I'm only getting the latest date as dataframe, rather than all…?

I’m using the below code to scrape several tables across multiple dates. The code works well, but the output when saving to CSV only stores the latest data as a dataframe.

What am I missing here in order to union / concatenate all these scraped dates into one dataframe?

##### import packages #######
import requests
from bs4 import BeautifulSoup
import pandas as pd
from datetime import datetime
import re
#############################

years = ["2023"]
weeks = list(range(1, 5)) # Weeks should probably range from 1 to 53, since rarely there can be 53 instead of 52 weeks in a year

urls = [f"https://www.debestseller60.nl/{year}{week:02}#top" for year in years for week in weeks]

### set user-agent #### 
## response = requests.get(url,headers={'user-agent':'Mozilla/5.0'})

for url in urls:
    response = requests.get(url)
    if response.status_code == 200:
        soup = BeautifulSoup(response.content, "html.parser")

        # Your scraping logic here
        data = []

        cards = soup.find_all("div", class_="card")

        for book in cards:
            author = book.find("div", class_="card__author").text.strip() if book.find("div", class_="card__author") else None
            title = book.find("div", class_="card__title heading-2 mb-2 clickable").text.strip() if book.find("div", class_="card__title heading-2 mb-2 clickable") else None 
            Hebban_link = book.find("y-use", class_="History").text.strip() if book.find("y-use", class_="History") else None 
            for card in cards:
                tags_div = card.find('div', class_='card__tags')
                if tags_div is not None:
                    tags = tags_div.find_all('div', class_='card__tags__tag')
                    if len(tags) >= 4:
                        tag = tags[-2].text.strip()
                    else:
                        tag = tags[-1].text.strip()
                else:
                    tag = "No tags found for this card"

            # find the div element with the class "weeks__week week week--active"
            active_week_div = soup.find('div', class_='weeks__week week week--active')

            # print the text content of the div element
            print(active_week_div.text.strip())

            #append data
            data.append({"Author": author, "Title": title, "Hebban_link": Hebban_link,"ISBN": tag, "week_year":active_week_div.text.strip()})

            #convert to dataframe
            df = pd.DataFrame(data)

            ## add rank
            df["rank"] = df.index + 1

            print(df)


            data.append(df)

else:
                print(f"Failed to fetch data for URL: {url}")

#converted a file to csv
pd.concat(data).to_csv("top60.csv", encoding='utf-8', index=False)