优化：图库按时间倒序排列并增强移动端触摸交互

styles.css

@@ -239,6 +239,57 @@ body {
     opacity: 1;
 }
 
+/* 移动端触摸设备优化 */
+@media (hover: none) and (pointer: coarse) {
+    /* 在触摸设备上，overlay始终可见但透明度较低 */
+    .image-overlay {
+        opacity: 0.3;
+        background: rgba(0, 0, 0, 0.5);
+    }
+    
+    /* 点击时显示完整overlay */
+    .image-item:active .image-overlay,
+    .image-item.touched .image-overlay {
+        opacity: 1;
+        background: rgba(0, 0, 0, 0.8);
+    }
+    
+    /* 为触摸设备添加点击提示 */
+    .image-item::after {
+        content: "轻触显示操作";
+        position: absolute;
+        bottom: 8px;
+        left: 50%;
+        transform: translateX(-50%);
+        background: rgba(0, 0, 0, 0.7);
+        color: white;
+        padding: 4px 8px;
+        border-radius: 12px;
+        font-size: 12px;
+        opacity: 0.6;
+        pointer-events: none;
+        z-index: 1;
+    }
+    
+    .image-item.touched::after {
+        opacity: 0;
+    }
+}
+
+/* 在小屏幕设备上也应用类似效果 */
+@media (max-width: 768px) {
+    .image-overlay {
+        opacity: 0.4;
+        background: rgba(0, 0, 0, 0.6);
+    }
+    
+    .image-item:active .image-overlay,
+    .image-item.touched .image-overlay {
+        opacity: 1;
+        background: rgba(0, 0, 0, 0.8);
+    }
+}
+
 /* 状态指示器 */
 .status-indicator {
     display: inline-block;
@@ -554,6 +605,40 @@ body {
 .btn-grid-row .btn {
     flex: 1;
     min-width: 0;
+    min-height: 36px;
+    font-size: 14px;
+}
+
+/* 移动端按钮优化 */
+@media (max-width: 768px) {
+    .btn-grid {
+        gap: 8px;
+    }
+    
+    .btn-grid-row {
+        gap: 8px;
+    }
+    
+    .btn-grid-row .btn {
+        min-height: 44px; /* 增加触摸目标大小 */
+        font-size: 16px;
+        padding: 8px;
+    }
+}
+
+/* 触摸设备专用样式 */
+@media (hover: none) and (pointer: coarse) {
+    .btn-grid-row .btn {
+        min-height: 48px; /* 更大的触摸目标 */
+        font-size: 18px;
+        padding: 10px;
+        transition: all 0.2s ease;
+    }
+    
+    .btn-grid-row .btn:active {
+        transform: scale(0.95);
+        opacity: 0.8;
+    }
 }
 
 /* 错误状态 */