Navigation and Ribbons not displaying right in IE

[hydrix]

I'm encountering 2 problems in ie atm. The first is my navigation menu, The links are stacking on top of each other instead of going across the bar. Here is my code for the nav menu.

HTML

<div  class="main-navigation" role="navigation" style="margin-top: 5px;">
	<div class="nav-menu"><ul><li class="page_item page-item-8"><a href="http://tshirthideout.com/design-your-own/">design your own</a></li><li class="page_item page-item-10"><a href="http://tshirthideout.com/fan-photos/">fan photos</a></li><li class="page_item page-item-12"><a href="https://tshirthideout.com/win-a-free-t-shirt/">Win a free T-shirt</a></li></ul></div>
</div><!-- #site-navigation -->

CSS

.main-navigation li {
    margin: 0px 20px 0px 0px;
    position: relative;
    text-align: center;
    padding: 7px 0px;
}

	.main-navigation li ul {
		display: none;
		margin: 0;
		padding: 0;
		position: absolute;
		top: 100%;
		z-index: 1;
	}
	.main-navigation li ul ul {
		top: 0;
		left: 100%;
	}
	.main-navigation ul li:hover > ul {
		border-left: 0;
		display: block;
	}
	.main-navigation li ul li a {
		background: #efefef;
		border-bottom: 1px solid #ededed;
		display: block;
		font-size: 11px;
		font-size: 0.785714286rem;
		line-height: 2.181818182;
		padding: 8px 10px;
		padding: 0.571428571rem 0.714285714rem;
		width: 180px;
		width: 12.85714286rem;
		white-space: normal;
	}
	.main-navigation li ul li a:hover {
		background: #e3e3e3;
		color: #444;
	}
	.main-navigation .current-menu-item > a,
	.main-navigation .current-menu-ancestor > a,
	.main-navigation .current_page_item > a,
	.main-navigation .current_page_ancestor > a {
		color: #cb0000;
		font-weight: bold;
	}

The second problem is with my 2 ribbons i have for titles in the side bar.
The right bottom flap that give it the wrap around look is not showing up.

HTML

<div class="ribbon"><strong>SPECIAL OFFERS</strong></div>

CSS

.ribbon {
padding-bottom: 7px;
padding-top: 8px;
    padding-left: 3px;
    color: #fff;
        text-shadow: 1px 1px 0px #c1c1c1;
        font-size: 15px;font-family:'Century Gothic',futura,'URW Gothic L',Verdana,sans-serif;
        letter-spacing: 5px;
position:relative;
    width:267px;
   
    right:0px;
    top:19px;
    background-color:#212121;
-moz-border-radius:2px 0px 0px 2px;  /*radius of 2px*/
-khtml-border-radius:2px 0px 0px 2px;
-webkit-border-radius:2px 0px 0px 2px;
-webkit-box-shadow: -2px 2px 4px rgba(50, 50, 50, 0.35);
-moz-box-shadow:    -2px 2px 4px rgba(50, 50, 50, 0.35);
box-shadow:         -2px 2px 4px rgba(50, 50, 50, 0.35);
}
.ribbon:after {
    content:'';
    width:0;
    height:0;
    
    border-color: #000 transparent transparent #000;
    border-style:solid;
    border-width:5px 5px;
    
    position:absolute;
    right:0;
    bottom:-10px;
}

If anyone can help that would be great, I have been trying to figure this out for hours.