: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; }

/* ---- shared chrome ---- */
.topbar {
  padding: 28px 28px 18px;
  border-bottom: 1px solid var(--bg-tertiary);
}
.title { font-size: 38px; font-weight: 700; letter-spacing: -0.5px; }
.subtitle { font-size: 20px; color: var(--text-secondary); margin-top: 6px; }
.hint {
  margin-top: auto;
  padding: 16px 28px;
  font-size: 18px;
  color: var(--text-muted);
  border-top: 1px solid var(--bg-tertiary);
  text-align: center;
}

/* ---- home menu ---- */
.menu { display: flex; flex-direction: column; gap: 16px; padding: 24px; }
.menu-item {
  display: flex; align-items: center; gap: 20px;
  min-height: 96px; padding: 0 24px;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  text-align: left;
}
.menu-icon {
  width: 60px; height: 60px; flex: 0 0 60px;
  display: flex; align-items: center; justify-content: center;
  font-size: 34px; font-weight: 700;
  background: var(--bg-tertiary);
  border-radius: 14px;
  color: var(--accent);
}
.menu-text { display: flex; flex-direction: column; }
.menu-label { font-size: 26px; font-weight: 600; }
.menu-sub { font-size: 18px; color: var(--text-secondary); margin-top: 2px; }

/* ---- grid of number tiles ---- */
.grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  padding: 22px;
  align-content: start;
}
.tile {
  min-height: 84px;
  display: flex; align-items: center; justify-content: center;
  font-size: 34px; font-weight: 700;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  color: var(--text-primary);
}
.tile.wide { grid-column: span 4; font-size: 28px; min-height: 64px; color: var(--accent); }

/* ---- drill ---- */
.drillbar {
  display: flex; justify-content: space-between; align-items: center;
  padding: 20px 24px;
  border-bottom: 1px solid var(--bg-tertiary);
}
.pill {
  font-size: 20px; font-weight: 600;
  padding: 8px 16px;
  background: var(--bg-tertiary);
  border-radius: 999px;
  color: var(--text-secondary);
}
.pill.streak { color: var(--accent-secondary); }
.qwrap {
  flex: 0 0 auto;
  padding: 26px 24px 10px;
  text-align: center;
}
.question { font-size: 80px; font-weight: 800; letter-spacing: -1px; line-height: 1; }
.qmark { font-size: 30px; color: var(--text-secondary); margin-top: 10px; }
.choices {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  padding: 18px 24px;
}
.choice {
  min-height: 110px;
  display: flex; align-items: center; justify-content: center;
  font-size: 46px; font-weight: 700;
  background: var(--bg-tertiary);
  border-radius: var(--radius-md);
  color: var(--text-primary);
}
.choice.correct {
  background: rgba(0, 255, 136, 0.18);
  border-color: var(--accent-secondary);
  color: var(--accent-secondary);
}
.choice.wrong {
  background: rgba(255, 68, 102, 0.18);
  border-color: var(--danger);
  color: var(--danger);
}
.drillbar .pill, .choice { transition: all 0.15s ease; }

/* ---- result ---- */
.result-body { flex: 1; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 14px; }
.score { font-size: 96px; font-weight: 800; color: var(--accent); line-height: 1; }
.score-acc { font-size: 30px; color: var(--text-primary); }
.score-streak { font-size: 20px; color: var(--text-secondary); }

/* ---- table view ---- */
.tv-list {
  flex: 1; overflow: hidden;
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-auto-rows: min-content;
  gap: 10px 18px;
  padding: 22px 28px;
  align-content: start;
}
.tv-row {
  display: flex; justify-content: space-between; align-items: center;
  font-size: 26px; font-weight: 600;
  padding: 8px 16px;
  background: var(--bg-secondary);
  border-radius: 10px;
}
.tv-row .eq { color: var(--accent); }

/* ---- stats ---- */
.stats-body { padding: 24px; display: flex; flex-direction: column; gap: 12px; }
.stat-row {
  display: flex; justify-content: space-between; align-items: center;
  padding: 18px 22px;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
}
.stat-label { font-size: 22px; color: var(--text-secondary); }
.stat-val { font-size: 28px; font-weight: 700; color: var(--text-primary); }

/* ---- buttons ---- */
.actions { padding: 18px 24px; display: flex; flex-direction: column; gap: 14px; }
.bigbtn {
  min-height: 88px;
  font-size: 26px; font-weight: 600;
  background: var(--accent);
  color: #001018;
  border-radius: var(--radius-md);
}
.bigbtn.ghost { background: var(--bg-secondary); color: var(--text-primary); }
.bigbtn.danger { color: var(--danger); }