Edit in JSFiddle

<div class="cover">
  <div class="left_gate"></div>
  <div class="right_gate"></div>

  <h1>Sample Box</h1>   
       <img src="http://www.wpthemegenerator.com/wp-content/uploads/2012/06/Image.jpg">
        <p>
         Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam luctus consectetur dolor a porttitor. Curabitur id sem sed ante fringilla pulvinar et id lectus. Nullam justo ipsum, hendrerit ut commodo nec, pellentesque nec erat. Pellentesque pharetra.
       </p> 
       <br />
       <a href="http://www.designshock.com/"> DesignShock.com </a>
    
</div>

<div class="cover slide_in">
  <div class="left_gate"></div>
  <div class="right_gate"></div>

  <h1>Sample Box</h1>   
       <img src="http://www.wpthemegenerator.com/wp-content/uploads/2012/06/Image.jpg">
        <p>
         Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam luctus consectetur dolor a porttitor. Curabitur id sem sed ante fringilla pulvinar et id lectus. Nullam justo ipsum, hendrerit ut commodo nec, pellentesque nec erat. Pellentesque pharetra.
       </p> 
       <br />
       <a href="http://www.designshock.com/"> DesignShock.com </a>
    
</div>

body {
  font-size: 11px;
  font-family: 'Open Sans', sans-serif;
  color: #4A4A4A ;
  text-align: center;
}

.cover {
  position: relative;
  width: 300px;
  height: 310px;
  margin: 20px auto;
  background-color: #eee;
  z-index: 1;
  padding: 10px;
  
  -webkit-box-shadow: 0 2px 10px rgba(0,0,0,0.3);
  -mox-box-shadow: 0 2px 10px rgba(0,0,0,0.3);
  box-shadow: 0 2px 10px rgba(0,0,0,0.3);
}

.left_gate {
  position: absolute;
  background: #DBDCDE;
  bottom: 0; right: 50%; left: 0; top: 0;
  border:1px solid #F0F0F0;
    
  -webkit-transition: all 0.5s ease-out;
  -moz-transition: all 0.5s ease-out;
  -ms-transition: all 0.5s ease-out;
  -o-transition:all 0.5s ease-out;
  transition: all 0.5s ease-out;
    
    
  
}
.cover:hover .left_gate {
  right: 100%; left: -50%;
}

.right_gate {
  position: absolute;
  background: #DBDCDE;
  bottom: 0;
  left: 50%;
  right: 0;
  top: 0;
  border:1px solid #F0F0F0;
  
  -webkit-transition: all 0.5s ease-out;
  -moz-transition: all 0.5s ease-out;
  -ms-transition: all 0.5s ease-out;
  -o-transition: all 0.5s ease-out;
  transition: all 0.5s ease-out;
}
.cover:hover .right_gate {
  left: 100%; right: -50%;
}

.slide_in {
  overflow: hidden;
}
.slide_in .left_gate {
  background: #DBDCDE;
  border:1px solid #F0F0F0;
}
.slide_in .right_gate {
  background: #DBDCDE;
  border:1px solid #F0F0F0;
}

.cover img {
    width: 100%;
    margin-top: 15px;
}

p{ 
    margin-top: 15px;
    text-align: justify;
}

h1{
    font-size: 20px;
    font-weight: bold;
    margin-top: 5px; 
    text-shadow: 1px 1px 3px rgba(0,0,0,0.3);
}

a{
    text-decoration: none;
    color: #4A4A4A !important;
}

a:hover{
    text-decoration: underline;
    color: #6B6B6B !important ;
}