AutoHide for Editing Mode on Moodle 2.X

autohide.css

/** To hide the icons we are using opacity as display:none makes
the buttons inaccessible. 

FILTER attributes should apply to IE so long as the strict 
doctype is served. Use Filter: none on clear to protect PNG alphas.

Tweak the top opacity values to get "ghost" icons rather than hiding them**/
.block .header .commands a img,
.path-course-view .section .content li .commands img,
.path-course-view .section .content li .commands span.editing_move img,
.path-course-view .section .side img,
.path-course-view .section .section-modchooser a,
.path-course-view .section .content .summary img.edit{
	opacity: 0.01;	
	filter: alpha(opacity=1);
	-o-transition: opacity 0.5s linear 0.3s;
	-moz-transition: opacity 0.5s linear 0.3s;
	-webkit-transition: opacity 0.5s linear 0.3s;
	transition: opacity 0.5s linear 0.3s;
}

.block:hover .header .commands a img,
.block .header .commands a:focus img,
.ie .block .header .commands a:active img,
.path-course-view .section .content li:hover .commands img,
.path-course-view .section .content li .commands a:focus img,
.ie.path-course-view .section .content li .commands a:active img,
.path-course-view .section .content li:hover .commands span.editing_move img,
.path-course-view .section .content li .commands span.editing_move:focus img,
.path-course-view .section .content li .commands span.editing_move img:focus,
.path-course-view .section:hover .side img,
.path-course-view .section .side a:focus img,
.ie.path-course-view .section .side a:active img,
.path-course-view .section:hover .section-modchooser a,
.path-course-view .section:hover .section-modchooser a:focus,
.ie.path-course-view .section:hover .section-modchooser a:active,
.path-course-view .section:hover .content .summary img.edit,
.path-course-view .section .content .summary a:focus img.edit,
.ie.path-course-view .section .content .summary a:active img.edit{
	opacity:1;
	filter: none;
	-o-transition: opacity 0.3s;
	-moz-transition: opacity 0.3s;
	-webkit-transition: opacity 0.3s;
	transition: opacity 0.3s;
}

/** some feedback to tell user we are in editing mode **/
.editing.path-course-view div.content{
	border: 2px #FFD24D dotted;
	box-shadow: #FFD24D 0px 0px 10px;
}

.editing.path-course-view #section-0 div.content{
	border: 1px #FFEFBF dotted;
	box-shadow: #FFEFBF 0px 0px 10px;
}

.path-course-view .section .content .section_add_menus .horizontal > div{
	background-color: #FFD24D;
	padding: .1em 0;
	border: 4px solid #FFD24D;
}

.path-course-view .section .content .section_add_menus .horizontal > div:first-child{
	border-radius: 10px 0 0 10px;
}

.path-course-view .section#section-0  .content .section_add_menus .horizontal > div{
	background-color: #FFEFBF;
	border: 4px solid #FFEFBF;
}

/**if this is a tablet or phone we want to be able to see the icons**/
.tablettheme .block .header .commands a img,
.path-course-view.tablettheme .section .content li .commands a img,
.path-course-view.tablettheme .section .content .summary a img.icon.edit,
.path-course-view.tablettheme  .section .side img,
.mobiletheme .block .header .commands a img,
.path-course-view.mobiletheme .section .content li .commands a img,
.path-course-view.mobiletheme .section .content .summary a img.icon.edit,
.path-course-view.mobiletheme  .section .side img{
	opacity: 0.3;
}

Improved the look of editing mode (hated that red anyway!)

Improved compatibility with Moodle 2.5