<asp:Button ID="btnSearch" runat="server" OnClick="btnSearch_Click"  Style="width: 480px;" CssClass="button" Text="Search" />
      <style type="text/css">
.button
{
    background: white;
    border: solid 1px grey;
    font-family: Arial, sans-serif;
    font-size: 12px;
    font-weight: bold;
    color: #001563;    
    height: 25px;  

}

.button:hover
{
    background: white;
    border: solid 1px grey;
    font-family: Arial, sans-serif;
    font-size: 12px;
    font-weight: bold;
    color: Red;   
    height: 25px;

}</style>