body{font-family:Arial,sans-serif;line-height:1.6;margin:0;padding:20px;color:#333}.app{max-width:1000px;margin:0 auto}h1,h2,h3{color:#2c3e50}.section{background:#f9f9f9;padding:20px;margin-bottom:20px;border-radius:5px;box-shadow:0 2px 5px #0000001a}.form-group{margin-bottom:15px}label{display:block;margin-bottom:5px;font-weight:700}input[type=text],input[type=number],select{width:100%;padding:8px;border:1px solid #ddd;border-radius:4px;box-sizing:border-box}input[type=checkbox]{margin-right:10px}button{background:#3498db;color:#fff;border:none;padding:10px 15px;border-radius:4px;cursor:pointer;margin-right:10px}button:hover{background:#2980b9}.navigation{display:flex;margin-bottom:20px;overflow-x:auto}.navigation button{white-space:nowrap;margin-right:5px}.xml-preview{background:#333;color:#f8f8f8;padding:15px;border-radius:4px;overflow-x:auto;max-height:500px}@media (max-width: 768px){.navigation{flex-direction:column}.navigation button{margin-bottom:5px;width:100%}}