change some styling for index and config

Signed-off-by: Arthur Lu <learthurgo@gmail.com>

config.html

@@ -24,7 +24,8 @@
 				</div>
 			</nav>
 		</header>
-		<main class="w3-container">
+		<main>
+			<section class="w3-container">
 				<h2 id="name"><a href="index.html">Instances</a> / %{vmname}</h2>
 				<form>
 					<fieldset>
@@ -43,6 +44,7 @@
 						<button class="w3-button w3-margin" id="exit" type="button">EXIT</button>
 					</div>
 				</form>
+			</section>
 		</main>
 	</body>
 </html>

index.html

@@ -24,13 +24,14 @@
 				</div>
 			</nav>
 		</header>
-		<main class="w3-container">
+		<main>
+			<section class="w3-container">
+				<div class="flex row nowrap" style="justify-content: space-between;">
 					<h2>Instances</h2>
-			<div id="instance-container">
-			</div>
-			<div class="center-div" style="text-align: center;">
-				<img id="instance-add" src="images/actions/instance/add-instance.svg" class="clickable" alt="Create New Instance" title="Create New Instance">
+					<button type="button" id="instance-add" class="w3-button">Create New Instance</button>
 				</div>
+				<div id="instance-container" class="w3-card w3-padding"></div>
+			</section>
 		</main>
 	</body>
 </html>

login.html

@@ -21,8 +21,8 @@
 				</div>
 			</nav>
 		</header>
-		<main class="w3-container w3-display-middle w3-mobile">
-			<div class="w3-card-4 w3-margin w3-container">
+		<main>
+			<div class="w3-card w3-margin w3-container w3-display-middle">
 				<h2 class="w3-center">Proxmox VE Login</h2>
 				<form>     
 					<label for="username"><b>Username</b></label>