:root {
  --bg-0:#08070f;
  --bg-1:#100e1c;
  --bg-2:#181428;
  --txt:#f3f2fb;
  --muted:#a3a0c0;
  --accent:#7b8cff;        /* indigo */
  --accent-2:#a674ff;      /* violet */
  --accent-ink:#0b0a1a;    /* dark text on accent */
  --danger:#fb6a6a;
  --ok:#4ade80;
}

* { margin:0; padding:0; box-sizing:border-box; -webkit-tap-highlight-color:transparent; }

html, body {
  height:100%;
  font-family:-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background:var(--bg-0);
  color:var(--txt);
  overflow:hidden;
}

/* ── Start screen ───────────────────────────────────────────────────────── */
#start-screen {
  display:flex;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  min-height:100dvh;
  overflow-y:auto;
  padding:40px 28px;
  text-align:center;
  gap:16px;
  background:
    radial-gradient(120% 80% at 50% -10%, rgba(123,140,255,0.18) 0%, rgba(123,140,255,0) 55%),
    radial-gradient(120% 90% at 50% 110%, rgba(166,116,255,0.14) 0%, rgba(166,116,255,0) 50%),
    linear-gradient(180deg, var(--bg-1) 0%, var(--bg-0) 100%);
}
#start-screen h1 {
  font-size:2.3rem;
  font-weight:800;
  letter-spacing:-0.02em;
  background:linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 100%);
  -webkit-background-clip:text;
  background-clip:text;
  -webkit-text-fill-color:transparent;
}
#start-screen .sub  { font-size:0.98rem; color:var(--muted); line-height:1.55; max-width:330px; }
#start-screen .note { font-size:0.78rem; color:#5f6b80; margin-top:4px; }

/* start-page info points */
.tips {
  list-style:none;
  display:flex; flex-direction:column; gap:11px;
  max-width:350px; width:100%;
  text-align:left;
  margin:2px 0;
}
.tips li {
  display:flex; gap:12px; align-items:flex-start;
  background:rgba(19,28,46,0.55);
  border:1px solid rgba(255,255,255,0.07);
  border-radius:14px;
  padding:12px 14px;
}
.tips .ti { font-size:1.3rem; line-height:1.3; flex-shrink:0; }
.tips b   { display:block; color:#fff; font-size:0.9rem; margin-bottom:2px; }
.tips span:not(.ti) { color:var(--muted); font-size:0.8rem; line-height:1.4; }
#start-btn {
  margin-top:6px;
  background:linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 100%);
  color:var(--accent-ink);
  border:none;
  border-radius:999px;
  padding:16px 54px;
  font-size:1.08rem;
  font-weight:800;
  letter-spacing:0.01em;
  box-shadow:0 10px 30px rgba(123,140,255,0.35);
  transition:transform 0.12s, box-shadow 0.12s;
}
#start-btn:active { transform:scale(0.96); box-shadow:0 6px 18px rgba(123,140,255,0.3); }

/* ── Not supported ──────────────────────────────────────────────────────── */
#not-supported {
  display:none;
  height:100dvh;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  padding:32px;
  text-align:center;
  gap:14px;
  background:linear-gradient(180deg, var(--bg-1) 0%, var(--bg-0) 100%);
}
#not-supported h2 { font-size:1.4rem; color:#fb7185; }
#not-supported p  { color:var(--muted); line-height:1.5; max-width:340px; }

/* ── AR overlay ─────────────────────────────────────────────────────────── */
#ar-overlay { display:none; position:fixed; inset:0; }
#canvas     { display:none; position:fixed; inset:0; width:100%; height:100%; }

#line-svg { position:fixed; inset:0; width:100%; height:100%; pointer-events:none; z-index:12; }
#line {
  stroke:var(--accent); stroke-width:3.5; stroke-linecap:round;
  filter:drop-shadow(0 0 6px rgba(123,140,255,0.85));
  display:none;
}

/* corner markers */
.marker {
  position:absolute;
  width:26px; height:26px;
  border:3px solid var(--accent);
  background:rgba(123,140,255,0.22);
  border-radius:50%;
  transform:translate(-50%, -50%);
  box-shadow:0 0 12px rgba(123,140,255,0.7);
  pointer-events:none;
  z-index:13;
  display:none;
}

#dist-pill {
  position:absolute;
  transform:translate(-50%, -50%);
  background:linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 100%);
  color:var(--accent-ink);
  font-weight:800;
  font-size:0.95rem;
  border-radius:999px;
  padding:5px 14px;
  pointer-events:none;
  z-index:14;
  display:none;
  box-shadow:0 4px 14px rgba(123,140,255,0.4);
}

/* depth status badge (top-right) */
#mode-badge {
  position:fixed;
  top:18px; right:16px;
  display:flex; align-items:center; gap:7px;
  background:rgba(13,19,32,0.66);
  backdrop-filter:blur(10px);
  border:1px solid rgba(255,255,255,0.08);
  padding:6px 12px;
  border-radius:999px;
  font-size:0.72rem;
  font-weight:800;
  letter-spacing:0.05em;
  z-index:15;
}
#mode-dot { width:8px; height:8px; border-radius:50%; background:#64748b; }
#mode-badge.on  #mode-dot { background:var(--ok); box-shadow:0 0 8px var(--ok); }
#mode-badge.off #mode-dot { background:#64748b; }
#mode-badge.on  { color:var(--ok); }
#mode-badge.off { color:#cbd5e1; }

