#fraction-calc {
    min-width: 1000px;
    /* background-color: bisque; */
    text-align: initial;
    display: flex;
    flex-direction: row;
}

#fc-left {
    width: 65%;
    min-height: 500px;
    display: flex;
    flex-direction: row;
    /* background-color: cadetblue; */
}

#fc-middle {
    width: 120px;
    margin-top: 60px;
    font-size: 3em;
    text-align: center;
}

#fc-right {
    width: 25%;
    min-height: 500px;
    display: flex;
    flex-direction: row;
    /* background-color: aquamarine; */
}

.fc-pads-frac {
    min-width: 300px;
    height: 500px;
    display: flex;
    flex-direction: column;
    align-items: center;
    /* border: solid 1px; */
}

.fc-pads-operator {
    width: 140px;
    height: 300px;
    display: flex;
    align-items: center;
    flex-direction: column;
    /* border: solid 1px; */
}

.frac-viewer {
    width: 300px;
    height: 200px;
    display: flex;
    align-items: center;
    flex-direction: column;
    /* border: solid 1px; */
}

.operator-viewer {
    width: 100%;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    /* border: solid 1px; */
}

.frac-viewer-operator {
    font-size: 80px;
}

.frac-viewer-item {
    min-width: 300px;
    min-height: 20px;
    font-size: 3em;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;

}

.frac-viewer-item.num-view {
    min-width: 100px;
    height: 75px;
}


.frac-viewer-item hr {
    width: 99%;
    border-top: 6px solid;
}

#calc input {
    width: 300px;
}

.fc {
    width: 300px;
    user-select: none;
    margin: 20px 20px 0 20px;
}

.fc hr {
    border-top: 6px solid;
}

.fc-pad {
    width: 300px;
    margin: 20px 0 20px 0;
}

.fc-row {
    width: 100%;
    display: flex;
    justify-content: center;
}

.fc-button {
    border: 3px outset #b5b5b5;
    width: 60px;
    height: 45px;
    margin: 1px;
    font-size: 2em;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #d6d6d6;
    color: rgb(32, 32, 32);
    cursor: pointer;
    border-radius: 0.5rem;
}

.fc-button.numkey {
    width: 40px;
    font-size: 2em;
}

.fc-button.funkey {
    width: 80px;
    margin: 1px 1px 1px 10px;
    font-size: 1.5em;
}

.fc-operators {
    width: 100px;
    margin-top: 40px;
    user-select: none;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    /* background-color: #c78947; */
}

.fc-operator {
    border: 3px outset #b5b5b5;
    width: 80px;
    height: 45px;
    margin: 1px;
    font-size: 2em;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #d6d6d6;
    color: rgb(32, 32, 32);
}

.fc-operator.common{
    font-size: 1em;
}

.answer-viewer-box{
    width: 49%;
    display: flex;
    flex-direction: column;
}
.frac-viewer.answer-viewer {
    width: 100%;
}

.frac-viewer-item.answer-viewer-item {
    min-width: 100px;
    height: 75px;
}

.answer-title{
    text-align: center;
}

/* ref: https://q-az.net/buruburu-hurueru-css/ */
.error-shiver {
    animation: hurueru .1s 5;
}

@keyframes hurueru {
    0% {
        transform: translate(0px, 0px) rotateZ(0deg)
    }

    25% {
        transform: translate(2px, 2px) rotateZ(1deg)
    }

    50% {
        transform: translate(0px, 2px) rotateZ(0deg)
    }

    75% {
        transform: translate(2px, 0px) rotateZ(-1deg)
    }

    100% {
        transform: translate(0px, 0px) rotateZ(0deg)
    }
}