.smallfonts{
    font-size: 0.8em;
}
.formula{
    margin: 30px 0;
    padding: 30px 0 15px;
    border-top: 1px solid #ccc;
}
h2{
    margin: 0 0 30px;
    font-weight: 400;
    font-size: 18px;
    color: #47a2da;
}
.formline{
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}
.formline,
input{
    font-size: 13px;
    font-weight: bold;
}
.formitem{
    position: relative;
    padding-bottom: 30px;
    top: 18px;
    margin-bottom: 5px;
}
label{
    position: absolute;
    bottom: 10px;
    width: 100%;
    text-align: center;
    transition: all 300ms ease-out;
}
input.red,
input.red:focus{
    color: #cc3333;
}
sup{
    position: relative;
    top: -10px;
}
.symbols{
    white-space: nowrap;
    padding: 15px 0;
    display: inline-block;
}
input{
    border: none;
    padding: 3px;
    margin: 0 5px;
    transition: all 300ms ease-out;
    font-size: 15px;
    width: 52px;
    text-align: center;
    outline: none;
    font-family: 'Courier New', monospace;
}
input:focus{
    outline: none;
}
.imgwrap{
    position: relative;
    margin-bottom: 20px;
}
.imgwrap > img{
    display: block;
    margin: 0 auto;
}
img[src*="-2.png"]{
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    display: block;
    opacity: 0;
    transition: all 1s ease-out;
    margin: 0;
}
.imgtwo img[src*="-2.png"]{
    opacity: 1;
}

.area-item{
    border: 3px solid #d2d433;
}
.radi-item{
    border: 3px solid #d42a2d;
}
.peri-item{
    border: 3px solid #309f39;
}
.sida-item{
    border: 3px solid #1fbdcc;
}
.sidb-item{
    border: 3px solid #2177b0;
}
.sidc-item{
    border: 3px solid #7f7f7f;
}
.sidd-item{
    border: 3px solid #8b564c;
}
.heig-item{
    border: 3px solid #9267b9;
}
.volu-item{
    border: 3px solid #e178bf;
}
.surf-item{
    border: 3px solid #fd7f2a;
}