Adverts are bad enough...

But when they overlap the main menu making it impossible to even USE?!? GAH.

Needless to say, I've added:
#header_middle { display:none !important; }

To my already massive user.css to force this train wreck of a theme into being usable.

 

Also if you think your css file is getting over cluttered, you can also use different files and import them the main css file

 

By about two star systems. Have the suspicion that @shemseddine has no clue what "user.css" is...

user.css refers to client-side CSS you add in THE BROWSER to try and make poorly written inaccessible websites usable. Basically it's a way to add your own style in the browser as a visitor to a site to override poor choices made by the site's owner.

I do this because the current theme as it sits is an accessibility train wreck with it's endless pointless code bloat and "WCAG, what's that?" design. It's something Opera USED to have built in by default -- which is why I'm STILL on Opera 12.17 since everything else is pathetic crippleware in terms of the UI by comparison... particularly the annoyingly useless ChrOpera.

For those interested in what I'm currently running as a user.js to make this site USABLE:

* {
	font-size:100% !important;
	line-height:140% !important;
	font-family:arial,helvetica,sans-serif !important;
}

body {
	font-size:85% !important;
}

.messageUserInfo {
	width:12em !important;
}

.messageInfo {
	width:auto !important;
	margin-left:13em !important;
}

.navTabs {
	font-size:16px !important;
}

.navTabs a {
	line-height:25px !important;
}

.blockLinksList a {
	line-height:20px !important;
}

#header_middle,
.socialBar {
	display:none !important;
}

.newIndicator {
	color:#EFC !important;
}

.privateControls span a {
	line-height:2em !important;
}

.button,
.privateControls a.item,
.publicControls a {
	height:auto !important;
	padding:0.2em 0.5em !important;
}

.publicControls a {
	display:inline-block;
}

.scrollable {
	height:2em !important;
}

.pageNavHeader{
padding-right:0.4em !important;
}

.button,
.publicControls a,
.privateControls a.item,
.PageNav a {
	color:#000;
	background:#EFD !important;
	border:1px solid;
	border-color:#749B85 #749B85 #618872;
	-webkit-border-radius:7px;
	-moz-border-radius:7px;
	border-radius:7px;
	-webkit-box-shadow:
		0px 1px 4px 0px #C8C8D2,
		inset 0 4px 8px #FFF,
		inset 0 -4px 8px #BDB;
	-moz-box-shadow:
		0px 1px 4px 0px #C8C8D2,
		inset 0 4px 8px #FFF,
		inset 0 -4px 8px #BDB;
	box-shadow:
		0px 1px 4px 0px #C8C8D2,
		inset 0 4px 8px #FFF,
		inset 0 -4px 8px #BDB;
}

.button:active,
.button:focus,
.button:hover,
.publicControls a:active,
.publicControls a:focus,
.publicControls a:hover,
.pageNav a:active,
.pageNav a:focus,
.pageNav a:hover {
	background:#CEC !important;
}

#AlertsMenu_Counter .arrow,
#header_data,
#header_middle,
.underPost {
	display:none;
}

#AlertsMenu_Counter {
	position:relative !important;
	top:0 !important;
	padding:0.1em 0.4em;
}

.formPopup {
	width:16em !important;
}

#QuickSearchQuery {
	width:15em !important;
}

#QuickSearch * {
	line-height:1.4em !important;
}

#QuickSearch input.button.primary {
	width:auto !important;
	margin-right:0.4em;
	padding:0.2em 0.5em !important;
}

#QuickSearch a.moreOptions {
	overflow:hidden;
	display:block;
	margin:0;
	padding:0.2em 0 !important;
	height:auto !important;
}

#commonSearches {
	margin-left:0.4em;
	padding:0.2em 0.5em !important;
	height:auto !important;
}

.pageNavLinkGroup a {
	width:auto !important;
	padding:0.1em 0.2em !important;
}

#messageList li:nth-child(even) {
	background: #E0FFD0; /* Old browsers */
	background: -o-linear-gradient(left, #fcfcff 0%,#E0FFD0 50%,#fcfcff 100%); /* Opera 11.10+ */
	background: linear-gradient(to right, #fcfcff 0%,#E0FFD0 50%,#fcfcff 100%); /* W3C */
}

#messageList .messageInfo {
	background:transparent;
}

.code * { font-family:consolas,monospace !important;}

.node .nodeLastPost { height:auto !important; }

Code (markup):

As to pulling a screencap, I'm turning off the killing of that add to see if it happens again. There was one advert with a box-shadow on it that repeatedly showed up over the menu bar.

Though to be frank, that fat bloated garbage menu really needs a nice big axe swung at it to simplify things down a bit. Talk about waste of bandwidth and link-overload.

 

Can you tried a different web browser?

Maybe that would fix the bug you are experiencing.

 

Dunno I does, canz I havez intarnetz?

Using other browsers means I can't turn off all the annoying crap or make the website usable -- but I did test FF in addition to "real" Opera before posting -- and when the offending ad appears (seems to be one with a box-shadow that's rotated slightly) it does it there too.