* {
    margin: 0; 
    padding: 0;
    box-sizing: border-box;
}

body {
    width: 100%;
    height: 100vh;
    background-color: lightgray;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

input {
    width: 90%;
    font-size: 2.5rem;
    font-weight: bold;
    border: none;
    border-radius: 6px;
    box-shadow: 0 0 15px gray ;

}

.main-container {
    margin-top: 2rem;
    border: none;
    width: 25rem;
    height: 25rem;
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    align-items: center;
    padding: 1rem;
    border-radius: 10px;
    box-shadow: inset 0 0 15px gray;
}

button {
    width: 5rem;
    height: 4rem;
    margin: 3px;
    border: none;
    border-radius: 10px;
    box-shadow: inset 0 0 20px gray;
    font-size: 30px;
    font-weight: bold;

}