.calc-toggle { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; }
.calc-toggle button[aria-pressed="true"] { background: var(--accent); color: var(--on-accent); }
.calc-display { padding: 12px; border: 1px solid var(--line); border-radius: 12px; background: var(--bg); text-align: right; font-variant-numeric: tabular-nums; }
#expr { margin: 0; min-height: 1.6em; color: var(--muted); overflow-wrap: anywhere; }
#out { display: block; min-height: 1.25em; font-size: clamp(1.8rem, 9vw, 2.6rem); font-weight: 600; line-height: 1.25; overflow-wrap: anywhere; }
#sci { display: grid; gap: 8px; }
.keys { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px; }
.keys button { min-height: 56px; padding: 0; font-size: 1.35rem; touch-action: manipulation; user-select: none; }
.keys.sci button { min-height: 48px; font-size: 1.05rem; }
.keys .num { background: var(--bg); color: var(--fg); border: 1px solid var(--line); }
.keys .wide { grid-column: span 2; }
#history-box h2 { margin: 0; }
#history { display: grid; gap: 6px; }
#history button { text-align: right; overflow-wrap: anywhere; font-weight: 600; font-variant-numeric: tabular-nums; }