Close registration of the 2024 workshop

pages/community/precice-workshop-2024.md

@@ -23,8 +23,6 @@ Keep watching this space for updates on registration, the workshop program, and
 
 ## Program
 
-Next you find the preliminary program for the workshop. More details will be added in the next weeks, stayed tuned!
-
 The cost of lunch, as well as coffee and snacks is included in the registration fee. The same applies for the invited dinner.
 
 ### Course
@@ -344,6 +342,8 @@ If you are new to preCICE, this is the perfect way to get started. September 24
 
 ## Registration
 
+<details>
+  <summary>The registration period had ended.</summary>
 Registration is open until September 15. Register before July 15 to benefit from early-bird prices!
 
 You can register for the full workshop (talks + course) or for the main part (only talks), in case you already know the topics covered by the course or you cannot attend on the first days.
@@ -370,6 +370,8 @@ In case of cancellations, requests for refunds must be made by July 15, 2024. To
 If you are a holder of a [preCICE suport license](https://precice.org/community-support-precice.html#2-support-license), three members of your organisation are exempt of the registration fee and can register to the workshop by simply writing to [[email protected]](mailto:[email protected]) before the registration deadline.
 {% endnote %}
 
+</details>
+
 ## The venue
 
 The 5th preCICE Workshop will be held in [Pfaffenwaldring 5A](https://maps.app.goo.gl/PmpURsjfKTja19vz8), room 0.009 at the  [Campus Vaihingen](https://www.uni-stuttgart.de/en/university/map/) of the University of Stuttgart. Campus Vaihingen is located between the city district of Vaihingen (easily reachable by bus) and the city center of Stuttgart (15 min away by suburban rail).