main.css

html{
    height: 100%;
}
body{
    background-image: linear-gradient(to bottom right, #dd00cb, #ff8f0e);
}
#calculator {
    font-family:'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: azure;
    background-color: #7a06ff;
    background-image: linear-gradient(to bottom right, #861cff, #6606ff );
    width: 350px;
    height: 570px;
    position: absolute;
    left: calc(50% - 175px);
    top:  calc(50% - 285px);
    border-radius: 6px ;
    box-shadow: 0px 0px 33px -1px rgba(0,0,0,0.75);
    user-select: none;
}

h1{
    font-weight: 400;
}

#first{
    width: 100%;
    height: 30%;
    box-shadow: inset 0 -9px 13px -11px rgba(0,0,0,0.75);
}

#buttons_first{    
    display: grid;
    background-image: linear-gradient(to bottom right, rgb(132, 24, 255), rgb(177, 109, 255));
    width: 100%; 
    height: 70%;
    grid-template-columns: 1fr 1fr 1fr 1fr;
    grid-template-rows: 79.8px 79.8px 79.8px 79.8px 79.8px; 
    grid-gap: 0px;
    grid-template-areas: ". . . ." ". . . ." ". . . ." ". . . ." ". . equal equal";
    border-radius: 0px 0px 6px 6px;
}


.button {
    border:0.5px solid rgba(0, 0, 0, .07);
    text-align: center;
    background-color: rgba(0, 0, 0, 0);
}

#equal {
    background-color: rgba(0, 237, 255, 0.8);
    border-radius: 0px 0px 5px 0px;
    grid-area: equal;
}

.button:hover{
    background-color: rgba(255, 255, 255, 0.28);
    box-shadow: 0px 0px 10px -1px rgba(0,0,0,0.75);
    cursor: pointer ;
}

.equal:hover{
    background-color: hsl(184, 100%, 60%);
    box-shadow: 0px 0px 10px -1px rgba(0,0,0,0.75);
}

.button:active{
    background-color: rgba(255, 255, 255, 0.7);
    box-shadow: 0px 0px 18px -1px rgba(0,0,0,0.75);
}

.lighter{
    background-color: rgba(255, 255, 255, 0.28);
}

#nums{
    float: right;
    padding-right: 20px;
    padding-top: 15%;
    height: 40px;
    scale: 1.8;
    overflow: hidden;
}

h2{
    font-weight: 400;
    font-size: 30px;
    scale: 1.2;
    margin-top: 20px;
}