style.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Roboto', sans-serif;
    font-size: 10px;
    background-color: #E5E1EE;
}

.container {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #E5E1EE;
}

.szamologep {
    display: grid;
    grid-template-columns: repeat(4, 6.8rem);
    padding: 1.6rem;
    border: 1px solid rgba(0, 0, 0, 0.4);
    border-radius: 2.8rem;
    box-shadow: 6px 6px 13px #fff,
                6px 6px 13px rgba(0,0,0,0.6);
}

.display {
    grid-column: span 4;
    height: 6.8rem;
    width: 27.2rem;
    box-shadow: inset -2px -2px 13px #fff,
                inset 2px 2px 13px rgba(0,0,0,0.6);
    border: none;
    border-radius: 2rem;
    text-align: end;
    margin: 3rem 0;
    padding: 2rem;
    font-size: 3rem;
    color: rgb(75, 74, 74);
}

.button {
    border: none;
    box-shadow: inset 2px 2px 13px #fff,
                inset 2px 2px 13px rgba(0,0,0,0.6);
    border-radius: 50%;
    width: 5rem;
    height: 5rem;
    margin: 1rem;
    font-weight: bold;
    font-size: 2rem;
    text-align: center;
    padding: 1.3rem;
}

.button:hover {
    background-color:#bdb9c5;
    cursor: pointer;
}

.egyenlo {
    box-shadow: inset 2px 2px 13px #fff,
                inset 2px 2px 13px rgba(0,0,0,0.6);
    border-radius: 50%;
    width: 12rem;
    border-radius: 2rem;
    margin: 1rem;
    padding: 1.3rem;
    font-weight: bold;
    font-size: 2rem;
    text-align: center;
}

.egyenlo:hover {
    background-color:#bdb9c5;
    cursor: pointer;
}