feat(界面设计): 精简设置布局，修正标题栏遮罩

assets/webui/index.html

@@ -455,7 +455,6 @@
 					</nav>
 					<div class="appearance-content">
 						<section data-appearance-page="theme">
-							<div class="appearance-label">外观主题</div>
 							<div class="appearance-themes">
 								<button type="button" data-theme-choice="system"><span class="theme-system-icon"></span><span>系统</span></button>
 								<button type="button" data-theme-choice="light"><span class="theme-light-icon"></span><span>浅色</span></button>
@@ -463,7 +462,6 @@
 							</div>
 						</section>
 						<section id="associationSection" data-appearance-page="association" hidden>
-							<div class="appearance-label">文件关联</div>
 							<div class="association-row" data-scope="user"><span>当前用户</span><span class="association-state"></span><div class="association-actions"><button class="small-button" type="button" data-action="register">注册</button><button class="small-button" type="button" data-action="remove">撤销</button></div></div>
 							<div class="association-row" data-scope="machine"><span>所有用户</span><span class="association-state"></span><div class="association-actions"><button class="small-button" type="button" data-action="register">注册</button><button class="small-button" type="button" data-action="remove">撤销</button></div></div>
 							<div id="associationMessage" class="form-status" hidden></div>

assets/webui/ofdgo.css

@@ -4846,10 +4846,6 @@ audio.page-media {
 	padding: 0;
 }
 
-.appearance-dialog::backdrop {
-	top: 0;
-}
-
 .appearance-heading {
 	display: flex;
 	align-items: center;
@@ -4891,7 +4887,7 @@ audio.page-media {
 
 .appearance-content {
 	min-width: 0;
-	padding: 20px;
+	padding: 12px 16px;
 	overflow-y: auto;
 }
 
@@ -4907,20 +4903,11 @@ audio.page-media {
 		border-right: 0;
 		border-bottom: 1px solid var(--line);
 	}
-	.appearance-content {
-		padding: 16px;
-	}
 	.appearance-dialog .association-row {
 		gap: 8px;
 	}
 }
 
-.appearance-label {
-	font-size: 12px;
-	color: var(--text-muted);
-	margin-bottom: 12px;
-}
-
 .appearance-themes {
 	display: flex;
 	gap: 3px;