What functions I used in this page:
- Hide some elements -> 'hidden' class in HTML, 'display: none' in CSS, and they are controled in Javascript
- Prevent page refresh after submit of input tag -> use preventDefault()
- Save my(user) name -> use browser's localStorage
- Create a clock -> use Date(), padStart()
- Create a img tag in HTML -> Display three random background images using Math.random()
- Create a span tag in HTML -> Display ten random quotes using Math.random()
- Create a to-do list -> save/load an array to localStorage, delete an element of array and save, some JSON convert
- Get a weather from my location -> use weather API from openweathermap, fetch weather, temperature, and city name