Transparent png image is not fully transparent in browser
===

I am using chrome browser. I have a fully transparent png image for logo. But there seems to be a problem:

![enter image description here][1]

You need to look quite a second time but as you can see the image has a lighter tint than the background. I create the background with css:

       background: #e1e2e4;
        background: -webkit-gradient(linear, left top,
        left bottom, from(#e1e2e4), to(#8f9094));

        background: -moz-linear-gradient(top,  #e1e2e4,  #8f9094);
        filter:  progid:DXImageTransform.Microsoft.gradient
        (startColorstr='#e1e2e4', endColorstr='#8f9094'); 
    	
        background-repeat: no-repeat;
        background-attachment: fixed;

Any ideas why this happens? How can I solve this?

  [1]: http://i.stack.imgur.com/CR4C5.png