Update Dockerfile

Dockerfile

@@ -1,8 +1,20 @@
-# Use the official itzg/minecraft-server image
-FROM itzg/minecraft-server:latest
+# Step 1: Start from a clean Java 21 environment
+FROM eclipse-temurin:21-jre-jammy
 
-# You MUST accept the EULA to run the server
-ENV EULA=TRUE
+# Step 2: Set the working directory for our server files
+WORKDIR /server
 
-# Force Java to use a small amount of memory
-ENV JVM_OPTS="-Xms256M -Xmx512M"
+# Step 3: Download the official Minecraft server (version 1.21)
+# NOTE: This download link is for the latest version as of this writing.
+RUN apt-get update && apt-get install -y wget && \
+    wget https://piston-data.mojang.com/v1/objects/450698d1863ab5180c25d7c804ef0fe6369dd1ba/server.jar
+
+# Step 4: Accept the Minecraft EULA
+RUN echo "eula=true" > eula.txt
+
+# Step 5: Expose the default Minecraft port
+EXPOSE 25565
+
+# Step 6: Start the server directly, with full control over memory.
+# We are forcing it to start with 512MB and use a maximum of 1GB of RAM.
+CMD ["java", "-Xms512M", "-Xmx1G", "-jar", "server.jar", "nogui"]