Here is the html, css and js (u gotta flex u can use js when u can) codes for recreating ths website:-
For viewing codes in a clean and a programmer way, heres the link for githhub:
https://github.com/Samyak354/tht_calendar_thingy.github.io
Resources used (maybe useful for you in future projects):-
color picker chrome extension
google (that one time i had to search how to center a div)
Final Result (Close Enough Right??) :

This is gonna be a mess but here is the codes u can ctrl+c and ctrl + v (but pay attention to file names and where u save the files):
HTML
<html>
<head>
<title>Kyalendar ig</title>
<link rel="stylesheet" href="bruhhh.css">
</head>
<body>
<div class="tht_grey_thingy">
<div class="tht_white_thingy">
<center>
<label id="titole">February 2019</label>
<table>
<tr id="dayz">
<td><span>S</span>U</td>
<td><span>M</span>O</td>
<td><span>T</span>U</td>
<td><span>W</span>E</td>
<td><span>T</span>H</td>
<td><span>F</span>R</td>
<td><span>S</span>A</td>
</tr>
<tr id="row-1">
</tr>
<tr id="row-2">
</tr>
<tr id="row-3">
</tr>
<tr id="row-4">
</tr>
</table>
</center>
</div>
<script src="sus.js"></script>
</body>
</html>
CSS
#titole {
color: #344e67;
font—family: Arial, Helvetica, sans-serif;
font-size: 35px;
text-align: center;
font-weight: 630;
}
#dayz {
color: #8ba1b5;
font—family: Arial, Helvetica, sans-serif;
font-size: 20px;
}
span {
color: #8ba1b5;
font—family: Arial, Helvetica, sans-serif;
font-size: 25px;
}
table {
padding: 10px;
border: 3px solid #bdccdb;
border-radius: 10px;
margin-top: 15px;
background-color: white;
}
td {
padding: 10px;
text-align: center;
}
body {
background-color: #d9e2eb;
}
JS
const row_1 = document.querySelector("#row-1")
const row_2 = document.querySelector("#row-2")
const row_3 = document.querySelector("#row-3")
const row_4 = document.querySelector("#row-4")
let a = 1
let b = 8
let c = 15
let d = 22
function render(stort) {
let dates=""
for(let i=stort; i<stort+7; i++) {
dates += `
<td>
${i}
</td>`
}
if(stort==a) {
row_1.innerHTML = dates
}else if(stort==b) {
row_2.innerHTML = dates
}else if(stort==c) {
row_3.innerHTML = dates
}else if(stort==d) {
row_4.innerHTML = dates
}
}
function view() {
render(a)
render(b)
render(c)
render(d)
}
view()