add color theme option

settings.html

@@ -6,6 +6,7 @@
 		<title>proxmox - dashboard</title>
 		<link rel="icon" href="images/favicon.svg" sizes="any" type="image/svg+xml">
 		<link rel="stylesheet" href="w3.css">
+		<link rel="stylesheet" href="https://www.w3schools.com/w3css/4/w3.css">
 		<link rel="stylesheet" href="css/style.css">
 		<link rel="stylesheet" href="css/nav.css">
 		<link rel="stylesheet" href="css/form.css">
@@ -75,6 +76,19 @@
 							<p>Sorts by best matching to worst matching.</p>
 						</fieldset>
 					</div>
+					<div class="w3-card w3-padding">
+						<h3>Appearance</h3>
+						<fieldset>
+							<label>
+								Theme
+								<select class="w3-select w3-border" id="appearance-theme" name="appearance-theme" style="width: fit-content; padding-right: 24px;">
+									<option value="auto">Auto</option>
+									<option value="dark">Dark</option>
+									<option value="light">Light</option>
+								</select>
+							</label>
+						</fieldset>
+					</div>
 					<div class="w3-container w3-center" id="form-actions">
 						<button class="w3-button w3-margin" id="save" type="submit">SAVE</button>
 					</div>