body{font-family:'Arial',sans-serif;background-color:#f4f4f9;color:#333;margin:0;padding:0;display:flex;justify-content:center;align-items:center;min-height:100vh}.calculator-container{background:#fff;padding:2rem;border-radius:10px;box-shadow:0 4px 10px rgba(0,0,0,.1);max-width:400px;width:100%}h1{font-size:1.8rem;margin-bottom:1.5rem;color:#2c3e50;text-align:center}.input-group{margin-bottom:1rem}label{display:block;font-weight:700;margin-bottom:.5rem;color:#555}input,select{width:100%;padding:.75rem;border:1px solid #ddd;border-radius:5px;font-size:1rem;margin-bottom:.5rem}button{width:100%;padding:.75rem;background-color:#3498db;color:#fff;border:none;border-radius:5px;font-size:1rem;cursor:pointer;transition:background-color .3s ease}button:hover{background-color:#2980b9}.results{margin-top:1.5rem;padding:1rem;background-color:#ecf0f1;border-radius:5px}.results h2{font-size:1.5rem;margin-bottom:1rem;color:#2c3e50}.results p{margin:.5rem 0;font-size:1rem;color:#333}.instructions{margin-top:1.5rem;padding:1rem;background-color:#f9f9f9;border-radius:5px}.instructions h2{font-size:1.5rem;margin-bottom:1rem;color:#2c3e50}.instructions ol{padding-left:1.5rem}.instructions li{margin-bottom:.5rem;font-size:1rem;color:#555}