如何插入响应式的youtube视频到网站上

Step #1. Get the YouTube Embed Code

• Go to Youtube.
• Find the video you want to use on your website.
• Click on Share >> Embed >> Right click and copy the HTML code.

Step #2. Use the Embed Code

Paste this embed code in your website. It will look similar to this:

    <iframe width="420" height="315" src="http://www.youtube.com/embed/6xisazZX9bA" frameborder="0" allowfullscreen></iframe>

Step #3. Modify the Embed Code

Add a div tag around the embed code. Use the CSS class video-responsive so that your code now looks like this:

<div class="video-responsive">
    <iframe width="420" height="315" src="http://www.youtube.com/embed/6xisazZX9bA" frameborder="0" allowfullscreen></iframe>
</div>

Step #4. Add the CSS

Now add some CSS properties inside one of your stylesheet files:

.video-responsive{
    overflow:hidden;
    padding-bottom:56.25%;
    position:relative;
    height:0;
}
.video-responsive iframe{
    left:0;
    top:0;
    height:100%;
    width:100%;
    position:absolute;
}

Your videos now will be responsive. Try resizing your browser to see it in action.

This same process works for Vimeo videos and any other service that uses an iframe tag.

原文出处：https://www.ostraining.com/blog/coding/responsive-videos/