*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: sans-serif;
    outline: none;
    border: none;
}
html,body{
    height: 100%;
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background: url(bgbg.jpg);
    background-size: 100%;
}
input{
    font-size: 25px;
    width: 600px;
    border: 1px solid gray;
    border-radius: 10px;
    padding: 25px 20px;
    text-align: right;
}
input::placeholder{
    padding: 25px 10px;
    color: gray;
    font-size: 25px;
}
button{
    font-size: 20px;
    border-radius: 5px;
    width: 100%;
    height: 100%;
    padding: 20px;
}
.not-num{
    color: white;
    background-color: rgb(124, 122, 122);
}
#equal{
    color: white;
    background-color: rgb(31, 31, 31);
}