I added this script.
<script type="text/javascript">
wp.customize(
'theme_layout_control',
function( value ) {
value.bind(
function( to ) {
var classes = jQuery( 'body' ).attr( 'class' ).replace( /layout-[a-zA-Z0-9_-]*/g, '' );
jQuery( 'body' ).attr( 'class', classes ).addClass( 'layout-' + to );
}
);
}
);
</script>