How to remove unknown white border of asp:image inside panel <p>I have white border of an asp:image control and i want to remove it but can't find where the problem is</p> <p>here is my html and css:</p> <pre><code>&lt;asp:Panel runat="server" CssClass="nav" ID="nav"&gt; &lt;asp:Image runat="server" ID="Logo" CssClass="logo" /&gt; &lt;asp:LinkButton runat="server" ID="lb1" CssClass="navButtons"&gt;Home&lt;/asp:LinkButton&gt; &lt;asp:LinkButton runat="server" ID="LinkButton1" CssClass="navButtons"&gt;Restorant&lt;/asp:LinkButton&gt; &lt;asp:LinkButton runat="server" ID="LinkButton2" CssClass="navButtons"&gt;Rooms&lt;/asp:LinkButton&gt; &lt;asp:LinkButton runat="server" ID="LinkButton3" CssClass="navButtons"&gt;Spa&lt;/asp:LinkButton&gt; &lt;asp:LinkButton runat="server" ID="LinkButton4" CssClass="navButtons"&gt;Contact&lt;/asp:LinkButton&gt; &lt;asp:LinkButton runat="server" ID="LinkButton5" CssClass="navButtons"&gt;Contact&lt;/asp:LinkButton&gt; &lt;asp:LinkButton runat="server" ID="LinkButton6" CssClass="navButtons"&gt;Contact&lt;/asp:LinkButton&gt; &lt;/asp:Panel&gt; </code></pre> <p>the image with ID="Logo" is white bordered and i need to remove this border</p> <p>CSS of image and Nav panel:</p> <pre><code>.logo { width:100%; height:150px; background-image:url(Background/logo.jpg); float:left; background-repeat:no-repeat; -moz-background-size: 100% 100%; -o-background-size: 100% 100%; -webkit-background-size: 100% 100%; background-size: 100% 100%; position:relative; border:none; } .nav { position:absolute; background-color:black; opacity:0.6; filter: alpha(opacity=60); height:550px; width:250px; z-index:3; max-height:550px; max-width:250px; } </code></pre>