Title: CSS Validation
Last modified: August 20, 2016

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# CSS Validation

 *  [brett cairns](https://wordpress.org/support/users/brett-cairns/)
 * (@brett-cairns)
 * [13 years, 3 months ago](https://wordpress.org/support/topic/css-validation-1/)
 * Lightbox plugin is great but CSS does not validate – returns 4 errors because
   of filter: progid:DXImageTransform.Microsoft.gradient(startColorstr=#00FFFFFF,
   endColorstr=#00FFFFFF);
 * filter: ~”progid:DXImageTransform.Microsoft.gradient(startColorstr=’#00FFFFFF’,
   endColorstr=’#00FFFFFF’)”; only returns one error but still will not validate
 * Is the use of this proprietary Microsoft filter for IE necessary for the plugin
   to work?
 * thanks
 * [http://wordpress.org/extend/plugins/lightbox-plus/](http://wordpress.org/extend/plugins/lightbox-plus/)

The topic ‘CSS Validation’ is closed to new replies.

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 * 0 replies
 * 1 participant
 * Last reply from: [brett cairns](https://wordpress.org/support/users/brett-cairns/)
 * Last activity: [13 years, 3 months ago](https://wordpress.org/support/topic/css-validation-1/)
 * Status: not resolved