.content {
    width:480px;
    margin:20px auto 0;
}

.calculator {
    width:480px;
    height:auto;
    padding:10px 0;
    margin: auto;
    background:#232323;
    border:#000 1px solid;
    border-radius:7px;
    -webkit-border-radius:7px;
    -moz-border-radius:7px;
    box-shadow:rgba(0,0,0,0.4) 0px 2px 5px, inset rgba(255,255,255,0.9) 0px 1px 1px -1px;
    -webkit-box-shadow:rgba(0,0,0,0.4) 0px 2px 5px, inset rgba(255,255,255,0.9) 0px 1px 1px -1px;
    -moz-box-shadow:rgba(0,0,0,0.4) 0px 2px 5px, inset rgba(255,255,255,0.9) 0px 1px 1px -1px;
    background-image:-moz-linear-gradient(top, #333333, #1f1f1f);
    background-image:-webkit-linear-gradient(top, #333333, #1f1f1f);
    background-image:linear-gradient(top, #333333, #1f1f1f);
    overflow: hidden;
    text-align: center;
    margin-bottom: 20px;
}

.screen {
    width:424px;
    height:93px;
    margin: 12px auto 30px;
    padding:15px 20px;
    color:#c0c0c0;
    text-align: right;
    font-size: 3em;
    letter-spacing: 3px;
    overflow:hidden;
    border:#000 1px solid;
    border-radius:7px;
    -webkit-border-radius:7px;
    -moz-border-radius:7px;
    box-shadow:inset rgba(0,0,0,1) 0px 1px 4px, inset rgba(225,225,225,0.3) 0px -2px 4px -2px;
    -webkit-box-shadow:inset rgba(0,0,0,1) 0px 1px 4px, inset rgba(225,225,225,0.3) 0px -2px 4px -2px;
    -moz-box-shadow:inset rgba(0,0,0,1) 0px 1px 4px, inset rgba(225,225,225,0.3) 0px -2px 4px -2px;
    background-image: -moz-linear-gradient(top, #3e3e3e 0%, #303030 100%);
    background-image: -webkit-linear-gradient(top, #3e3e3e 0%, #303030 100%);
    background-image: linear-gradient(top, #3e3e3e 0%, #303030 100%);
    -moz-box-sizing:border-box;
    -webkit-box-sizing:border-box;
    box-sizing:border-box;
}

.buttons {
    padding:0;
    width:423px;
    margin:auto;
    overflow: hidden;
    list-style: none;
}
.buttons li {
    display:inline;
    float:left;
    padding:0px;
    margin-right:13px;
    margin-bottom:10px;
}
.buttons li:nth-child(4n) {
    margin-right:0;
}

.buttons a{
    display:block;
    width:95px;
    height:68px;
    padding:18px 0 12px;
    color:#c0c0c0 !important;
    font-family: "Myriad Pro", Arial, sans-serif;
    font-size:1.6em;
    font-weight: 500;
    letter-spacing: -2px;
    background-color:#2f2f2f;
    border: #000 1px solid;
    border-radius:5px;
    -webkit-border-radius:5px;
    -moz-border-radius:5px;
    text-align: center;
    text-decoration: none;
    text-shadow:#000 0px -1px 0px;
    box-shadow: inset rgba(255,255,255,0.1) 0px 1px 0px, inset rgba(0,0,0,0.2) 0px -2px 2px;
    -webkit-box-shadow: inset rgba(255,255,255,0.1) 0px 1px 0px, inset rgba(0,0,0,0.2) 0px -2px 2px;
    -moz-box-shadow: inset rgba(255,255,255,0.1) 0px 1px 0px, inset rgba(0,0,0,0.2) 0px -2px 2px;
    background-image:-moz-linear-gradient(top, #363636 0%, #313234 40%, #2f2f2f 100%);
    background-image:-webkit-linear-gradient(top, #363636 0%, #313234 40%, #2f2f2f 100%);
    background-image:linear-gradient(top, #363636 0%, #313234 40%, #2f2f2f 100%);
    -moz-box-sizing:border-box;
    -webkit-box-sizing:border-box;
    box-sizing:border-box;
    cursor: pointer;
}
.buttons a:active{
    box-shadow: inset rgba(0,0,0,0.5) 0px 2px 8px;
    background-image:-moz-linear-gradient(top, #2f2f2f 0%, #363636 100%);
    background-image:-webkit-linear-gradient(top, #2f2f2f 0%, #363636 100%);
    background-image:linear-gradient(top, #2f2f2f 0%, #363636 100%);
}
.tall{height:151px !important;}
.wide{width:205px !important;}
.shift{margin-top:-78px;}

.ctrls{
    list-style: none;
    margin:5px 0 0 20px;
    padding:0;
    position: absolute;
}
.ctrls li{
    float:left;
    display:inline;
}
.ctrls li a{
    display: block;
    width:18px;
    height:18px;
    margin-right:10px;
    border-radius:100%;
    box-shadow:rgba(255,255,255,0.3) 0px 0px 1px, inset rgba(0,0,0,1) 0px 1px 2px 1px;
    background-image: -moz-radial-gradient( 9px -4px, #FFF 0px, #fff 2px, rgba(255,255,255,0) 4px), -moz-linear-gradient(bottom, rgba(255,255,255,0.5) 0%, rgba(255,255,255,0) 100%);
    background-image: -webkit-radial-gradient( 9px -4px, #FFF 0px, #fff 2px, rgba(255,255,255,0) 4px), -webkit-linear-gradient(bottom, rgba(255,255,255,0.5) 0%, rgba(255,255,255,0) 100%);
    background-image: radial-gradient( 9px -4px, #FFF 0px, #fff 2px, rgba(255,255,255,0) 4px), linear-gradient(bottom, rgba(255,255,255,0.5) 0%, rgba(255,255,255,0) 100%);
}
h3{
    color: red;
} header{
      background: linear-gradient(141deg, #0fb8ad 0%, #1fc8db 51%, #2cb5e8 75%);
  }
header h1{
    font-family: 'Tangerine', serif;
    padding: 3%;
    text-align: center;
    color: whitesmoke;
}
header h2{
    font-family: 'Tangerine', serif;
    text-align: center;
    color: whitesmoke;
}
section{
    height: 80%;
    display: -webkit-flex;
    display: flex;
    flex-flow: row;

}
article{
    background: #8af6ef;
    flex:20%;
    order: 1;
}