update

zhangyonghong · zhangyonghong · commit 895846529fbc · 2015-09-28T10:59:41.000+08:00
diff --git a/css.md b/css.md
@@ -311,4 +311,27 @@ user-select:none;
 <!--移动web页面自动探测电话号码-->
 <meta name="format-detection" content="telephone=no">
 <meta http-equiv="x-rim-auto-match" content="none">
+```
+
+- [CSS判断横屏竖屏](http://www.w3cways.com/1772.html)
+```css
+@media screen and (orientation: portrait) {
+  /*竖屏 css*/
+} 
+@media screen and (orientation: landscape) {
+  /*横屏 css*/
+}
+```
+
+```javascript
+//判断手机横竖屏状态：
+window.addEventListener("onorientationchange" in window ? "orientationchange" : "resize", function() {
+        if (window.orientation === 180 || window.orientation === 0) { 
+            alert('竖屏状态！');
+        } 
+        if (window.orientation === 90 || window.orientation === -90 ){ 
+            alert('横屏状态！');
+        }  
+    }, false); 
+//移动端的浏览器一般都支持window.orientation这个参数，通过这个参数可以判断出手机是处在横屏还是竖屏状态。
 ```
