:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #14141f;
  --bg-tertiary: #1e1e2e;
  --text-primary: #ffffff;
  --text-secondary: #a0a0b0;
  --text-muted: #606070;
  --accent: #00d4ff;
  --accent-secondary: #00ff88;
  --exhale: #8a7cff;
  --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;
  -webkit-font-smoothing: antialiased;
}

#app { width: 100%; height: 100%; position: relative; }

.screen {
  width: 100%; height: 100%;
  position: absolute; top: 0; left: 0;
  display: flex; flex-direction: column;
  padding: 32px;
}
.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 { text-align: center; padding-top: 8px; }
.app-title {
  font-size: 38px; font-weight: 700; letter-spacing: 0.5px;
  background: linear-gradient(90deg, var(--accent), var(--accent-secondary));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.app-sub {
  margin-top: 6px; font-size: 18px;
  color: var(--text-secondary); letter-spacing: 2px;
}

/* ---------- Buttons ---------- */
.actions {
  display: flex; flex-direction: column; gap: 16px;
  width: 100%; margin-top: auto;
}
.btn {
  width: 100%; min-height: 80px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px; font-weight: 600;
  color: var(--text-primary);
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
}
.btn-primary {
  background: linear-gradient(135deg, #103a44, #0c2e3a);
  color: var(--accent);
}
.btn-danger { color: var(--danger); }

/* ---------- Home ---------- */
.home-body { flex: 1; display: flex; flex-direction: column; }
.stat-row {
  display: flex; justify-content: space-around;
  margin: 28px 0;
}
.stat {
  display: flex; flex-direction: column; align-items: center;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: 16px 18px; min-width: 150px;
}
.stat-num { font-size: 40px; font-weight: 700; color: var(--accent); }
.stat-label {
  margin-top: 4px; font-size: 15px;
  color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1px;
}

/* ---------- Session ---------- */
#session { padding: 24px 32px; align-items: center; }
.session-top {
  font-size: 20px; font-weight: 600;
  color: var(--text-secondary); letter-spacing: 1px;
  padding: 6px 0;
}
.breath-stage {
  --phase-color: var(--text-secondary);
  flex: 1;
  position: relative;
  width: 340px; height: 340px;
  display: flex; align-items: center; justify-content: center;
  margin: 4px auto;
}
.ring {
  position: absolute; inset: 50% auto auto 50%;
  width: 340px; height: 340px;
  transform: translate(-50%, -50%) rotate(-90deg);
}
.ring-track {
  fill: none; stroke: var(--bg-tertiary); stroke-width: 8;
}
.ring-progress {
  fill: none; stroke: var(--phase-color); stroke-width: 8;
  stroke-linecap: round;
  filter: drop-shadow(0 0 6px var(--phase-color));
  transition: stroke 0.5s ease;
}
.orb {
  position: absolute;
  top: 50%; left: 50%;
  width: 170px; height: 170px; margin: -85px 0 0 -85px;
  border-radius: 50%;
  background: radial-gradient(circle at 50% 38%, var(--phase-color), rgba(10,10,15,0.1) 72%);
  box-shadow: 0 0 70px -8px var(--phase-color), inset 0 0 30px -10px var(--phase-color);
  transform: scale(0.55);
  transform-origin: center;
  transition: background 0.6s ease, box-shadow 0.6s ease;
  will-change: transform;
}
.breath-center {
  position: relative; z-index: 2;
  text-align: center; pointer-events: none;
}
.phase-label {
  font-size: 26px; font-weight: 600;
  color: var(--text-primary);
  text-shadow: 0 1px 8px rgba(0,0,0,0.8);
}
.phase-count {
  font-size: 84px; font-weight: 700; line-height: 1;
  color: var(--phase-color);
  text-shadow: 0 2px 14px rgba(0,0,0,0.7);
}
.phase-hint {
  font-size: 16px; color: var(--text-secondary);
  max-width: 200px; margin: 0 auto;
  text-shadow: 0 1px 6px rgba(0,0,0,0.9);
}
.session-controls {
  display: flex; gap: 16px; width: 100%; margin-top: 4px;
}
.session-controls .btn { min-height: 72px; font-size: 20px; }

/* ---------- Complete ---------- */
.complete-body { flex: 1; display: flex; flex-direction: column; }
.complete-stats {
  display: flex; justify-content: space-around;
  margin: 36px 0;
}
.cstat {
  display: flex; flex-direction: column; align-items: center;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: 20px 16px; min-width: 150px;
}
.cstat-num { font-size: 38px; font-weight: 700; color: var(--accent-secondary); }
.cstat-label {
  margin-top: 6px; font-size: 15px;
  color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1px;
}

/* ---------- Learn ---------- */
.learn-body { flex: 1; display: flex; flex-direction: column; }
.steps {
  list-style: none; margin: 20px 0 16px;
  display: flex; flex-direction: column; gap: 14px;
}
.steps li {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: 16px 18px; font-size: 19px;
  color: var(--text-secondary); line-height: 1.4;
}
.steps b { color: var(--text-primary); }
.s-in { color: var(--accent) !important; }
.s-hold { color: var(--accent-secondary) !important; }
.s-out { color: var(--exhale) !important; }
.learn-note {
  font-size: 17px; color: var(--text-secondary);
  line-height: 1.5; padding: 0 4px;
}