Hello,

Please add this code to the Theme Settings > Custom CSS > Global:

body .login-form-side .register-question:before {
display:none;
}
body .basel-registration-page .form-row .woocommerce-Button, body .basel-registration-page .btn.btn-color-black.basel-switch-to-register {
    background-color: red!important;
    border-color: red!important;
    color: #ffffff!important;
}
body .basel-registration-page .form-row .woocommerce-Button:hover, body .basel-registration-page .btn.btn-color-black.basel-switch-to-register:hover {
    background-color: green!important;
    border-color: green!important;
    color: #ffffff!important;
}

Replace the color as per your needs

Best Regards