*{box-sizing:border-box}body{font-family:monospace;background:#fff;color:#000;margin:0;padding:20px;font-size:14px}button{font-family:monospace;font-size:14px;border:1px solid black;background:#fff;cursor:pointer;padding:5px 10px;margin:2px}button:hover{background:#eee}input,textarea{font-family:monospace;font-size:14px;border:1px solid black;padding:5px;margin:2px}table{border-collapse:collapse;width:100%}th,td{border:1px solid black;padding:5px;text-align:left}th{background:#eee}pre{background:#f5f5f5;border:1px solid #ccc;padding:10px;overflow-x:auto;font-size:12px}.error{color:red;border:1px solid red;padding:10px;margin:10px 0}.tabs{margin-bottom:20px;border-bottom:1px solid black;padding-bottom:10px}.tabs button.active{background:#000;color:#fff}.section{margin:20px 0}h1,h2,h3{margin:10px 0}