p.error
{
    border:none;
    color:green;
    display:block;
    font-family: Calibri;
    font-size:12px;
    font-weight:700;
    line-height:150%;
    padding:0 0 1px;
}

span.statusFailed
{
    color:red;
    font-family: Calibri;
    font-size:14px;
    font-weight:700;
    line-height:150%;

}

* {
padding:0px;
margin:0px;
}
body
{
background:#ffffff;
font-family:"Lucida Grande", Tahoma, Arial, Verdana, sans-serif;
font-size:small;
margin:8px 0 16px;
margin: 0;
padding:0;

}

#nav
{
background-color:#ccc;
height:19px;
width:1024px;
font-family:Calibri;
}

#nav ul {
list-style-type: none;
}

#nav li {
    float: left; position: relative;
}

#nav li a {
padding-right: 20px;
padding-left: 15px;
display: block;
line-height: 20px;
text-decoration: none;
font-family: Calibri;
font-size: 15px;
color: #371C1C;
}

#nav a:hover,
#nav a:focus {
    text-decoration:none;
}

h2.form_desicription
{
    clear:left;
    font-family: Calibri;
  font-size: 18px;
  color: #371C1C;

}


input.text
{
    background:#fff url(../../../images/shadow.gif) repeat-x top;
    border-bottom:1px solid #ddd;
    border-left:1px solid #c3c3c3;
    border-right:1px solid #c3c3c3;
    border-top:1px solid #7c7c7c;
    color:#333;
    font-family: Calibri;
    font-size:15px;
    font-weight:700;
    line-height:normal;
    padding:2px 0;
}

input.radio
{
    color:#333;
    font-family: Calibri;
    font-size:15px;
    font-weight:700;
    line-height:normal;
    padding:2px 0;
}
input.checkbox
{
    color:#333;
    font-family: Calibri;
    font-size:15px;
    font-weight:700;
    line-height:normal;
    padding:2px 0;
}

label.description
{
    border:none;
    color:#222;
    display:block;
    font-family: Calibri;
    font-size:15px;
    font-weight:700;
    line-height:150%;
    padding:0 0 1px;
}

label.list
{
    border:none;
    color:#222;
    font-family: Calibri;
    font-size:15px;
    font-weight:700;
    line-height:150%;
    padding:0 0 1px;
}

input.file
{
    color:#333;
    font-family: Calibri;
    font-size:13px;
    font-weight:700;
    line-height:150%;
    margin:0;
    padding:2px 0;
}

select.select
{
    color:#333;
    font-family: Calibri;
    font-size:15px;
    font-weight:700;
    line-height:normal;
    padding:2px 0;
}

textarea.textarea
{
    color:#333;
    font-family: Calibri;
    font-size:15px;
    font-weight:700;
    margin:1px 0;
    padding:1px 0 0;
    border-bottom:1px solid #ddd;
    border-left:1px solid #c3c3c3;
    border-right:1px solid #c3c3c3;
    border-top:1px solid #7c7c7c;
}

input.button_text
{
    overflow:visible;
    padding:0 7px;
    width:auto;
}

.buttons input
{
    font-family: Calibri;
    font-size:13px;
    font-weight:700;
    margin-right:5px;
}

span.required
{
    border:none;
    color:red;
    display:block;
    font-family: Calibri;
    font-size:15px;
    font-weight:700;
    line-height:150%;
    padding:0 0 1px;
}

#gridHeader
{
background-color:#ccc;
font-size:12px;
font-color:#ffffff;
font-family:Calibri;
}

#gridRow
{
background-color:#EFEEEE;
font-size:12px;
font-family:Calibri;
}
#gridRow10
{
background-color:#EFEEEE;
font-size:8px;
font-family:Calibri;
}

p.error
{
    border:none;
    color:green;
    display:block;
    font-family: Calibri;
    font-size:12px;
    font-weight:700;
    line-height:150%;
    padding:0 0 1px;
}
span.clearSearch
{
    font-family: Calibri;
    font-size:12px;
    font-weight:700;
    line-height:150%;
}
span.statusOk
{
    color: blue;
    font-family: Calibri;
    font-size:14px;
    font-weight:700;
    line-height:150%;

}
span.statusFailed
{
    color:red;
    font-family: Calibri;
    font-size:14px;
    font-weight:700;
    line-height:150%;

}

.show
{
    display: block;
    visibility: visible;
}
.hide
{  display: none;
    visibility: hidden;
}

<p class="statusFailed someOtherClass">Words</p>

p{

    color:red;
    /* etc... */

}

p.statusFailed {
    color: red !important;
    /**
     * the rest of your css
     */
}