a:focus,
a:hover {
    text-decoration: none
}

.btn,
a {
    -webkit-transition: all .5s;
    -moz-transition: all .5s;
    transition: all .5s
}

.container {
    width: 94%
}

:focus {
    box-shadow: 0 0 0 transparent
}

.calculator {
    background: #68bdf3;
}

.displayBox {
    background: #292929;
    overflow: hidden
}

.displayText {
    color: #FFF;
    font-size: 60px;
    font-weight: 100;
    overflow: hidden;
    text-align: right;
    padding-right: 20px;
    float: right;
}

.btn-calc,
.btn-calc:focus,
.btn-operation,
.calu-w3ls,
.calu-w3ls:focus {
    font-size: 25px;
    font-weight: 100;
    box-shadow: 0 0 0 transparent;
    outline: 0;
    border: none;
}

.operationSide {
    background: #FFF;
}

.btn-calc,
.btn-calc:focus {
    background: rgba(255, 255, 255, 0.17);
    color: #fff;
    width: 62px;
    height: 62px;
    border-radius: 100px;
    border: none;
    margin: 6px 10px;
    box-shadow: 2px 3px 5px 1px rgba(0, 0, 0, 0.16);
}

.btn-calc:hover {
    background: #FFF;
    color: #455A64;
    -webkit-transition: 0.5s all;
    -o-transition: 0.5s all;
    -moz-transition: 0.5s all;
    -ms-transition: 0.5s all;
    transition: 0.5s all;
}

.btn-operation {
    background: 0 0;
    color: #999;
    width: 100%;
    height: 80px;
    border-radius: 0
}

.btn-operation:focus,
.btn-operation:hover {
    background: #E8E8E8;
    color: #444;
    -webkit-transition: 0.5s all;
    -o-transition: 0.5s all;
    -moz-transition: 0.5s all;
    -ms-transition: 0.5s all;
    transition: 0.5s all;
}

.btn-operation:focus {
    outline: 0
}

.equals,
.equals:focus,
.equals:hover {
    background: #292929;
    color: #FFF;
    -webkit-transition: 0.5s all;
    -o-transition: 0.5s all;
    -moz-transition: 0.5s all;
    -ms-transition: 0.5s all;
    transition: 0.5s all;
}

.calu-w3ls,
.calu-w3ls:focus {
    background: #292929 !important;
    color: #FFF;
    width: 62px;
    height: 62px;
    border-radius: 100px;
    border: transparent;
    box-shadow: 2px 3px 5px 1px rgba(0, 0, 0, 0.16);
    margin: 6px 10px;
}

.calu-w3ls:hover {
    background: #455A64;
    color: #FFF;
    -webkit-transition: 0.5s all;
    -o-transition: 0.5s all;
    -moz-transition: 0.5s all;
    -ms-transition: 0.5s all;
    transition: 0.5s all;
}

.equals,
.equals:focus {
    width: 100%;
    height: 96px
}

.btn-question,
.btn-question:focus {
    z-index: 100;
    position: absolute;
    top: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
    border-radius: 40px;
    background: 0 0;
    border: 2px solid #FFF;
    padding-top: 6px;
    color: #FFF;
    font-family: sans-serif;
    font-size: 18px;
    outline: 0
}

.btn-question:hover {
    background: rgba(255, 255, 255, .2);
    color: #FFF;
    -webkit-transition: 0.5s all;
    -o-transition: 0.5s all;
    -moz-transition: 0.5s all;
    -ms-transition: 0.5s all;
    transition: 0.5s all;
}

.hvr-fade:before,
.hvr-radial-out:before {
    background: #FFF !important;
    transition-duration: .5s
}

:focus {
    outline: 0 !important
}

::-moz-focus-inner {
    border: 0 !important
}

/* responsive */

@media(max-width: 667px) {
    .btn-calc,
    .btn-calc:focus,
    .btn-operation,
    .calu-w3ls,
    .calu-w3ls:focus {
        font-size: 22px;
    }
    .btn-calc,
    .btn-calc:focus,
    .calu-w3ls,
    .calu-w3ls:focus {
        width: 55px;
        height: 55px;
    }
    .btn-operation {
        height: 70px;
    }
    .equals,
    .equals:focus {
        height: 87px;
    }
}

@media(max-width: 600px) {
    .displayText {
        font-size: 50px !important;
    }
}

@media(max-width: 414px) {
    .btn-calc,
    .btn-calc:focus,
    .calu-w3ls,
    .calu-w3ls:focus {
        width: 50px;
        height: 50px;
        margin: 6px 7px;
    }
    .btn-operation {
        height: 65px;
    }
    .equals,
    .equals:focus {
        height: 82px;
    }
}

@media(max-width: 320px) {
    .btn-calc,
    .btn-calc:focus,
    .calu-w3ls,
    .calu-w3ls:focus {
        width: 42px;
        height: 42px;
        margin: 6px 6px;
    }
    .btn-calc,
    .btn-calc:focus,
    .btn-operation,
    .calu-w3ls,
    .calu-w3ls:focus {
        font-size: 18px;
    }
    .btn-operation {
        height: 60px;
    }
    .equals,
    .equals:focus {
        height: 62px;
    }
}

/* //responsive */