feat: 实现移动端长按保存图片，删除分享功能

js/script.js

@@ -648,17 +648,101 @@
 
         try {
             const canvas = await generateCanvas();
-
-            const link = document.createElement('a');
-            link.download = '邀请函_' + Date.now() + '.png';
-            link.href = canvas.toDataURL('image/png');
-            link.click();
+            showMobileSaveTip();
         } catch (err) {
             console.error('保存失败:', err);
             alert('保存失败，请重试');
         }
     }
 
+    // 显示移动端保存选项
+    function showMobileSaveTip() {
+        const canvas = exportCanvas;
+        const dataUrl = canvas.toDataURL('image/png');
+        const filename = '邀请函_' + Date.now() + '.png';
+
+        const tipOverlay = document.createElement('div');
+        tipOverlay.id = 'mobileSaveTip';
+        tipOverlay.style.cssText = `
+            position: fixed;
+            top: 0;
+            left: 0;
+            right: 0;
+            bottom: 0;
+            background: rgba(0,0,0,0.6);
+            display: flex;
+            align-items: flex-end;
+            justify-content: center;
+            z-index: 10000;
+        `;
+
+        const savePanel = document.createElement('div');
+        savePanel.style.cssText = `
+            width: 100%;
+            background: #fff;
+            border-radius: 16px 16px 0 0;
+            padding: 20px;
+            padding-bottom: 40px;
+        `;
+
+        const title = document.createElement('p');
+        title.textContent = '保存图片';
+        title.style.cssText = `
+            font-size: 18px;
+            font-weight: bold;
+            text-align: center;
+            margin-bottom: 20px;
+            color: #333;
+        `;
+
+        const saveBtn = document.createElement('button');
+        saveBtn.textContent = '保存到相册';
+        saveBtn.style.cssText = `
+            width: 100%;
+            padding: 16px;
+            font-size: 16px;
+            background: #007AFF;
+            color: #fff;
+            border: none;
+            border-radius: 10px;
+            cursor: pointer;
+            margin-bottom: 12px;
+        `;
+        saveBtn.onclick = () => {
+            tipOverlay.remove();
+            const link = document.createElement('a');
+            link.download = filename;
+            link.href = dataUrl;
+            link.click();
+        };
+
+        const cancelBtn = document.createElement('button');
+        cancelBtn.textContent = '取消';
+        cancelBtn.style.cssText = `
+            width: 100%;
+            padding: 16px;
+            font-size: 16px;
+            background: #F2F2F7;
+            color: #333;
+            border: none;
+            border-radius: 10px;
+            cursor: pointer;
+        `;
+        cancelBtn.onclick = () => tipOverlay.remove();
+
+        tipOverlay.addEventListener('click', (e) => {
+            if (e.target === tipOverlay) {
+                tipOverlay.remove();
+            }
+        });
+
+        savePanel.appendChild(title);
+        savePanel.appendChild(saveBtn);
+        savePanel.appendChild(cancelBtn);
+        tipOverlay.appendChild(savePanel);
+        document.body.appendChild(tipOverlay);
+    }
+
     // 窗口大小改变时更新图片位置和边界
     window.addEventListener('resize', () => {
         if (currentImage) {