优化界面；修复异常

templates/assets/js/app.js

@@ -2522,15 +2522,55 @@ function initializeMomentFold() {
 // 更换背景函数封装
 function setFixedBackground(bgImageUrl) {
     const body = document.body;
+    const requestId = (Number(body.dataset.backgroundRequestId) || 0) + 1;
+    body.dataset.backgroundRequestId = requestId;
+
+    // 传入空值时淡出并清除当前背景。
+    if (bgImageUrl == null || String(bgImageUrl).trim().toLowerCase() === 'null' || String(bgImageUrl).trim() === '') {
+        body.querySelectorAll('.fixed-background-layer').forEach((layer) => {
+            layer.classList.remove('is-visible');
+            setTimeout(() => layer.remove(), 650);
+        });
+        body.classList.remove('common-fixed-bg');
+        return;
+    }
+
+    const image = new Image();
+    image.onload = async () => {
+        if (typeof image.decode === 'function') {
+            try { await image.decode(); } catch (_) { }
+        }
+
+        if (body.dataset.backgroundRequestId !== String(requestId)) return;
+
+        const backgroundLayer = document.createElement('div');
+        backgroundLayer.className = 'fixed-background-layer';
+        backgroundLayer.style.backgroundImage = `url('${bgImageUrl}')`;
+        body.appendChild(backgroundLayer);
+
+        // 先应用透明状态，再切换到可见状态，确保每次调用都触发淡入。
+        backgroundLayer.offsetWidth;
+        requestAnimationFrame(() => backgroundLayer.classList.add('is-visible'));
+
+        body.querySelectorAll('.fixed-background-layer:not(:last-child)').forEach((layer) => {
+            layer.classList.remove('is-visible');
+            setTimeout(() => layer.remove(), 650);
+        });
+    };
+
     body.classList.add('common-fixed-bg');
-    body.style.backgroundImage = `url('${bgImageUrl}')`;
+    image.src = bgImageUrl;
 }
 
 // 奇遇显示函数封装
-function showCenterImage(imageUrl) {
+function showCenterImage(imageUrl, duration = 2000) {
     const container = document.getElementById('centerImgContainer');
     const img = document.getElementById('targetImg');
 
+    // 清理上一次调用遗留的自动关闭定时器。
+    clearTimeout(container._centerImageCloseTimer);
+    clearTimeout(container._centerImageResetTimer);
+
     // 重置所有状态（避免上一次操作残留影响）
     container.classList.remove('container-fade-active');
     img.classList.remove('img-fade-in', 'img-fade-out');
@@ -2547,15 +2587,17 @@ function showCenterImage(imageUrl) {
         container.classList.add('container-fade-active');
         img.classList.add('img-fade-in');
 
-        // 图片显示1.5秒后，执行自动关闭逻辑
-        setTimeout(() => {
+        // duration 为 0 时保持显示，不执行自动关闭逻辑。
+        if (duration <= 0) return;
+
+        container._centerImageCloseTimer = setTimeout(() => {
             container.classList.remove('container-fade-active');
             img.classList.add('img-fade-out');
 
-            setTimeout(() => {
+            container._centerImageResetTimer = setTimeout(() => {
                 img.classList.remove('img-fade-in', 'img-fade-out');
             }, 500);
-        }, 1500);
+        }, duration);
     }
 
     // 定义图片加载失败的回调函数
@@ -2601,7 +2643,7 @@ function anian_renderLunarUI() {
 
         textEl.innerHTML = text;
 
-        if (jieqi === '大寒') showCenterImage('/upload/qiyu-jieqi-dahan.png');
+        if (jieqi) showCenterImage('/upload/' + jieqi + '.webp');
         // setFixedBackground('/upload/JX3WJ.mp4_20260207_022345.027.jpg');
     };