implemented theme changer

web/src/main/resources/web/css/winter.css

@@ -0,0 +1,37 @@
+a {
+    color: black;
+}
+body {
+    background: white;
+    color: navy;
+}
+
+fieldset {
+    border: 1px solid blue;
+    border-radius: 4px;
+}
+
+input{
+    background: lightcyan;
+    border: 1px dotted blue;
+    border-radius: 4px;
+    padding: 3px;
+    margin: 3px;
+    color: blue;
+}
+
+button{
+    background: red;
+    border-radius: 5px;
+    padding: 5px 7px;
+    border-width: 2px;
+    border-style: solid;
+    border-color: yellow red red yellow;
+}
+footer {
+  position: absolute;
+  bottom: 0;
+  width: 100%;
+  text-align: center;
+  margin: 5px;
+}

web/src/main/resources/web/themes.json

@@ -0,0 +1,13 @@
+[
+  {
+    "value"   : "winter",
+    "caption" : "Winter"
+  },
+  {
+    "value" : "bloodshed"
+  },
+  {
+    "value" : "default",
+    "caption": "default"
+  }
+]