/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-primary);
    line-height: 1.6;
    background-color: var(--bg-secondary);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header {
    background-color: var(--bg-primary);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 20px;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.2s;
}

.nav a:hover {
    color: var(--primary-color);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, #1d4ed8 100%);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.hero h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.hero .subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
}

/* Calculator Section */
.calculator-section {
    padding: 4rem 0;
}

.calculator-card {
    background: var(--bg-primary);
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
    padding: 3rem;
    max-width: 700px;
    margin: 0 auto;
}

.calculator-card h3 {
    font-size: 1.875rem;
    font-weight: 700;
    margin-bottom: 2rem;
    text-align: center;
}

/* Form Styles */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group small {
    display: block;
    margin-top: 0.25rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.checkbox-group label {
    display: flex;
    align-items: center;
    font-weight: 500;
    cursor: pointer;
}

.checkbox-group input[type="checkbox"] {
    width: auto;
    margin-right: 0.5rem;
    cursor: pointer;
}

/* Button */
.btn-primary {
    width: 100%;
    padding: 1rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.125rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

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

/* Results */
.results {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 2px solid var(--border-color);
}

.results.hidden {
    display: none;
}

.results-header h4 {
    font-size: 1.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
}

.refund-amount {
    text-align: center;
    font-size: 4rem;
    font-weight: 700;
    color: var(--success-color);
    margin: 1.5rem 0;
}

.refund-amount .currency {
    font-size: 3rem;
    opacity: 0.7;
}

.results-breakdown {
    background: var(--bg-tertiary);
    padding: 1.5rem;
    border-radius: 8px;
    margin: 2rem 0;
}

.results-breakdown h5 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

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

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

.breakdown-item.highlight {
    font-weight: 600;
    font-size: 1.125rem;
    color: var(--success-color);
    padding-top: 1rem;
    margin-top: 0.5rem;
    border-top: 2px solid var(--border-color);
}

.results-note {
    background: #fef3c7;
    border-left: 4px solid #f59e0b;
    padding: 1rem;
    border-radius: 4px;
    margin-top: 1.5rem;
}

.results-note p {
    color: #92400e;
    font-size: 0.875rem;
}

/* Info Section */
.info-section {
    padding: 4rem 0;
    background: var(--bg-primary);
}

.info-section h3 {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
}

.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.info-card {
    text-align: center;
    padding: 2rem;
    background: var(--bg-secondary);
    border-radius: 12px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.info-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.info-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.info-card h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}

.info-card p {
    color: var(--text-secondary);
}

/* FAQ Section */
.faq-section {
    padding: 4rem 0;
}

.faq-section h3 {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-primary);
    padding: 2rem;
    margin-bottom: 1.5rem;
    border-radius: 12px;
    box-shadow: var(--shadow-md);
}

.faq-item h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--primary-color);
}

.faq-item p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* Footer */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 3rem 0;
    text-align: center;
}

.footer p {
    margin-bottom: 0.5rem;
}

.disclaimer {
    font-size: 0.875rem;
    opacity: 0.7;
    max-width: 800px;
    margin: 1rem auto 0;
}

/* Responsive Design */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 1rem;
    }

    .nav {
        gap: 1rem;
    }

    .hero h2 {
        font-size: 2rem;
    }

    .hero .subtitle {
        font-size: 1.125rem;
    }

    .calculator-card {
        padding: 2rem 1.5rem;
    }

    .refund-amount {
        font-size: 3rem;
    }

    .refund-amount .currency {
        font-size: 2rem;
    }

    .info-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero h2 {
        font-size: 1.5rem;
    }

    .calculator-card {
        padding: 1.5rem 1rem;
    }

    .calculator-card h3 {
        font-size: 1.5rem;
    }
}