stil.css

body {
    font-family: 'Helvetica', sans-serif;
    background-color: #f4f4f4;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}

.calculator {
    width: 300px;
    height: 500px;
    background-color: #333;
    border-radius: 30px;
    padding: 20px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.display {
    width: 100%;
    height: 80px;
    background-color: #222;
    border-radius: 15px;
    margin-bottom: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.display input {
    width: 90%;
    height: 50px;
    background-color: transparent;
    border: none;
    color: white;
    font-size: 2em;
    text-align: right;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-gap: 10px;
}

button {
    width: 100%;
    height: 60px;
    font-size: 1.5em;
    background-color: #999;
    color: white;
    border: none;
    border-radius: 15px;
    cursor: pointer;
    transition: all 0.2s;
}

button:active {
    background-color: #666;
}

.operator {
    background-color: #fe9500;
}

button.zero {
    grid-column: span 2;
}

button:hover {
    opacity: 0.8;
}