删除分屏选项：移除 HTML 控件、JS 函数、CSS 规则

public/css/chat.css

@@ -207,20 +207,6 @@ a:hover {
     flex: 0.6;
 }
 
-/* 分屏模式下两个窗格各占一半 */
-.message-panes.split-h .message-pane.say1,
-.message-panes.split-h .message-pane.say2 {
-    flex: 1;
-}
-
-.message-panes.split-h .message-pane.say2 {
-    flex: 1;
-}
-
-.message-panes.split-h .message-pane.say1 {
-    flex: 1;
-    border-bottom: 2px solid var(--border-blue);
-}
 
 /* 消息行样式 */
 .msg-line {
@@ -865,8 +851,7 @@ a:hover {
     .input-row label:has(#action),
     .input-row label:has(#font_color),
     .input-row label:has(#font_size_select),
-    .input-row label:has(#sound_muted),
+    .input-row label:has(#sound_muted) {
-    .input-row label:has(#split_screen) {
         display: none !important;
     }
 }

resources/views/chat/partials/layout/input-bar.blade.php

@@ -70,12 +70,6 @@
                 滚屏
             </label>
 
-            <label>分屏:
-                <select id="split_screen" onchange="changeSplitScreen(this.value)">
-                    <option value="0">单窗</option>
-                    <option value="1">上下分</option>
-                </select>
-            </label>
 
             @if (
                 $user->user_level >= (int) \App\Models\Sysparam::getValue('level_announcement', '10') ||

resources/views/chat/partials/scripts.blade.php

@@ -115,15 +115,6 @@
             });
     }
 
-    // ── 分屏切换 ──────────────────────────────────────
-    function changeSplitScreen(mode) {
-        const panes = document.getElementById('message-panes');
-        if (mode === '1') {
-            panes.classList.add('split-h');
-        } else {
-            panes.classList.remove('split-h');
-        }
-    }
 
 
     // ── 动作选择 ──────────────────────────────────────