use REMARK_URL in frontend templates

frontend/comments.ejs

@@ -68,7 +68,7 @@
 
         var remark_config = {
           site_id: query.site_id,
-          host: window.location.origin,
+          host: '<%= REMARK_URL %>' || window.location.origin,
           url: query.url
         };
 

frontend/counter.ejs

@@ -39,7 +39,7 @@
   <script>
     var remark_config = {
       site_id: 'remark',
-      host: window.location.origin,
+      host: '<%= REMARK_URL %>' || window.location.origin,
       url: 'https://remark42.com/demo/',
       components: ['counter']
     };

frontend/index.ejs

@@ -123,7 +123,7 @@
 
       var remark_config = {
         site_id: 'remark',
-        host: window.location.origin,
+        host: '<%= REMARK_URL %>' || window.location.origin,
         url: 'https://remark42.com/demo/',
         components: ['embed', 'counter'],
         // __colors__: {

frontend/last-comments.ejs

@@ -25,7 +25,7 @@
     <script>
       var remark_config = {
         site_id: 'remark',
-        host: window.location.origin,
+        host: '<%= REMARK_URL %>' || window.location.origin,
         components: ['last-comments']
       };
 

frontend/webpack.config.js

@@ -180,21 +180,33 @@ module.exports = () => ({
     new Html({
       template: path.resolve(__dirname, 'index.ejs'),
       inject: false,
+      templateParameters: {
+        REMARK_URL: remarkUrl,
+      },
     }),
     new Html({
       template: path.resolve(__dirname, 'counter.ejs'),
       filename: 'counter.html',
       inject: false,
+      templateParameters: {
+        REMARK_URL: remarkUrl,
+      },
     }),
     new Html({
       template: path.resolve(__dirname, 'last-comments.ejs'),
       filename: 'last-comments.html',
       inject: false,
+      templateParameters: {
+        REMARK_URL: remarkUrl,
+      },
     }),
     new Html({
       template: path.resolve(__dirname, 'comments.ejs'),
       filename: 'comments.html',
       inject: false,
+      templateParameters: {
+        REMARK_URL: remarkUrl,
+      },
     }),
     new MiniCssExtractPlugin({
       filename: '[name].css',