CSS: resizing logo while maintaining aspect with browser

#logo {
    background: url(/images/logo.png) 0 0 no-repeat;
    width: 268px;
    height: 96px;
    position: fixed;
    top: 10px;
    left: 10px;
    z-index: 1000;
}

This is my logo css and w开发者_JS百科hen I change the height and width to x% It just cuts of the bottom and right side of my logo image. How can I style my logo so that it stays at 5% of the browser width while maintaining aspect? Thanks

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Your image has to be an <img> tag, not a background, and the CSS of this <img> tag :

#logo_img{
    width:5%;
}

assuming the parent of #logo_img is 100% in width.

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By using the <img> element for images, of course.

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It is possible in a background image. See this demo at CSSplay. Ethan Marcotte has also detailed techniques that may fit your application.