This is test product 1. // Date variables for easy modification var startDate = new Date("January 21, 2024"); // Start date for the warning to show var endDate = new Date("January 31, 2024"); // End date for the warning to stop showing var ReferenceDateA = new Date("January 23, 2024"); // Reference Date A var ReferenceDateB = new Date("January 30, 2024"); // Reference Date B var today = new Date(); today.setTime(today.getTime() + (9 * 60 * 60 * 1000)); var oneWeek = 7 * 24 * 60 * 60 * 1000; // days*hours*minutes*seconds*milliseconds // Check if today is between the start and end dates if (today >= startDate && today < endDate) { var diffWeeksA = Math.round(Math.abs((ReferenceDateA.getTime() - today.getTime()) / oneWeek)); var diffWeeksB = Math.round(Math.abs((ReferenceDateB.getTime() - today.getTime()) / oneWeek)); document.write('' + '' + '' + '' + '---- 更新 (1月23日) ---- 大人気商品により、発送完了まで更に' + '' + diffWeeksA + '〜' + diffWeeksB + '週間' + 'いただいております。' + '' + '' + '' + '' + ''); }