Updated README

README.md

@@ -144,3 +144,45 @@ Add client credentials to `appsettings.json` (or via environment / user-secrets)
 ## Licence
 
 This project is provided as-is for personal use.
+## Using Custom SSL Certificates
+
+To enable HTTPS with custom SSL certificates in your Blazor application, follow these steps:
+
+1. **Prepare PEM Files**
+   Place your certificate and private key files in PEM format in a directory accessible by your app.
+   Example paths:
+   - `/app/data/certs/cert.pem`
+   - `/app/data/certs/key.pem`
+
+2. **Configure Certificate Paths**
+   The application will look for certificate files in the following order:
+   - Environment variables: `PEM_CERT_FILE` and `PEM_KEY_FILE`
+   - Configuration values: `PemCertFile` and `PemKeyFile` in `appsettings.json`
+   - Default: `/app/data/certs/cert.pem` and `/app/data/certs/key.pem`
+
+   You can set environment variables before running the app:
+   ```bash
+   export PEM_CERT_FILE=/path/to/cert.pem
+   export PEM_KEY_FILE=/path/to/key.pem
+   ```
+
+   Or add to your `appsettings.json`:
+   ```json
+   {
+     "PemCertFile": "/path/to/cert.pem",
+     "PemKeyFile": "/path/to/key.pem"
+   }
+   ```
+
+3. **Fallback Behavior**
+   If the certificate files are not found, the app will use the default development certificate.
+
+4. **No Code Changes Needed**
+   The certificate loading logic is already implemented in `Program.cs`. Simply provide the files and configuration as described above.
+
+---
+
+**Note:**
+- Certificates must be in PEM format (`.pem`).
+- Ensure file permissions allow the app to read the certificate and key files.
+- For production, use certificates issued by a trusted Certificate Authority.