body {
    background: #2d2d2d;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    font-family: monospace;
}

.calculator {
    background: #7b1e29;
    padding: 20px;
    border: 4px solid #3a0f12;
    box-shadow: 6px 6px 0px #1a0a0b;
    display: grid;
    grid-template-rows: auto 1fr;
    gap: 10px;
}

.display {
    background: #f46a5f;
    color: black;
    font-size: 24px;
    text-align: right;
    padding: 10px;
    border: 3px solid #3a0f12;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(4, 60px);
    gap: 8px;
}

button {
    background: #b35b6f;
    border: 3px solid #3a0f12;
    font-size: 20px;
    color: #000;
    padding: 10px;
    cursor: pointer;
    transition: 0.1s;
}

button:active {
    background: #8a4353;
    transform: translateY(2px);
}

.btn-equal {
    background: #ffb347;
}

.btn-clear {
    background: #5d3f4f;
    color: white;
}