Use css for darkmode

templates/chat/chat_css.html

@@ -99,19 +99,6 @@
         padding: 0.05em 0.6em;
         width: 100%;
     }
-    .active-span {
-        margin-top: 1em;
-        margin-right: 1em;
-        color: #636363;
-    }
-
-    .unread-count {
-        float: right;
-        color: white;
-        background-color: darkcyan;
-        border-radius: 2px;
-        padding: 0 0.5em;
-    }
     #search-form {
         float: inherit;
     }
@@ -121,26 +108,7 @@
     #setting {
         position: relative;
     }
-    #setting-content {
-        display: none;
-        position: absolute;
-        background-color: #f1f1f1;
-        min-width: 160px;
-        box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
-        z-index: 1;
-        right: 0;
-    }
-    #setting-content li {
-        padding: 12px 16px;
-        text-decoration: none;
-        display: block;
-        color: black;
-        font-weight: bold;
-    }
-    #setting-content li:hover {
-        background-color: #ddd;
-        cursor: pointer;
-    }
+    
 
     @media (min-width: 800px) {
         #page-container {