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'use strict';

( function() {
	var hasAdminBar = document.body.classList.contains( 'admin-bar' ),
		siteHeader = document.querySelector( '.site-header' );

	if ( !hasAdminBar ) {
		return;
	}

	var trackHeader = function() {
		// 600 is the breakpoint for the WP admin bar
		if ( window.innerWidth < 600 ) {
			if ( window.scrollY < 46 ) {
				siteHeader.style.top = 46 - window.scrollY + 'px';
			} else {
				siteHeader.style.top = 0;
			}
		} else {
			siteHeader.style.top = '';
		}
	};

	window.addEventListener( 'scroll', trackHeader );
} )();