:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #14141f;
  --bg-tertiary: #1e1e2e;
  --text-primary: #ffffff;
  --text-secondary: #a0a0b0;
  --text-muted: #606070;
  --accent: #00d4ff;
  --accent-secondary: #00ff88;
  --danger: #ff4466;
  --focus-ring: #00d4ff;
  --focus-glow: rgba(0, 212, 255, 0.4);
  --radius-md: 12px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html, body {
  width: 600px; height: 600px; overflow: hidden;
  background: #000;
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}
#app { width: 100%; height: 100%; position: relative; }
.screen { width: 100%; height: 100%; position: absolute; top: 0; left: 0; display: flex; flex-direction: column; }
.screen.hidden { display: none; }
.focusable { transition: all 0.15s ease; border: 2px solid transparent; cursor: pointer; outline: none; }
.focusable:focus { border-color: var(--focus-ring); box-shadow: 0 0 20px var(--focus-glow); }
.hidden { display: none !important; }

/* ---------- Header ---------- */
.app-header {
  display: flex; align-items: center; justify-content: space-between;
  height: 60px; padding: 0 22px; flex-shrink: 0;
  background: var(--bg-secondary);
  border-bottom: 1px solid rgba(255,255,255,0.06);
}
.logo { font-size: 22px; font-weight: 700; letter-spacing: 0.3px; display: flex; align-items: center; gap: 8px; }
.logo-mark { color: var(--accent); }

/* ---------- Buttons ---------- */
.btn {
  display: flex; align-items: center; justify-content: center; gap: 10px;
  width: 100%; min-height: 64px; padding: 0 20px;
  background: var(--bg-tertiary);
  color: var(--text-primary);
  font-size: 20px; font-weight: 600;
  border-radius: var(--radius-md);
  font-family: inherit;
}
.btn-primary {
  min-height: 92px;
  font-size: 24px; font-weight: 800;
  color: #001014;
  background: linear-gradient(135deg, var(--accent), var(--accent-secondary));
}
.btn-primary .btn-mark { font-size: 26px; }
.btn-ghost { background: transparent; color: var(--text-secondary); font-size: 17px; min-height: 52px; }

/* ---------- Home ---------- */
.home-body {
  flex: 1; display: flex; flex-direction: column; gap: 14px;
  padding: 24px 26px;
}
.stat-row { display: flex; gap: 14px; margin-bottom: 4px; }
.stat-chip {
  flex: 1; display: flex; flex-direction: column; gap: 4px;
  padding: 14px 18px;
  background: var(--bg-primary);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: var(--radius-md);
}
.stat-label { font-size: 13px; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1px; }
.stat-value { font-size: 34px; font-weight: 800; color: var(--accent); font-variant-numeric: tabular-nums; }

/* ---------- Counter ---------- */
.counter-header { background: var(--bg-secondary); }
.sensor-status { display: flex; align-items: center; gap: 8px; font-size: 15px; color: var(--text-secondary); }
.sensor-status .dot { width: 10px; height: 10px; border-radius: 50%; background: var(--text-muted); }
.sensor-status[data-on="1"] .dot { background: var(--accent-secondary); box-shadow: 0 0 8px var(--accent-secondary); }
.sensor-status[data-on="0"] .dot { background: #ffaa33; box-shadow: 0 0 8px #ffaa33; }
.rate { font-size: 15px; color: var(--text-secondary); font-variant-numeric: tabular-nums; }

.counter-body {
  flex: 1; display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 18px; padding: 12px;
}
.count-wrap { display: flex; flex-direction: column; align-items: center; }
.count-number {
  font-size: 120px; line-height: 1; font-weight: 800;
  font-variant-numeric: tabular-nums;
  color: #fff;
  background: linear-gradient(180deg, #ffffff, var(--accent) 65%, var(--accent-secondary));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.count-label { font-size: 18px; color: var(--text-secondary); letter-spacing: 2px; text-transform: uppercase; margin-top: 2px; }
@keyframes pop { 0% { transform: scale(1); } 30% { transform: scale(1.18); } 100% { transform: scale(1); } }
.count-number.pulse { animation: pop 0.35s ease; }

.meter { display: flex; justify-content: center; }
.meter-track {
  position: relative; width: 56px; height: 196px;
  background: var(--bg-tertiary);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 28px; overflow: hidden;
}
.meter-fill-pos {
  position: absolute; left: 0; right: 0; bottom: 50%; height: 0;
  background: linear-gradient(0deg, var(--accent), var(--accent-secondary));
}
.meter-fill-neg {
  position: absolute; left: 0; right: 0; top: 50%; height: 0;
  background: linear-gradient(180deg, var(--accent), #0088bb);
}
.meter-mid { position: absolute; left: 0; right: 0; top: 50%; height: 2px; background: var(--text-muted); transform: translateY(-1px); }
.meter-thresh { position: absolute; left: 0; right: 0; height: 2px; background: var(--danger); opacity: 0.75; }
#counter[data-mode="manual"] .meter { opacity: 0.2; }

.phase-text { font-size: 19px; font-weight: 600; color: var(--text-secondary); min-height: 24px; letter-spacing: 0.5px; }
.phase-text.air { color: var(--accent); }
.phase-text.land { color: var(--accent-secondary); }

.counter-nav {
  display: flex; gap: 10px; padding: 14px 16px; flex-shrink: 0;
  background: var(--bg-secondary);
  border-top: 1px solid rgba(255,255,255,0.06);
}
.nav-btn { min-height: 72px; font-size: 18px; padding: 0 8px; }

/* ---------- Settings ---------- */
.settings-body { flex: 1; display: flex; flex-direction: column; gap: 22px; padding: 26px; }
.setting-group { display: flex; flex-direction: column; gap: 12px; }
.setting-row { flex-direction: row; align-items: center; justify-content: space-between; }
.setting-title { font-size: 19px; font-weight: 600; }
.setting-hint { font-size: 14px; color: var(--text-secondary); }
.seg { display: flex; gap: 10px; }
.seg-btn {
  flex: 1; min-height: 64px;
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  font-size: 18px; font-weight: 600;
  border-radius: var(--radius-md);
  font-family: inherit;
}
.seg-btn.active { background: linear-gradient(135deg, var(--accent), var(--accent-secondary)); color: #001014; }
.toggle { width: auto; min-width: 96px; min-height: 56px; font-size: 18px; }
.toggle.on { background: linear-gradient(135deg, var(--accent), var(--accent-secondary)); color: #001014; }

/* ---------- Help ---------- */
.help-body { flex: 1; display: flex; flex-direction: column; gap: 14px; padding: 24px 26px; }
.help-body p { font-size: 17px; line-height: 1.5; color: var(--text-primary); }
.help-body ul { display: flex; flex-direction: column; gap: 10px; padding-left: 22px; }
.help-body li { font-size: 16px; line-height: 1.45; color: var(--text-secondary); }
.help-body strong { color: var(--text-primary); }
.help-keys { font-size: 14px; color: var(--text-muted); }
.help-body .btn { margin-top: auto; }

/* ---------- Toast ---------- */
.toast {
  position: absolute; left: 50%; bottom: 26px;
  transform: translateX(-50%) translateY(10px);
  background: var(--bg-tertiary); color: #fff;
  padding: 12px 22px; border-radius: 24px;
  font-size: 16px; font-weight: 600;
  border: 1px solid rgba(255,255,255,0.12);
  opacity: 0; transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 50; pointer-events: none;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }