How is the winning number generated?The winning number is chosen using the
PHP function random_int, according to the PHP manual the random_int function "Generates cryptographic random integers that are suitable for use where unbiased results are critical, such as when shuffling a deck of cards for a poker game.".
I was thinking of using other methods like entering a manual random seed, but apart from complicating the project, it would not increase the randomness and could be considered that the result has been manipulated. In the end, it was decided that the winner is chosen by the computer alone without human intervention.
We have no objection to your way of generating randomness, but to the fact that your system is not provably fair. What's stopping you from drawing the numbers until you get a result that works in your favor? All of this can be done in the background in a fraction of a second and players have no way to verify that the draw was fair and unbiased. Learn what provably fair systems mean.
Why the website has this design?
The website has been designed from scratch and there is no desire to use third party libraries.
Regarding the look and feel, it's just a personal preference, I like the Windows look and feel of the late 90's and early 20th century, for it's ease of reading. I also like the gray and blue tones in the theme to give it a business and serious look.
Yes, it's a personal preference, but the primary purpose of design is to sell a product. Does your design sell a product? Besides, you don't have to compromise on speed to have a beautifully designed site. Websites can be both lightweight and attractive at the same time.