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

body {
    font-family: 'Helvetica', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

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

/* Header Styles */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: #2563eb;
}

.logo-icon {
    margin-right: 0.5rem;
    font-size: 2rem;
}

.nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav a:hover {
    color: #2563eb;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 300;
}

.hero-subtitle {
    font-size: 1.2rem;
    margin-bottom: 3rem;
    opacity: 0.9;
}

/* Calculator Card */
.calculator-card {
    background: white;
    border-radius: 15px;
    padding: 2rem;
    max-width: 800px;
    margin: 0 auto;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    color: #333;
}

.calculator-controls {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.input-group {
    display: flex;
    flex-direction: column;
}

.input-group label {
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #555;
}

.date-input, .number-input, .select-input {
    padding: 0.75rem;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.date-input:focus, .number-input:focus, .select-input:focus {
    outline: none;
    border-color: #2563eb;
}

.calculate-btn {
    grid-column: 1 / -1;
    background: #2563eb;
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.calculate-btn:hover {
    background: #1d4ed8;
}

.result-display {
    background: #f8fafc;
    border-radius: 10px;
    padding: 1.5rem;
    text-align: center;
}

.result-display h3 {
    color: #374151;
    margin-bottom: 1rem;
}

.result-date {
    font-size: 2rem;
    font-weight: bold;
    color: #2563eb;
    margin-bottom: 0.5rem;
}

.result-details {
    color: #6b7280;
    font-size: 1rem;
}

/* Article Section */
.article-section {
    padding: 4rem 0;
    background: #fafafa;
}

.main-article {
    background: white;
    padding: 3rem;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    max-width: 900px;
    margin: 0 auto;
}

.main-article h2 {
    color: #1f2937;
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.main-article h3 {
    color: #374151;
    font-size: 1.8rem;
    margin: 2rem 0 1rem 0;
    border-bottom: 2px solid #e5e7eb;
    padding-bottom: 0.5rem;
}

.main-article h4 {
    color: #4b5563;
    font-size: 1.4rem;
    margin: 1.5rem 0 0.5rem 0;
}

.main-article p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.7;
}

.main-article strong {
    color: #2563eb;
    font-weight: 600;
}

/* Highlight Elements */
.highlight-quote {
    background: #f0f9ff;
    border-left: 4px solid #2563eb;
    padding: 1.5rem;
    margin: 2rem 0;
    font-style: italic;
    font-size: 1.2rem;
    border-radius: 0 8px 8px 0;
}

.highlight-box {
    background: linear-gradient(135deg, #fef3c7, #fcd34d);
    padding: 2rem;
    border-radius: 10px;
    margin: 2rem 0;
}

.highlight-box h4 {
    color: #92400e;
    margin-bottom: 1rem;
}

.highlight-box ul {
    list-style: none;
    padding-left: 0;
}

.highlight-box li {
    margin-bottom: 0.5rem;
    padding-left: 1.5rem;
    position: relative;
}

.highlight-box li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #059669;
    font-weight: bold;
}

/* Table Styles */
.info-table {
    width: 100%;
    border-collapse: collapse;
    margin: 2rem 0;
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.info-table th {
    background: #2563eb;
    color: white;
    padding: 1rem;
    text-align: left;
    font-weight: 600;
}

.info-table td {
    padding: 1rem;
    border-bottom: 1px solid #e5e7eb;
}

.info-table tr:nth-child(even) {
    background: #f9fafb;
}

/* Article Navigation */
.article-navigation {
    background: #f0f9ff;
    padding: 2rem;
    border-radius: 10px;
    margin: 3rem 0;
}

.article-navigation h4 {
    color: #1e40af;
    margin-bottom: 1rem;
}

.article-navigation ul {
    list-style: none;
}

.article-navigation li {
    margin-bottom: 0.5rem;
}

.article-navigation a {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
}

.article-navigation a:hover {
    text-decoration: underline;
}

/* Sources Section */
.sources-section {
    border-top: 2px solid #e5e7eb;
    padding-top: 2rem;
    margin-top: 3rem;
}

.sources-section h4 {
    color: #374151;
    margin-bottom: 1rem;
}

.sources-section ol {
    padding-left: 1.5rem;
}

.sources-section li {
    margin-bottom: 0.5rem;
    line-height: 1.5;
}

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    padding: 3rem 0 1rem 0;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    color: #f3f4f6;
}

.footer-section ul {
    list-style: none;
}

.footer-section li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: #60a5fa;
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: #2563eb;
    color: white;
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    display: none;
    transition: all 0.3s ease;
    z-index: 1000;
}

.back-to-top:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
}

.back-to-top.visible {
    display: block;
}

/* GDPR Banner */
.gdpr-banner {
    position: fixed;
    bottom: 20px;
    left: 20px;
    background: #1f2937;
    color: white;
    padding: 1rem;
    border-radius: 8px;
    max-width: 300px;
    z-index: 1001;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.gdpr-banner.hidden {
    display: none;
}

.gdpr-banner p {
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.gdpr-banner a {
    color: #60a5fa;
    text-decoration: none;
}

.gdpr-banner button {
    background: #2563eb;
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 1rem;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .calculator-controls {
        grid-template-columns: 1fr;
    }
    
    .main-article {
        padding: 2rem 1.5rem;
    }
    
    .main-article h2 {
        font-size: 2rem;
    }
    
    .main-article h3 {
        font-size: 1.5rem;
    }
    
    .info-table {
        font-size: 0.9rem;
    }
    
    .info-table th,
    .info-table td {
        padding: 0.75rem;
    }
    
    .gdpr-banner {
        left: 10px;
        right: 10px;
        max-width: none;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 2rem 0;
    }
    
    .calculator-card {
        padding: 1.5rem;
    }
    
    .main-article {
        padding: 1.5rem 1rem;
    }
}

/* Print Styles */
@media print {
    .header, .footer, .back-to-top, .gdpr-banner {
        display: none;
    }
    
    .main-article {
        box-shadow: none;
        padding: 0;
    }
    
    .hero {
        background: white;
        color: black;
        padding: 1rem 0;
    }
    
    .calculator-card {
        box-shadow: none;
        border: 1px solid #ccc;
    }
}