V-3 Chessboard Illusion

GDPR: the new European directive on the processing and protection of personal data.

For more information about the GDPR, please visit the official GDPR website.

We use cookies on our website to ensure a better user experience.

What are cookies?

Cookies are small text files that are automatically stored on your computer, tablet or mobile phone when you visit a website.
They are essential for the proper functioning of the site.

Can you use cookies to find out who I am?

We don’t retain your name, address, age and other personal data.
Your data will only be kept for purposes such as responding to the submission of a form.

Are cookies safe?

A cookie cannot do any harm and has nothing to do with computer viruses or other Internet threats.

How long are cookies stored for?

We use temporary cookies and cookies that remain on your computer for longer.
The length of time a cookie stays on your computer depends on the type of cookie.
A temporary cookie is automatically deleted when you close your browser.

Do cookies slow down your computer?

No, cookies don’t take up extra memory on your computer or slow it down.

What happens if I accept cookies?

We will then install cookies that ensure the website works optimally.
Only if you accept cookies will you receive one that allows you to watch videos.
Our cookies also enable you to log in and us to keep anonymous data on your visit in the form of statistics.

Can I change the cookie settings after I have accepted cookies? 

You can change your own cookie settings whenever you want.

Website statistics and Website tools ?

We use tracking cookies to gather more information about how the website is used.

These cookies are not disabled, but the data are processed anonymously, and the possibility of sharing data is disabled.

Other Google services are not used in combination with Google Analytics cookies.


In order to ensure the proper functioning of the website, the platform only uses cookies such as a cookie for storing logged-in sessions (this only applies to administrators).

None of these cookies contain personal information or are used to monitor the user.

Management of Cookies ?

You can allow, block or delete the cookies installed on your computer by configuring the browser options installed on your computer.

• Google Chrome:

1. Click on the menu icon.
2. Select "configuration".
3. Select "advanced configuration".
4. Select "privacy."
5. Select "content configuration".
6. Select the function you want:
7. Allow local data to be stored.
8. Keep local data only until you exit the browser.
9. Do not allow data to be saved from the sites.
10. block data from third-party sites and cookies.
11. Once the desired option is selected, click on "ready".

• Internet Explorer:

1. Click on the "start" icon.
2. Select "internet options" in the "tools" menu.
3. Select "privacy."
4. Select "configuration".
5. Select the option you want and click on "Accept".

• Microsoft Edge (Explorer 10):

1. Click on the "more" icon.
2. Select "configuration".
3. Select "advanced configuration".
4. Select "cookies" within "Privacy and services".
5. Select the option you want from the drop-down menu.

• Firefox:

1. Click on the "menu" icon.
2. Select "options."
3. Select "privacy."
4. Select the option you want from the drop-down menu.

• Safari:

1. Click on "safari".
2. Select "preferences."
3. Select "privacy."
4. Select "cookies and website data".
5. Select the option you want among the available ones.

You must take into account that if you delete or block all cookies on this Website, it is possible that part of it may not work properly or the quality of the Website may be affected.