.pipe-sizing-calculator{max-width:600px;margin:20px auto;padding:20px;background:#f9f9f9;border-radius:8px}.form-group{margin-bottom:15px}.form-group label{display:block;margin-bottom:5px}.form-group select,.form-group input{width:100%;padding:8px;margin-bottom:10px;border:1px solid #ddd;border-radius:4px}button[type="submit"],#reset-button{background:#0073aa;color:#fff;padding:10px 20px;border:none;border-radius:4px;cursor:pointer;margin-right:10px}#pipesize-results{margin-top:20px;padding:15px;background:#fff;border-radius:4px}.result-item{margin:10px 0}.error{color:#dc3232}.loading{color:#0073aa}