<title>mY fIRST cALCULATOR</title> <style> #calc-contain { position: relative; width: 300px; border: 2px solid black; border-radius: 4px; } input type="button" { background: black; width: 20%; border-radius: 4px; margin: 2%; font-weight: 900; font-size: 20px; } input [type=text] { position: relative; display: black; width: 90px; margin: 5px auto; font-size: 20px; } </style>