CSS animation conflict with background-color

Question

I'm fairly new to animations and cannot figure out why this button won't work as soon as I add either a background-color or background url. The first one works, second doesn't. There is some conflict, I believe, with the background set on the button's after class. I just don't know enough about animations to see why it's conflicting. Any help would be appreciated. Thanks! enter link description here

a.animated-button:link, a.animated-button:visited {
    position: relative;
    display: block;
    margin: 30px auto 0;
    padding: 14px 15px;
    color: #fff;
    font-size:14px;
    font-weight: bold;
    text-align: center;
    text-decoration: none;
    text-transform: uppercase;
    overflow: hidden;
    letter-spacing: .08em;
    border-radius: 0;
    text-shadow: 0 0 1px rgba(0, 0, 0, 0.2), 0 1px 0 rgba(0, 0, 0, 0.2);
    -webkit-transition: all 1s ease;
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
}
a.animated-button:link:after, a.animated-button:visited:after {
    content: "";
    position: absolute;
    height: 0%;
    left: 50%;
    top: 50%;
    width: 150%;
    z-index: -1;
    -webkit-transition: all 0.75s ease 0s;
    -moz-transition: all 0.75s ease 0s;
    -o-transition: all 0.75s ease 0s;
    transition: all 0.75s ease 0s;
}
a.animated-button:link:hover, a.animated-button:visited:hover {
    color: #FFF;
    text-shadow: none;
}
a.animated-button:link:hover:after, a.animated-button:visited:hover:after {
    height: 450%;
}
a.animated-button:link, a.animated-button:visited {
    position: relative;
    display: block;
    margin: 30px auto 0;
    padding: 14px 15px;
    color: #fff;
    font-size:14px;
    border-radius: 0;
    font-weight: bold;
    text-align: center;
    text-decoration: none;
    text-transform: uppercase;
    overflow: hidden;
    letter-spacing: .08em;
    text-shadow: 0 0 1px rgba(0, 0, 0, 0.2), 0 1px 0 rgba(0, 0, 0, 0.2);
    -webkit-transition: all 1s ease;
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
}

/* Victoria Buttons */

a.animated-button.victoria-one {
    border: 2px solid #D24D57;
}
a.animated-button.victoria-one:after {
    background: #D24D57;
    -moz-transform: translateX(-50%) translateY(-50%) rotate(-25deg);
    -ms-transform: translateX(-50%) translateY(-50%) rotate(-25deg);
    -webkit-transform: translateX(-50%) translateY(-50%) rotate(-25deg);
    transform: translateX(-50%) translateY(-50%) rotate(-25deg);
}

<div> <a href="#" class="animated-button victoria-one">Sign up</a> </div>

<div style="background-color:black;"> <a href="#" class="animated-button victoria-one">Sign up</a> </div>

Answer 1

put z-index:1

a.animated-button:link, a.animated-button:visited {
    position: relative;
    z-index:1;
    display: block;
    margin: 30px auto 0;
    padding: 14px 15px;
    color: #fff;
    font-size:14px;
    font-weight: bold;
    text-align: center;
    text-decoration: none;
    text-transform: uppercase;
    overflow: hidden;
    letter-spacing: .08em;
    border-radius: 0;
    text-shadow: 0 0 1px rgba(0, 0, 0, 0.2), 0 1px 0 rgba(0, 0, 0, 0.2);
    -webkit-transition: all 1s ease;
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
}
a.animated-button:link:after, a.animated-button:visited:after {
    content: "";
    position: absolute;
    height: 0%;
    left: 50%;
    top: 50%;
    width: 150%;
    z-index: -1;
    -webkit-transition: all 0.75s ease 0s;
    -moz-transition: all 0.75s ease 0s;
    -o-transition: all 0.75s ease 0s;
    transition: all 0.75s ease 0s;
}
a.animated-button:link:hover, a.animated-button:visited:hover {
    color: #FFF;
    text-shadow: none;
}
a.animated-button:link:hover:after, a.animated-button:visited:hover:after {
    height: 450%;
}
a.animated-button:link, a.animated-button:visited {
    position: relative;
    display: block;
    margin: 30px auto 0;
    padding: 14px 15px;
    color: #fff;
    font-size:14px;
    border-radius: 0;
    font-weight: bold;
    text-align: center;
    text-decoration: none;
    text-transform: uppercase;
    overflow: hidden;
    letter-spacing: .08em;
    text-shadow: 0 0 1px rgba(0, 0, 0, 0.2), 0 1px 0 rgba(0, 0, 0, 0.2);
    -webkit-transition: all 1s ease;
    -moz-transition: all 1s ease;
    -o-transition: all 1s ease;
    transition: all 1s ease;
}

/* Victoria Buttons */

a.animated-button.victoria-one {
    border: 2px solid #D24D57;
}
a.animated-button.victoria-one:after {
    background: #D24D57;
    -moz-transform: translateX(-50%) translateY(-50%) rotate(-25deg);
    -ms-transform: translateX(-50%) translateY(-50%) rotate(-25deg);
    -webkit-transform: translateX(-50%) translateY(-50%) rotate(-25deg);
    transform: translateX(-50%) translateY(-50%) rotate(-25deg);
}

<div> <a href="#" class="animated-button victoria-one">Sign up</a> </div>

<div style="background-color:black;"> <a href="#" class="animated-button victoria-one">Sign up</a> </div>