If you have an element around it like so:
Code:
<div class="gallery-container">
<select class="gallery-select"
onchange="document.getElementById('galleryimg').src = this.options[this.selectedIndex].value;">
<option value="car.jpeg" selected>Car</option>
<option value="/images/cat.png">Cat</option>
<option value="http://www.example.com/dog.gif">Dog</option>
</select>
<img id="gallery-image" src="car.jpeg">
</div>
Then you can style it like so:
Code:
.gallery-select, #gallery-image {
display: block;
text-align: center;
}
.gallery-container {
text-align: center;
}
As for your site: it doesn't conform to the DOCTYPE you gave it, but you'd probably be better off with HTML Strict anyway. Inline CSS is generally a bad idea because you lose the caching and maintenance benefits of the content–presentation separation CSS provides; you should make it external (put it in a separate text file with a .css extension, and add a link to it in your <head>: <link type="text/css" rel="stylesheet" href="/path/to/stylesheet.css">; use classes and IDs to specify which elements to style, as I've done above). Verdana is a bad choice for Web fonts, and whatever specific font you choose, make sure to provide a generic font family in case the user doesn't have that font (you don't want it reverting to monospace or something), e.g. font-family: Verdana, sans-serif;.
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