JavaScript Exercise Countdown Timer

Build a JavaScript countdown timer from scratch, using local storage to persist the selected date across refreshes. Learn to manipulate the DOM and perform date calculations to display remaining time.

Set up a basic html page with linked css and javascript to build a countdown timer, including a date input and a dynamic days, hours, minutes, and seconds display.

Set up html with a linked stylesheet, center the text, and style the countdown timer with coral background, chocolate blocks, white text, and full-width display.

Learn to build a JavaScript countdown timer by selecting and updating page elements with query selectors and ids. Debug with console.log and use local storage to persist the end date.

Learn to use event listeners in JavaScript to respond to end date input changes, prevent default, clear and reset intervals, and start a countdown using the date value from document.

Trigger the countdown by wiring an input change to start clock, passing the end date value. Update the timer every second with time remaining calculations and interval-driven counter updates.

Calculate the time remaining by subtracting the current date from the end date, then convert to days, hours, minutes, and seconds with Math.floor and modulus, and output to HTML.

Update the countdown timer by writing days, hours, minutes, and seconds into the HTML via innerHTML, pad to two digits with slice, and clear the interval when zero.

Store the countdown timer in local storage so the end date persists after refresh, using get item, set item, and converting to a date object for the input.

Review the JavaScript exercise code that builds a countdown timer by selecting DOM inputs, structuring the clock, and updating days, hours, minutes, and seconds. Starts the clock.