.tool-calculator {
    background: var(--background-color);
}

.tool-calculator .calculator-wrapper {
    border: none;
    border-radius: 1rem;
    background: #ffffff;
}

.calculator-header h1 {
    color: var(--primary-color);
}

.calculator-display {
    background: #111827;
    color: #f9fafb;
    border-radius: 0.75rem;
    padding: 0.75rem 1rem;
    min-height: 72px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    margin-bottom: 1rem;
}

.calculator-expression {
    font-size: 0.9rem;
    opacity: 0.75;
    min-height: 1.1rem;
    word-wrap: break-word;
}

.calculator-result {
    font-size: 1.8rem;
    font-weight: 600;
    text-align: right;
    word-wrap: break-word;
}

.calculator-keyboard {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.calculator-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.5rem;
}

.calculator-button {
    border: none;
    border-radius: 0.75rem;
    padding: 0.7rem 0;
    background: #e5e7eb;
    color: #111827;
    font-size: 1.05rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s ease, transform 0.05s ease, box-shadow 0.15s ease;
    box-shadow: 0 1px 2px rgba(15,23,42,0.08);
}

.calculator-button:active {
    transform: translateY(1px);
    box-shadow: 0 0 0 rgba(0,0,0,0);
}

.calculator-button-secondary {
    background: #e5e7eb;
    color: #374151;
}

.calculator-button-accent {
    background: var(--secondary-color);
    color: #ffffff;
}

.calculator-button-equal {
    background: var(--accent-color);
    color: #ffffff;
}

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

@media (max-width: 576px) {
    .calculator-wrapper {
        border-radius: 0.75rem;
    }

    .calculator-display {
        min-height: 64px;
    }

    .calculator-button {
        padding: 0.6rem 0;
        font-size: 1rem;
    }
}