.calculator {
    width: 320px;
    background: rgba(30, 30, 40, 0.8);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    padding: 25px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.1);
    margin: 20px 0;
}

.display {
    background: rgba(0, 0, 0, 0.2);
    border-radius: 10px;
    padding: 20px;
    margin-bottom: 20px;
    text-align: right;
    color: white;
    height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    position: relative;
    overflow: hidden;
}

.display::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(92, 108, 255, 0.5), transparent);
}

.previous-operand {
    font-size: 1.2rem;
    opacity: 0.7;
    min-height: 24px;
    word-break: break-all;
}

.current-operand {
    font-size: 2.5rem;
    font-weight: 500;
    word-break: break-all;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-gap: 12px;
}

button {
    border: none;
    border-radius: 12px;
    height: 60px;
    font-size: 1.3rem;
    font-weight: 500;
    cursor: pointer;
    background: rgba(255, 255, 255, 0.05);
    color: white;
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
}

button::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, rgba(255,255,255,0.2) 0%, transparent 70%);
    opacity: 0;
    transition: opacity 0.3s;
}

button:hover::before {
    opacity: 1;
}

button:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

button:active {
    transform: translateY(0);
    box-shadow: none;
}

button[data-operation] {
    background: rgba(92, 108, 255, 0.3);
}

button[data-operation]:hover {
    background: rgba(92, 108, 255, 0.4);
}

button[data-equals] {
    background: rgba(0, 212, 166, 0.3);
}

button[data-equals]:hover {
    background: rgba(0, 212, 166, 0.4);
}

button[data-all-clear] {
    background: rgba(255, 99, 71, 0.3);
}

button[data-all-clear]:hover {
    background: rgba(255, 99, 71, 0.4);
}

.span-two {
    grid-column: span 2;
}

@media (max-width: 400px) {
    .calculator {
        width: 280px;
        padding: 20px;
    }
    
    button {
        height: 55px;
        font-size: 1.2rem;
    }
    
    .current-operand {
        font-size: 2rem;
    }
}