.budget-calculator {
    max-width: 640px;
    margin: 2rem auto;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.budget-calculator__form {
    background: #fff;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 2.5rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.budget-calculator__section {
    margin-bottom: 2rem;
}

.budget-calculator__heading {
    font-size: 1.375rem;
    font-weight: 600;
    color: #1e293b;
    margin: 0 0 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #f1f5f9;
}

.budget-calculator__field {
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.budget-calculator__label {
    flex: 1;
    font-size: 1.125rem;
    color: #475569;
    font-weight: 500;
}

.budget-calculator__input {
    width: 180px;
    padding: 0.75rem 1rem;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    font-size: 1.125rem;
    color: #1e293b;
    background: #f8fafc;
    text-align: right;
    transition: border-color 0.2s, box-shadow 0.2s;
    box-sizing: border-box;
}

.budget-calculator__input:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
    background: #fff;
}

.budget-calculator__input::placeholder {
    color: #94a3b8;
}

.budget-calculator__input--income {
    width: 100%;
    font-size: 1.5rem;
    font-weight: 600;
    text-align: left;
    padding: 1rem 1.125rem;
}

.budget-calculator__result {
    background: #f0fdf4;
    border: 2px solid #86efac;
    border-radius: 12px;
    padding: 1.25rem 1.5rem;
    text-align: center;
}

.budget-calculator__result-label {
    font-size: 1.25rem;
    font-weight: 600;
    color: #166534;
    margin: 0 0 0.5rem;
}

.budget-calculator__result-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: #15803d;
    display: block;
}

.budget-calculator__result-value--negative {
    color: #dc2626;
}

.budget-calculator__result--negative {
    background: #fef2f2;
    border-color: #fca5a5;
}

.budget-calculator__result--negative .budget-calculator__result-label {
    color: #991b1b;
}

@media (max-width: 540px) {
    .budget-calculator__form {
        padding: 1.25rem;
    }

    .budget-calculator__field {
        flex-direction: column;
        align-items: stretch;
        gap: 0.25rem;
    }

    .budget-calculator__input {
        width: 100%;
        text-align: left;
    }
}