/* live source readout (top-left) */
#hud {
  position:fixed;
  top:18px; left:16px;
  background:rgba(13,19,32,0.66);
  backdrop-filter:blur(10px);
  border:1px solid rgba(255,255,255,0.08);
  padding:6px 12px;
  border-radius:999px;
  font-size:0.72rem;
  font-weight:700;
  font-variant-numeric:tabular-nums;
  z-index:15;
  color:#cbd5e1;
}
#hud.depth { color:var(--accent); }
#hud.plane { color:#fbbf24; }

/* zoom loupe */
#loupe-wrap {
  position:fixed;
  top:92px; right:14px;
  width:108px; height:108px;
  border-radius:50%;
  overflow:hidden;
  border:2.5px solid rgba(255,255,255,0.92);
  box-shadow:0 6px 22px rgba(0,0,0,0.55);
  z-index:14;
  display:none;
  transition:border-color 0.15s, box-shadow 0.15s;
}
#loupe { width:108px; height:108px; display:block; }
#loupe-cross { position:absolute; top:50%; left:50%; width:14px; height:14px; transform:translate(-50%,-50%); pointer-events:none; }
#loupe-cross::before, #loupe-cross::after { content:''; position:absolute; background:var(--accent); box-shadow:0 0 3px rgba(0,0,0,0.85); }
#loupe-cross::before { left:50%; top:0; width:2px; height:100%; transform:translateX(-50%); }
#loupe-cross::after  { top:50%; left:0; height:2px; width:100%; transform:translateY(-50%); }
#loupe-label {
  position:absolute; bottom:5px; left:50%; transform:translateX(-50%);
  font-size:0.58rem; font-weight:800; letter-spacing:0.06em;
  color:#fff; text-shadow:0 1px 3px #000; pointer-events:none;
}
#loupe-wrap.edge { border-color:var(--danger); box-shadow:0 0 16px rgba(239,68,68,0.7); }

/* center crosshair */
#crosshair {
  position:fixed; top:50%; left:50%;
  width:36px; height:36px;
  transform:translate(-50%, -50%);
  border:2px solid rgba(255,255,255,0.92);
  border-radius:50%;
  pointer-events:none;
  z-index:14;
  box-shadow:0 0 10px rgba(0,0,0,0.5);
  transition:border-color 0.15s, box-shadow 0.15s;
}
#crosshair::after {
  content:''; position:absolute; top:50%; left:50%;
  width:6px; height:6px; background:var(--accent); border-radius:50%;
  transform:translate(-50%, -50%); box-shadow:0 0 8px rgba(123,140,255,0.95);
}
#crosshair.edge { border-color:var(--danger); box-shadow:0 0 12px rgba(239,68,68,0.85); }
#crosshair.edge::after { background:var(--danger); box-shadow:0 0 6px rgba(239,68,68,0.95); }

/* top instruction */
#instruction {
  position:fixed; top:22px; left:50%;
  transform:translateX(-50%);
  background:rgba(13,19,32,0.7);
  backdrop-filter:blur(10px);
  border:1px solid rgba(255,255,255,0.08);
  padding:10px 18px;
  border-radius:999px;
  font-size:0.9rem;
  font-weight:600;
  z-index:13;
  max-width:84vw;
  text-align:center;
}

/* toast */
#toast {
  position:fixed; bottom:120px; left:50%;
  transform:translateX(-50%);
  background:rgba(185,28,28,0.95);
  backdrop-filter:blur(8px);
  padding:10px 18px;
  border-radius:999px;
  font-size:0.85rem; font-weight:600;
  display:none; align-items:center;
  max-width:80vw; text-align:center;
  z-index:17;
}

/* live "moving too fast" warning */
#speed-warn {
  position:fixed; bottom:178px; left:50%;
  transform:translateX(-50%);
  background:rgba(220,38,38,0.96);
  backdrop-filter:blur(8px);
  padding:11px 22px;
  border-radius:999px;
  font-size:0.92rem; font-weight:800; letter-spacing:0.01em;
  display:none;
  z-index:19;
  box-shadow:0 6px 24px rgba(239,68,68,0.5);
  animation:speed-pulse 0.9s ease-in-out infinite;
}
@keyframes speed-pulse { 0%,100% { transform:translateX(-50%) scale(1); } 50% { transform:translateX(-50%) scale(1.04); } }

