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# padding color

參考文章:(<https://stackoverflow.com/questions/14628601/can-i-add-background-color-only-for-padding>)

以我的例子來說，我用jQuery 畫出 QRcode 會長這樣

![](/files/-LmbdtZPOrfuz3flBNU8)

假如背景是更深一點，甚至是黑色，會導致 QRcode 不容易被使用者掃描，所以我希望在外圍增加白色邊框。 那個canvas 是jQuery 畫出QRcode 的元素

*style*

```
.QRCODE_pic canvas{
    text-align: center;
    width:36em;
    height:36em;
    padding:1em;
    box-shadow: inset 0 0 0 1em white;
}
```

*jQuery*

```
$("div[data-role=QRCode]").qrcode({ width:512, height:512, text : "123" });
```

*html*

```
<div class="QRCODE_pic" data-role="QRCode"></div>
```

![](/files/-LmbdtZSFdLwVnBNj-xO)

這是我畫出來的效果，希望有幫助囉。


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