Background not coming in ie8 - html

Question

When I put the navigation background image is not coming in ie8 ie7. all other browsers are ok. I Have added the code below . Can anyone please help me to fix this is issue?/
<nav class="navigation">
<ul>
<li><a href="http://www.ticketstosrilanka.co.uk/" >Home</a></li>
<li>Flights</li>
<li>Travel Guide</li>
<li>Tours & Holidays</li>
<li>About us</li>
<li>Contact Us</li>
</ul>
</nav>
.navigation {
margin: 0px 0;
font: bold 12px/18px "Helvetica Neue", Helvetica, Arial, sans-serif;
text-transform: uppercase;
color: #444;
width:100%;
background: url("../images/menubg.png")repeat-x scroll left top transparent;
-webkit-box-shadow: 0 1px rgba(255,255,255,1) inset;
}
.navigation:after {
clear: both;
content: ".";
display: block;
height: 0;
visibility: hidden;
}
.navigation ul {
float: left;
border-radius: 0px;
box-shadow: 0 2px 2px rgba(0, 0, 0, 0.07);
-webkit-box-shadow: 0 2px 2px rgba(0, 0, 0, 0.07);
overflow: hidden;
}
.navigation li {
float: left;
border-style: solid;
border-width: 1px;
border-color: #BABABA #BABABA #BABABA #FFF;
box-shadow: 0 1px rgba(255,255,255,1) inset;
-webkit-box-shadow: 0 1px rgba(255,255,255,1) inset;
background: #F7F7F7; /* Old browsers */
background: -moz-linear-gradient(top, #F7F7F7 0%, #EDEDED 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#F7F7F7), color-stop(100%,#EDEDED)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #F7F7F7 0%,#EDEDED 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #F7F7F7 0%,#EDEDED 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #F7F7F7 0%,#EDEDED 100%); /* IE10+ */
background: linear-gradient(top, #F7F7F7 0%,#EDEDED 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#F7F7F7', endColorstr='#EDEDED',GradientType=0 ); /* IE6-9 */
}
.navigation li:hover, navigation li.current {
box-shadow: 0 1px rgba(255,255,255,0.2) inset;
-webkit-box-shadow: 0 1px rgba(255,255,255,0.2) inset;
border-color: #262626 !important;
background: #4D4D4D; /* Old browsers */
background: -moz-linear-gradient(top, #4D4D4D 0%, #262626 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#4D4D4D), color-stop(100%,#262626)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #4D4D4D 0%,#262626 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #4D4D4D 0%,#262626 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #4D4D4D 0%,#262626 100%); /* IE10+ */
background: linear-gradient(top, #4D4D4D 0%,#262626 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#4D4D4D', endColorstr='#262626',GradientType=0 ); /* IE6-9 */
}
.navigation a {
display: block;
padding: 10px 15px;
color: #444;
text-decoration: none;
text-shadow: 0 1px #FFF;
}
.navigation a.active{
box-shadow: 0 1px rgba(255,255,255,0.2) inset;
-webkit-box-shadow: 0 1px rgba(255,255,255,0.2) inset;
border-color: #262626 !important;
background: #4D4D4D; /* Old browsers */
background: -moz-linear-gradient(top, #4D4D4D 0%, #262626 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#4D4D4D), color-stop(100%,#262626)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #4D4D4D 0%,#262626 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #4D4D4D 0%,#262626 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #4D4D4D 0%,#262626 100%); /* IE10+ */
background: linear-gradient(top, #4D4D4D 0%,#262626 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#4D4D4D', endColorstr='#262626',GradientType=0 ); /* IE6-9 */
color:#fff;
}
.navigation a:hover, #navigation li.current a {
color: #FFF;
text-shadow: 0 1px #000;
}
.navigation li:first-child {
border-left-color: #BABABA;
border-radius: 0px 0 0 0px;
}
.navigation li:last-child {
border-radius: 0 0px 0px 0;
}

Answer 1

Just add float: left; to your .navigation this may solve your problem, if not , try by adding
* html .navigation{height: 1%;}

Answer 2

Now add this
.navigation {
background: url("../images/menubg.png") repeat-x left top; // add this line
background: url("../images/menubg.png")repeat-x scroll left top transparent; // remove this line
}
Live demo