style.css

*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Franklin Gothic Medium', 'Arial Narrow', Arial, sans-serif;
    letter-spacing: 1px;
}
body{
    min-height: 100vh;
    min-width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background:linear-gradient(45deg,black ,rgb(3, 102, 102));
}
.Calculator{
    padding: 15px;
    border: 2px solid rgb(116, 114, 114);
    box-shadow: 0 0 15px #000 ;
    border-radius: 15px;
}
.display input{
    width: 240px;
    border: none;
    outline: none;
    padding: 12px;
    margin: 8px;
    background: transparent;
    color: white;
    font-size: 27px;
    text-align: right;
    cursor: pointer;

}

input::placeholder{
    color: white;
}
button{
    width: 40px;
    height: 40px;
    margin:10px;
    background: transparent;
    color: white;
    font-size: 15px;
    font-weight: 500px;
    border: 0;
    box-shadow: -2px -2px 5px rgb(0, 0, 0);
    border-radius: 50%;
    outline: 1px solid #143b31;
    outline-offset: 2px;
    cursor: pointer;
}
button:active{
background-color: #000;
transform: translate(2px,2px);
}
.operator{
    color: #d6a77b;
    background: rgb(8, 40, 40);
    font-weight: 700px;
}
#equalbtn{
    background: rgba(0, 187, 165, 0.622);
    font-weight: 900px;
}