body{
    background-color: gray;
    /* background-image: url(./87860180-yellow-smooth-wave-vector-background-with-white-copy-space-.jpg); */
background-size: cover;
}

.main{
    width: 310px;
    height: 510px;
    margin: 0 auto;
    background-color: #ebebeb;
text-align: center;
    padding: 5px;
margin-top: 50px;
border-radius: 10px;
box-shadow: 0x 0px 10px 1px solid black;
}
.result{
    width: 95.9%;
    position: relative;
    right: 5px;
    bottom: 15px;
    background-color: #46e86f;
height: 90px;
    color: black;
    border: 1px solid #46e86f;

    border-top-left-radius: 10px;
    border-top-right-radius: 10px;
    padding: 10px;
    font-size: 50px;
    margin-top: 10px;
    font-weight: 700;
}
.result:focus , .btn:focus{
    outline: 0;
}
.btnC1 , .btnC2 , .btnC3 , .btnC4{
    margin-left: 20px;
    margin-right: 20px;

    margin-top: 0.1px;
    border-radius: 90px;
    width: 50px;
    height: 50px;
    padding: 7px;
    transition: 0.5s;
    transition: 0.5s;
    font-size: 24px;
    font-weight: 700;
}
.btnC1:focus , .btnC2:focus {
outline: 0;
}
.btnC3:focus , .btnC4:focus {
outline: 0;
}
.halfBtn{
    outline: 0;
}
.btnC1 , .btnC2 , .btnC3 , .btnC4{
    background-color: #46e86f;
    border: 1px solid #46e86f;
}
.btnC2{
    font-size: 20px;

}
.btn{
    background-color: #ebebeb;
    margin: 20px;
    margin-top: 5px;
    border: 1px solid #ebebeb;
    padding: 7px;
    transition: 0.5s;
font-size: 17px;
font-weight: 600;
}
.btn:hover{
    transform: scale(1.1);
    z-index: 2;
color: black;
}
.btnC5 , .btnC6 , .btnC7 , .btnC8{
    background-color: #ebebeb;
    border: 1px solid #ebebeb;
    padding: 30px;
    transition: 0.5s;
    font-size: 17px;
    font-weight: 600;
}
#pi , #back{
    position: relative;
    right: 15px;
}
.btnC5:focus , .btnC6:focus , .btnC7:focus , .btnC8:focus{
    outline: 0;
}
#back{
    position: relative;
    padding: 25px;
    font-size: 20px;
}

.halfBtn{
    background-color: #ebebeb;
    width: 45%;
    margin: 15px;
    margin-top: 5px;

    border: 1px solid #ebebeb;
    font-size: 17px;
    margin-left: 19px;
    font-weight: 600;
/* padding: 7px; */
}
#btn2{
    margin-left: 52px;
    font-weight: 700;
}

#clrBtn{
    font-size: 19px;
    font-weight: bold;
}
#clrBtn2{
    font-size: 17px;
    font-weight: bold;
}
#clrBtn3{
    position: relative;
    right: 5px;
}