Code Snippet

Page Curl Shadows

.page-curl {
position: relative;
background: #ffffff;
background: -moz-linear-gradient(top, #ffffff 0%, #e5e5e5 100%);
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#ffffff), color-stop(100%,#e5e5e5));
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#ffffff', endColorstr='#e5e5e5',GradientType=0 );
-webkit-box-shadow: 0px 0px 3px rgba(0, 0, 0, 0.3);
-moz-box-shadow: 0px 0px 3px rgba(0, 0, 0, 0.3); }

.page-curl:after {
z-index: -1;
position: absolute;
background: transparent;
width: 70%;
height: 55%;
content: '';
right: 10px;
bottom: 10px;
-webkit-transform: skew(15deg) rotate(5deg);
-webkit-box-shadow: 8px 12px 10px rgba(0, 0, 0, 0.3);
-moz-transform: skew(15deg) rotate(5deg);
-moz-box-shadow: 8px 12px 10px rgba(0, 0, 0, 0.3); }

.page-curl:before {
z-index: -2;
position: absolute;
background: transparent;
width: 70%;
height: 55%;
content: '';
left: 10px;
bottom: 10px;
-webkit-transform: skew(-15deg) rotate(-5deg);
-webkit-box-shadow: -8px 12px 10px rgba(0, 0, 0, 0.3);
-moz-transform: skew(-15deg) rotate(-5deg);
-moz-box-shadow: -8px 12px 10px rgba(0, 0, 0, 0.3); }

Be careful that these boxes aren't sitting within another element that has a background, otherwise the negative z-index values (required for this to work) will force the shadows underneath that and not show up.

Reference URL