px, 6vw, 40px); }
.ear .lyrics { top: 42%; }

/* controls */
.controls {
  position: absolute; left: 0; right: 0; bottom: 0; padding: 14px max(16px, env(safe-area-inset-right)) max(14px, env(safe-area-inset-bottom)) max(16px, env(safe-area-inset-left));
  background: linear-gradient(transparent, rgba(0, 0, 0, .78) 45%);
  display: grid; gap: 10px; transition: opacity .3s ease;
}
.stage.idle .controls, .stage.idle .top-controls { opacity: 0; pointer-events: none; }
.top-controls {
  position: absolute; top: 0; left: 0; right: 0; display: flex; gap: 8px; align-items: center;
  padding: max(12px, env(safe-area-inset-top)) 16px 12px; background: linear-gradient(rgba(0, 0, 0, .65), transparent);
  transition: opacity .3s ease;
}
.top-controls .song-title { flex: 1; font-weight: 650; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.bar { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.bar .time { font-variant-numeric: tabular-nums; color: var(--muted); font-size: 14px; min-width: 92px; }
.seek { flex: 1 1 100%; width: 100%; accent-color: var(--accent); }
.slider { display: inline-flex; align-items: center; gap: 8px; font-size: 14px; color: var(--muted); }
.slider input { width: 120px; accent-color: var(--accent); }
.spacer { flex: 1; }
.play { width: 52px; height: 52px; border-radius: 50%; justify-content: center; font-size: 22px; padding: 0; }

.peers { font-size: 14px; color: var(--accent); }

/* tap-to-start and dialogs */
.overlay { position: absolute; inset: 0; display: grid; place-items: center; background: rgba(0, 0, 0, .55); z-index: 5; padding: 16px; }
.dialog { background: var(--card); border-radius: var(--radius); padding: 22px; width: min(420px, 100%); display: grid; gap: 14px; text-align: center; }
.dialog h2 { margin: 0; font-size: 20px; }
.dialog img { width: 240px; height: 240px; margin: 0 auto; background: #fff; border-radius: 12px; padding: 8px; }
.dialog .code { font-size: 28px; font-weight: 800; letter-spacing: .15em; }
.dialog .link { font-size: 13px; overflow-wrap: anywhere; }
.seg { display: inline-flex; background: #0e1224; border-radius: 12px; padding: 4px; gap: 4px; }
.seg button { border: 0; background: transparent; padding: 8px 14px; border-radius: 9px; cursor: pointer; }
.seg button.on { background: var(--accent); color: #001018; font-weight: 700; }

.ear-panel { position: absolute; left: 0; right: 0; bottom: 0; padding: 16px 16px max(16px, env(safe-area-inset-bottom)); display: grid; gap: 14px; background: linear-gradient(transparent, rgba(0, 0, 0, .8) 30%); }
.ear-list { max-height: 40vh; overflow: auto; display: grid; gap: 8px; }

/* output-delay profiles */
.offset { display: inline-flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.offset.full { display: grid; gap: 10px; justify-items: center; }
.offset-row { display: inline-flex; gap: 6px; align-items: center; flex-wrap: wrap; justify-content: center; }
.profile-select { width: auto; max-width: 240px; padding: 8px 10px; }
.offset.full .profile-select { max-width: 100%; width: 320px; }
.offset-value { font-variant-numeric: tabular-nums; min-width: 72px; text-align: center; font-weight: 700; }
.offset.full .offset-value { font-size: 20px; min-width: 84px; }
.btn.step { padding: 8px 12px; font-variant-numeric: tabular-nums; background: #0e1224; border: 1px solid #2a3150; }
.btn.step:hover { background: var(--card-hover); }
.offset.full .offset-row { flex-wrap: nowrap; }
.offset.full .btn.step { padding: 12px 0; width: 56px; justify-content: center; font-size: 17px; }
.dialog .btn { justify-content: center; }

/* calibration */
.calib { z-index: 6; background: rgba(0, 0, 0, .72); }
.calib .dialog { width: min(460px, 100%); }
.lamp { width: 120px; height: 120px; margin: 4px auto; border-radius: 50%; background: #1d2440; box-shadow: inset 0 0 0 4px #2a3150; }
.lamp.on { background: var(--accent); box-shadow: 0 0 40px var(--accent); }

@media (max-width: 560px) {
  .slider input { width: 90px; }
  .bar .time { min-width: auto; }
}