How to add shadow & box to the article

Dear guys,

I must say that t3 framework is awesome. Thank you for developing such a wonderful framework for Joomla. I have a question for you guys. I want to add a shadow effect to my articles, but to no avail.

The code that I used is

.article {
background: #fff;
box-shadow: 0 0 10px rgba(0,0,0,0.3);
margin: 26px auto 0;
max-width: 550px;
min-height: 300px;
padding: 24px;
position: relative;
width: 80%;
}
.article:before, .article:after {
content: "";
height: 98%;
position: absolute;
width: 100%;
z-index: -1;
}
.article:before {
background: #fafafa;
box-shadow: 0 0 8px rgba(0,0,0,0.2);
left: -5px;
top: 4px;
transform: rotate(-2.5deg);
}
.article:after {
background: #f6f6f6;
box-shadow: 0 0 3px rgba(0,0,0,0.2);
right: -3px;
top: 1px;
transform: rotate(1.4deg);
}

However nothing happens, only when I add the suffix like -content, -header after the .article, then I can modify some part of the article. I wonder if there is any way for me to modify the article display.

Thank you very much guys.

Jinshang