修改本地视频类型判断

docs/thumbnail/css/common.css

@@ -38,6 +38,7 @@ html, body {
     height: 300px;
     border: 2px dashed #d9d9d9;
     text-align: center;
+    font-size: 16px;
     cursor: pointer;
     border-radius: 3px;
     margin-bottom: 10px;

docs/thumbnail/index.html

@@ -19,7 +19,7 @@
     <div class="container">
         <div class="left-part">
             <div class="upload">
-                Click to upload video file, support format: mp4, ogg, webm
+                Drop video file here or click to upload.
                 <input class="file" type="file">
             </div>
             <div class="artplayer"></div>