assets/js/admin/customizer-layout.js
/**
* Theme Customizer layout control JS.
*/
jQuery( function( $ ) {
// custom controls
$( document ).on( 'click', '.layout-button', function() {
var clicked = $( this ),
parent = clicked.closest( '.layouts-selector' ),
input = parent.find( '.selected-layout' );
parent.find( '.layout-button' ).css( 'border', '1px solid transparent' );
clicked.css( 'border', '1px solid rgb(43, 166, 203)' );
$( input ).val( clicked.data('option') ).trigger( 'change' );
});
} );