:root{font-size:16px;font-family:Arial,Helvetica,sans-serif;--primary: #3498db;--white: #ecf0f1;--white-transparent: rgba(237, 241, 242, .8);--midnight: #2c3e50;--lighter-midnight: #34495e;--yellow: #f1c40f;--red: #e74c3c}*{padding:0;margin:0;box-sizing:border-box;-webkit-user-select:none;user-select:none}body{position:relative;height:100vh;background:var(--midnight)}input{border:none;outline:none;font-size:1.5rem}a{color:var(--yellow);text-decoration:underline;cursor:pointer}.red,.error{color:var(--red)}.disabled{opacity:.6}.not-allowed{cursor:not-allowed}.hidden{display:none}