diff --git a/keycloak/how-to-custom-theme.md b/keycloak/how-to-custom-theme.md
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+# Install by Docker
+
+```
+docker run -p 8080:8080 \
+-e KEYCLOAK_ADMIN=admin \
+-e KEYCLOAK_ADMIN_PASSWORD=admin \
+--name keycloak \
+--rm \
+quay.io/keycloak/keycloak:22.0.3 start-dev --spi-theme-static-max-age=-1 --spi-theme-cache-themes=false --spi-theme-cache-templates=false
+```
+
+# Add Theme
+
+```
+docker exec -i keycloak sh <<EOF
+mkdir -p /opt/keycloak/themes/treetracker/login
+cd /opt/keycloak/themes/treetracker/login
+
+# login
+cat <<EO2 > theme.properties
+parent=keycloak
+import=common/keycloak
+styles=web_modules/@fontawesome/fontawesome-free/css/icons/all.css web_modules/@patternfly/react-core/dist/styles/base.css web_modules/@patternfly/react-core/dist/styles/app.css node_modules/patternfly/dist/css/patternfly.min.css node_modules/patternfly/dist/css/patternfly-additions.min.css css/login.css css/treetracker.css
+EO2
+
+mkdir -p resources/css
+cat <<EO3 > resources/css/treetracker.css
+.login-pf body {
+  /*background: url(https://treetracker-production-images.s3.eu-central-1.amazonaws.com/2023.09.23.14.04.00_0.45559833333333327_109.32892366666664_5e5b8f08-2f3f-46f7-adbe-967030e48266_IMG_20230829_091903_642222451085378253.jpg) no-repeat center center fixed;*/
+  background: url(https://treetracker-production-images.s3.eu-central-1.amazonaws.com/2023.04.21.03.36.20_8.485640049999999_-13.254117873333334_27928e01-6f29-4ac0-bee2-df494f3a1363_IMG_20230412_170116_1704432758494134189.jpg) no-repeat left 35%;
+  background-size: cover;
+}
+
+div.kc-logo-text {
+  /*background-image: url(https://map.treetracker.org/images/treetracker_logo.svg);*/
+  background-image: url(https://map.treetracker.org/images/treetracker_logo_white.svg);
+}
+
+:root {
+  --pf-global--primary-color--100: #86C232;
+  --pf-global--primary-color--200: #a6dc5a;
+  --pf-global--primary-color--dark-100: #86C232;
+  --pf-global--primary-color--light-100: #a6dc5a;
+  --pf-global--active-color--100: #68a119;
+  --pf-global--active-color--200: #b9ef6d;
+  --pf-global--active-color--300: #89e00f;
+  --pf-global--active-color--400: #80aa44;
+  --pf-global--link--Color: #61901f;
+  --pf-global--link--Color--hover: #547722;
+  --pf-global--link--Color--light: #b4ef62;
+  --pf-global--link--Color--light--hover: #b7e973;
+  --pf-global--link--Color--dark: #679822;
+  --pf-global--link--Color--dark--hover: #5e9413;
+  --pf-global--default-color--100: #86C232;
+  --pf-global--default-color--200: #a6dc5a;
+  --pf-global--default-color--300: #86C232;
+}
+
+@media (max-width: 767px) {
+    .login-pf-page .card-pf {
+        margin-left: 20px;
+        margin-right: 20px;
+    }
+}
+EO3
+
+mkdir -p resources/js
+cat <<EO4 > resources/js/treetracker.js
+alert("Hello World!");
+EO4
+
+echo "Done!"
+EOF