.calculator-container {
    display: flex;
    justify-content: center;
    padding: 2rem 0;
}

.calculator {
    background: white;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.15);
    padding: 2rem;
    width: 100%;
    max-width: 400px;
}

.calculator .display {
    background: #f8f9fa;
    border-radius: 12px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    text-align: right;
}

.calculator .history {
    color: #999;
    font-size: 0.9rem;
    min-height: 1.5rem;
    margin-bottom: 0.5rem;
}

.calculator .result {
    width: 100%;
    border: none;
    background: transparent;
    font-size: 2.5rem;
    font-weight: bold;
    text-align: right;
    color: #333;
    outline: none;
}

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

.calculator .btn {
    padding: 1.2rem;
    font-size: 1.3rem;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.2s;
    font-weight: 500;
}

.calculator .btn:hover {
    transform: translateY(-2px);
}

.calculator .btn:active {
    transform: translateY(0);
}

.calculator .btn-number {
    background: #f0f0f0;
    color: #333;
}

.calculator .btn-number:hover {
    background: #e0e0e0;
}

.calculator .btn-operator {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.calculator .btn-operator:hover {
    background: linear-gradient(135deg, #5a6fd6 0%, #6a4190 100%);
}

.calculator .btn-clear {
    background: #ff6b6b;
    color: white;
}

.calculator .btn-clear:hover {
    background: #ee5a5a;
}

.calculator .btn-equals {
    background: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
    color: white;
}