JSFiddle - React, Tailwind, and code Playground

by ibasoglu

HTML

<input type="text" value="deger" pattern="[1-9]{1}[0-9]{3}">
Kural 4 basamaklı bir sayı giriniz.

CSS

input:valid {
    border: 1px solid green;
}

input:invalid {
    border: 1px solid red;
}