:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --success-color: #27ae60;
    --light-bg: #f8f9fa;
    --border-radius: 12px;
    --box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    --transition: all 0.3s ease;
}

body {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin-bottom: 3rem;
}

.header-card {
    background: linear-gradient(135deg, var(--primary-color) 0%, #34495e 100%);
    color: white;
    border-radius: var(--border-radius);
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--box-shadow);
    border: none;
}

.header-card h1 {
    font-weight: 700;
    margin-bottom: 0.5rem;
    font-size: 2.2rem;
}

.header-card .subtitle {
    opacity: 0.9;
    font-size: 1.1rem;
}

.warning-alert {
    background: #fff3cd;
    border: 2px solid #ffc107;
    border-radius: var(--border-radius);
    padding: 1rem 1.5rem;
    margin-bottom: 2rem;
    box-shadow: var(--box-shadow);
}

.warning-alert .alert-icon {
    color: var(--accent-color);
    font-size: 1.5rem;
    margin-right: 10px;
}

.calculator-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 2.5rem;
    box-shadow: var(--box-shadow);
    margin-bottom: 2rem;
    border: none;
}

.form-group {
    margin-bottom: 1.8rem;
}

.form-label {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.form-label i {
    color: var(--secondary-color);
    font-size: 1.1rem;
}

.form-control,
.form-select {
    border: 2px solid #e9ecef;
    border-radius: 8px;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus,
.form-select:focus {
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 0.25rem rgba(52, 152, 219, 0.25);
}

.form-text {
    font-size: 0.85rem;
    margin-top: 0.4rem;
    color: #6c757d;
}

.input-group-icon {
    position: relative;
}

.input-group-icon .form-control {
    padding-left: 2.5rem;
}

.input-group-icon i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: #6c757d;
    z-index: 10;
}

.btn-calculate {
    background: linear-gradient(135deg, var(--success-color) 0%, #2ecc71 100%);
    color: white;
    border: none;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 10px;
    box-shadow: 0 4px 15px rgba(39, 174, 96, 0.3);
}

.btn-calculate:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(39, 174, 96, 0.4);
}

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

.results-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 2.5rem;
    box-shadow: var(--box-shadow);
    animation: fadeIn 0.5s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.results-header {
    background: linear-gradient(135deg, var(--secondary-color) 0%, #2980b9 100%);
    color: white;
    padding: 1.5rem;
    border-radius: var(--border-radius) var(--border-radius) 0 0;
    margin: -1.5rem -1.5rem 2rem -1.5rem;
}

.total-cost {
    background: linear-gradient(135deg, var(--primary-color) 0%, #2c3e50 100%);
    color: white;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin: 1.5rem 0;
    text-align: center;
}

.total-cost h3 {
    font-size: 1.8rem;
    margin-bottom: 0.5rem;
}

.total-cost .amount {
    font-size: 2.5rem;
    font-weight: 700;
    margin: 0.5rem 0;
}

.total-cost .sub-amount {
    font-size: 1.2rem;
    opacity: 0.9;
}

.cost-breakdown {
    background: var(--light-bg);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-top: 1.5rem;
}

.cost-item {
    display: flex;
    justify-content: space-between;
    padding: 0.75rem 0;
    border-bottom: 1px solid #dee2e6;
    transition: var(--transition);
}

.cost-item:hover {
    background: rgba(255, 255, 255, 0.5);
}

.cost-item:last-child {
    border-bottom: none;
}

.cost-item .label {
    font-weight: 500;
    color: var(--primary-color);
}

.cost-item .value {
    font-weight: 600;
    color: var(--success-color);
}

.notes-box {
    background: #e8f4fc;
    border-left: 4px solid var(--secondary-color);
    padding: 1.5rem;
    border-radius: 0 var(--border-radius) var(--border-radius) 0;
    margin-top: 2rem;
}

.notes-box h5 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.notes-box ul {
    margin-bottom: 0;
}

.notes-box li {
    margin-bottom: 0.5rem;
    line-height: 1.5;
}

.info-box {
    background: #fff;
    border: 1px solid #e9ecef;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-top: 2rem;
    display: flex;
    align-items: flex-start;
    gap: 1rem;
}

.info-box i {
    color: var(--secondary-color);
    font-size: 1.5rem;
    flex-shrink: 0;
}

.highlight {
    color: var(--accent-color);
    font-weight: 600;
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    .calculator-card,
    .results-card {
        padding: 1.5rem;
    }

    .header-card h1 {
        font-size: 1.8rem;
    }

    .total-cost .amount {
        font-size: 2rem;
    }

    .btn-calculate {
        width: 100%;
        justify-content: center;
    }
}