const hour = document.getElementById("hour"); const min = document.getElementById("min"); const sec = document.getElementById("sec"); function countdown() { const now = new Date(); // 現在時刻を取得 const tomorrow = new Date(now.getFullYear(),now.getMonth(),now.getDate()+1); // 明日の0:00を取得 const diff = tomorrow.getTime() - now.getTime(); // 時間の差を取得(ミリ秒) // ミリ秒から単位を修正 const calcHour = Math.floor(diff / 1000 / 60 / 60); const calcMin = Math.floor(diff / 1000 / 60) % 60; const calcSec = Math.floor(diff / 1000) % 60; // 取得した時間を表示(2桁表示) hour.innerHTML = calcHour < 10 ? '0' + calcHour : calcHour; min.innerHTML = calcMin < 10 ? '0' + calcMin : calcMin; sec.innerHTML = calcSec < 10 ? '0' + calcSec : calcSec; } countdown(); setInterval(countdown,1000);