body,html,#root{height:100%;margin:0;display:flex;justify-content:center;align-items:center;background-color:#f0f0f0;font-family:Arial,sans-serif}.calculadora{background:#fff;border-radius:12px;padding:20px;box-shadow:0 8px 20px #0000001a;width:320px}.display{background:#222;color:#fff;font-size:2rem;padding:15px 20px;border-radius:8px;margin-bottom:15px;text-align:right;-webkit-user-select:none;user-select:none}.teclado{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}button{padding:18px;font-size:1.2rem;border:none;border-radius:8px;background-color:#e0e0e0;cursor:pointer;transition:background-color .2s ease}button:hover{background-color:#d0d0d0}body,html,#root{height:100%;margin:0;display:flex;justify-content:center;align-items:center;background-color:#161718;font-family:Arial,sans-serif}.calculadora{max-width:320px;padding:1rem;border:1px solid #ccc;border-radius:10px;background:#fff;box-shadow:0 4px 12px #0000001a}