body {
                font-family: sans-serif;
                max-width: 420px;
                margin: 80px auto;
                padding: 20px;
            }

            label {
                display: block;
                margin-bottom: 6px;
            }

            input {
                width: 100%;
                box-sizing: border-box;
                padding: 10px;
                margin-bottom: 15px;
            }

            button {
                padding: 10px 20px;
            }

            .error {
                margin-bottom: 15px;
                padding: 10px;
                border: 1px solid #c00;
            }