fix: 缩小顶部工具栏元素宽度，优化移动端保存图片到相册

css/style.css

@@ -31,7 +31,9 @@ html, body {
 }
 
 .btn {
-    padding: 10px 24px;
+    min-width: 72px;
+    height: 40px;
+    padding: 0 12px;
     font-size: 15px;
     border: 1px solid #ddd;
     border-radius: 6px;
@@ -40,6 +42,9 @@ html, body {
     cursor: pointer;
     transition: all 0.2s;
     white-space: nowrap;
+    display: flex;
+    align-items: center;
+    justify-content: center;
 }
 
 .btn:active {
@@ -47,6 +52,7 @@ html, body {
 }
 
 .btn-primary {
+    min-width: 100px;
     background: #4a90e2;
     color: #fff;
     border-color: #4a90e2;