/* finalizing pill — shown while the measurement settles after point 2 */
#finalizing {
  position:fixed; bottom:120px; left:50%;
  transform:translateX(-50%);
  display:none; align-items:center; gap:10px;
  background:rgba(13,19,32,0.92);
  backdrop-filter:blur(10px);
  border:1px solid rgba(123,140,255,0.35);
  padding:11px 20px;
  border-radius:999px;
  font-size:0.9rem; font-weight:600;
  z-index:19;
  box-shadow:0 6px 24px rgba(0,0,0,0.4);
}
#finalizing .spin {
  width:16px; height:16px; flex-shrink:0;
  border:2.5px solid rgba(123,140,255,0.3);
  border-top-color:var(--accent);
  border-radius:50%;
  animation:fin-spin 0.7s linear infinite;
}
@keyframes fin-spin { to { transform:rotate(360deg); } }

/* bottom bar */
#bottom-bar {
  position:fixed; bottom:30px; left:0; right:0;
  display:flex; justify-content:center; gap:14px;
  z-index:16;
}
.bar-btn {
  background:rgba(255,255,255,0.12);
  backdrop-filter:blur(12px);
  border:1px solid rgba(255,255,255,0.12);
  color:#fff;
  border-radius:999px;
  padding:14px 30px;
  font-size:1rem; font-weight:700;
  transition:transform 0.12s;
}
.bar-btn.primary {
  background:linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 100%);
  color:var(--accent-ink);
  border:none;
  box-shadow:0 8px 24px rgba(123,140,255,0.4);
}
.bar-btn:active { transform:scale(0.94); }

/* result sheet */
#result-sheet {
  position:fixed; bottom:0; left:0; right:0;
  background:linear-gradient(180deg, rgba(19,28,46,0.96) 0%, rgba(7,11,18,0.98) 100%);
  backdrop-filter:blur(16px);
  border-top:1px solid rgba(255,255,255,0.08);
  border-radius:26px 26px 0 0;
  padding:26px 24px 36px;
  display:none; flex-direction:column; align-items:center; gap:6px;
  z-index:18;
  box-shadow:0 -10px 40px rgba(0,0,0,0.5);
}
#res-label { font-size:0.82rem; color:var(--muted); letter-spacing:0.12em; text-transform:uppercase; }
#res-value {
  font-size:2.9rem; font-weight:800; letter-spacing:-0.01em;
  background:linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 100%);
  -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color:transparent;
}
.res-actions { display:flex; gap:14px; margin-top:16px; }
.res-actions button { border:none; border-radius:999px; padding:14px 26px; font-size:0.95rem; font-weight:700; transition:transform 0.12s; }
#again-btn { background:rgba(255,255,255,0.12); border:1px solid rgba(255,255,255,0.12); color:#fff; }
#save2-btn { background:linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 100%); color:var(--accent-ink); box-shadow:0 8px 24px rgba(123,140,255,0.4); }
.res-actions button:active { transform:scale(0.94); }

/* ── Onboarding carousel (Good Lighting / Move Slowly) ──────────────────── */
#calib-overlay {
  position:fixed; inset:0;
  display:none;
  flex-direction:column; align-items:center; justify-content:space-between;
  padding:70px 24px 40px;
  z-index:60;
  background:linear-gradient(180deg, rgba(7,11,18,0.72) 0%, rgba(7,11,18,0.42) 45%, rgba(7,11,18,0.78) 100%);
  opacity:0; transition:opacity 0.35s;
}
#calib-overlay.show { display:flex; opacity:1; }
.calib-center { flex:1; display:flex; flex-direction:column; align-items:center; justify-content:center; gap:20px; }
.calib-icon { animation:calib-bob 2.4s ease-in-out infinite; }
@keyframes calib-bob { 0%,100% { transform:translateY(0); } 50% { transform:translateY(-10px); } }
.calib-title { font-size:1.05rem; color:rgba(255,255,255,0.92); letter-spacing:0.02em; }
.calib-card {
  background:rgba(19,28,46,0.9);
  backdrop-filter:blur(16px);
  border-radius:22px;
  padding:24px 22px 18px;
  text-align:center;
  max-width:340px; width:100%;
  position:relative;
  border:1px solid rgba(123,140,255,0.18);
  box-shadow:0 10px 36px rgba(0,0,0,0.55);
}
.calib-badge {
  display:inline-block;
  background:linear-gradient(100deg, var(--accent) 0%, var(--accent-2) 100%);
  color:var(--accent-ink);
  border-radius:999px; padding:5px 13px;
  font-size:0.72rem; font-weight:800; letter-spacing:0.02em;
  position:absolute; top:-12px; left:50%; transform:translateX(-50%);
  white-space:nowrap;
}
.calib-tip-title { font-size:1.18rem; font-weight:800; color:#fff; margin:8px 0 6px; }
.calib-tip-body  { font-size:0.9rem; color:rgba(255,255,255,0.72); line-height:1.5; margin-bottom:16px; }
.calib-dots { display:flex; gap:6px; justify-content:center; align-items:center; }
.calib-dots .dot { width:6px; height:6px; border-radius:50%; background:rgba(255,255,255,0.25); transition:background 0.25s, width 0.25s; }
.calib-dots .dot.active { background:var(--accent); width:18px; border-radius:3px; }
.calib-hint { font-size:0.78rem; color:rgba(255,255,255,0.55); margin-top:14px; }