Viewport for response layout

Viewport 是個 meta tag，一個虛擬的窗口。
主要是解決不同尺寸不同解析度造成顯示上的差異。
當你設定的頁面尺吋和devices不同，造成跑版的現像。

<meta name=”viewport” content=”width=device-width, initial-scale=1, maximum-scale=1″>

屬性說明
with=devices-width 指定viewport的寛度為devices的寛度

禁止使用者放大縮小

<meta name="viewport" content="user-scalable=0">
<meta name="viewport" content="user-scalable=no">

初始放大比例

<meta name="viewport" content="width=device-width, initial-scale=1.0">

限制放大比例

<meta name="viewport" content="width=device-width, maximum-scale=15.0">

限制縮小比例

<meta name="viewport" content="width=device-width, minimum-scale=0.1">

Reference:
http://developer.apple.com/library/IOS/#documentation/AppleApplications/Reference/SafariWebContent/UsingtheViewport/UsingtheViewport.html

http://webdesignerwall.com/tutorials/viewport-meta-tag-for-non-responsive-design

https://developer.mozilla.org/en-US/docs/Mobile/Viewport_meta_tag

http://www.w3.org/TR/css-device-adapt/#the-viewport