.calculator-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 70vh;
    padding: 20px;
}

.calculator {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 30px;
    border-radius: 20px;
    box-shadow: 0 20px 50px rgba(0,0,0,0.3);
    max-width: 400px;
    width: 100%;
}

.display {
    background: rgba(0,0,0,0.3);
    padding: 20px;
    border-radius: 10px;
    margin-bottom: 20px;
    min-height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    align-items: flex-end;
}

.history {
    color: rgba(255,255,255,0.6);
    font-size: 18px;
    min-height: 25px;
    margin-bottom: 5px;
}

.current {
    color: white;
    font-size: 40px;
    font-weight: bold;
    word-break: break-all;
}

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

.btn {
    padding: 20px;
    font-size: 24px;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.2s ease;
    font-weight: bold;
}

.btn:hover {
    transform: scale(1.05);
}

.btn:active {
    transform: scale(0.95);
}

.btn-number {
    background: rgba(255,255,255,0.9);
    color: var(--text-color);
}

.btn-number:hover {
    background: white;
}

.btn-operator {
    background: #ff9800;
    color: white;
}

.btn-operator:hover {
    background: #e68900;
}

.btn-equals {
    background: #4CAF50;
    color: white;
    grid-column: span 2;
}

.btn-equals:hover {
    background: #45a049;
}

.btn-clear, .btn-backspace, .btn-percent {
    background: #f44336;
    color: white;
}

.btn-clear:hover, .btn-backspace:hover, .btn-percent:hover {
    background: #da190b;
}

.btn-zero {
    grid-column: span 2;
    background: rgba(255,255,255,0.9);
    color: var(--text-color);
}

.btn-zero:hover {
    background: white;
}

.btn-decimal {
    background: rgba(255,255,255,0.9);
    color: var(--text-color);
}

.btn-decimal:hover {
    background: white;
}

@media (max-width: 480px) {
    .calculator {
        padding: 20px;
    }
    
    .btn {
        padding: 15px;
        font-size: 20px;
    }
    
    .current {
        font-size: 32px;
    }
}