Add disconnection and minor improvements on login page.

frontend/src/app/pages/login/login.component.scss

@@ -0,0 +1,37 @@
+:host {
+    display: flex;
+    flex-direction: column;
+    justify-content: center;
+    align-items: center;
+
+    form {
+        min-width: 40em;
+        max-width: 90%;
+        display: flex;
+        flex-direction: column;
+        justify-content: center;
+        gap: .5em;
+
+        div {
+            display: flex;
+            gap: .5em;
+
+            &.actions {
+                justify-content: end;
+
+                button {
+                    width: 10em;
+                    height: 2em;
+                }
+            }
+
+            label {
+                flex: 1 30%;
+            }
+
+            input {
+                flex: 1 70%;
+            }
+        }
+    }
+}