.wpd-calculator{background-color:#333;border-radius:10px;padding:20px;box-shadow:0 4px 8px rgb(0 0 0 / .2);width:400px;margin:0 auto}.wpd-display-container{background-color:#fff;padding:10px;margin-bottom:10px;border-radius:5px}.wpd-expression{min-height:20px;font-size:16px;color:#666;text-align:right;margin-bottom:5px;word-wrap:break-word}.wpd-display{text-align:right;font-size:24px;min-height:40px;word-wrap:break-word}.wpd-error-message{color:#e74c3c;font-size:12px;text-align:right;min-height:16px;margin-top:4px}.wpd-buttons{display:grid;grid-template-columns:repeat(5,1fr);gap:5px}.wpd-calculator button{padding:15px 5px;font-size:16px;border:none;border-radius:5px;cursor:pointer;background-color:#666;color:#fff;transition:background-color 0.2s}.wpd-calculator button:hover{background-color:#888}.wpd-calculator button.wpd-operator{background-color:#ff9500}.wpd-calculator button.wpd-operator:hover{background-color:#fa3}.wpd-calculator button.wpd-equals{background-color:#2ecc71}.wpd-calculator button.wpd-equals:hover{background-color:#27ae60}.wpd-calculator button.wpd-clear,.wpd-calculator button.wpd-backspace{background-color:#e74c3c}.wpd-calculator button.wpd-clear:hover,.wpd-calculator button.wpd-backspace:hover{background-color:#c0392b}.wpd-calculator button.wpd-function{background-color:#3498db}.wpd-calculator button.wpd-function:hover{background-color:#2980b9}.wpd-keyboard-shortcuts{color:#fff;font-size:12px;text-align:center;margin-top:10px}@media (max-width:480px){.wpd-calculator{width:100%;padding:10px}.wpd-calculator button{padding:10px 5px;font-size:14px}}