diff --git a/index.php b/index.php
index 5d905cf..6b87056 100644
--- a/index.php
+++ b/index.php
@@ -1,31 +1,29 @@
 <?php
-    $ago = '0'; // 时间 (几天前。0为今天，1为昨天，2为前天，以此类推。)
-    $region = '1'; // 位置（必应国际版填0，国内版填1。）
-    // 必应国内版当日16至次日16时为一张壁纸。
+// GitHub: https://github.com/zhxycn/BingWallpaperAPI
+$ago = '0';  //How many days ago
+$region = '0';  //Bing region
 
-    if ($_GET['region'] == 'global') {
-        $region = '0';
-    } elseif ($_GET['region'] == 'cn') {
-        $region = '1';
-    } else {
-        $region = $region;
-    }
-
-    if ($region == '0') {
-        $data = json_decode(file_get_contents('https://bing.com/HPImageArchive.aspx?format=js&idx='.$ago.'&n=1'), true); 
-        $url = "https://bing.com".$data['images'][0]['url']; 
-    } elseif ($region == '1') {
-        $data = json_decode(file_get_contents('https://cn.bing.com/HPImageArchive.aspx?format=js&idx='.$ago.'&n=1&mkt=zh-CN'), true); 
-        $url = "https://cn.bing.com".$data['images'][0]['url']; 
-    }
-    
-    $date = $data['images'][0]['startdate'];
-    $copyright = $data['images'][0]['copyright'];
-
-    if ($_GET['encode'] == 'json') {
-    	$echo = array('date' => $date, 'url' => $url, 'copyright' => $copyright);
-        echo json_encode($echo);
-    } else {
-        header("Location:$url"); 
-    }
+$ago = $_REQUEST['ago'];
+if ($_REQUEST['region'] == 'global') {
+    $region = '0';
+} elseif ($_REQUEST['region'] == 'cn') {
+    $region = '1';
+} else {
+    $region = $region;
+}
+if ($region == '0') {
+    $data = json_decode(file_get_contents('https://bing.com/HPImageArchive.aspx?format=js&idx=' . $ago . '&n=1'), true);
+    $url = "https://bing.com" . $data['images'][0]['url'];
+} elseif ($region == '1') {
+    $data = json_decode(file_get_contents('https://cn.bing.com/HPImageArchive.aspx?format=js&idx=' . $ago . '&n=1&mkt=zh-CN'), true);
+    $url = "https://cn.bing.com" . $data['images'][0]['url'];
+}
+$date = $data['images'][0]['startdate'];
+$copyright = $data['images'][0]['copyright'];
+if ($_REQUEST['encode'] == 'json') {
+    $echo = array('date' => $date, 'url' => $url, 'copyright' => $copyright);
+    echo json_encode($echo);
+} else {
+    header("Location:$url");
+}
 ?>